Rosetta mission poster showing the deployment of the Philae lander to comet 67P/Churyumov-Gerasimenko.. Credit: ESA/ATG medialab (Rosetta/Philae); ESA/Rosetta/NavCam (comet)
In August of 2014, the ESA’s Rosetta mission made history when it rendezvoused with the Comet 67P/Churyumov–Gerasimenko. For the next two years, the probe flew alongside the comet and conducted detailed studies of it. And in November of 2014, Rosetta deployed its Philae probe onto the comet, which was the first time in history that a lander was deployed to the surface of a comet.
During the course of its mission, Rosetta revealed some truly remarkable things about this comet, including data on its composition, its gaseous halo, and how it interacts with solar wind. In addition, the probe also got a good look at the endless stream of dust grains that were poured from the comet’s surface ice as it approached the Sun. From the images Rosetta captured, which the ESA just released, it looked a lot like driving through a snowstorm!
The image below was taken two years ago (on January 21st, 2016), when Rosetta was at a distance of 79 km from the comet. At the time, Rosetta was moving closer following the comet reaching perihelion, which took place during the previous August. When the comet was at perihelion, it was closer to the Sun and at its most active, which necessitated that Rosetta move farther away for its own protection.
Image of the dust and particles the Rosetta mission was exposed to as it flew alongside Comet 67P/Churyumov–Gerasimenko. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
As you can see from the image, the environment around the comet was extremely chaotic, even though it was five months after the comet was at perihelion. The white streaks reveal the dust grains as they flew in front of Rosetta’s camera over the course of a 146 second exposure. For the science team directing Rosetta, flying the spacecraft through these dust storms was like trying to drive a car through a blizzard.
Those who have tried know just how dangerous this can be! On the one hand, visibility is terrible thanks to all the flurries. On the other, the only way to stay oriented is to keep your eyes pealed for any landmarks or signs. And all the while, there is the danger of losing control and colliding with something. In much the same way, passing through the comet’s dust storms was a serious danger to the spacecraft.
In addition to the danger of collisions, flying through these clouds was also hazardous for the spacecraft’s navigation system. Like many robotic spacecraft, Rosetta relies on star trackers to orient itself – where it recognizes patterns in the field of stars to orient itself with respect to the Sun and Earth. When flying closer to the comet, Rosetta’s star trackers would occasionally become confused by dust grains, causing the craft to temporarily enter safe mode.
Artist’s impression of the Rosetta probe signalling Earth. Credits: ESA-C.Carreau
This occurred on March 28th, 2015 and again on May 30th, 2016, when Rosetta was conducting flybys that brought it to a distance of 14 and 5 km from the comet’s surface, respectively. On both occasions, Rosetta’s navigation system suffered from pointing errors when it began tracking bright dust grains instead of stars. As a result, on these occasions, the mission team lost contact with the probe for 24 hours.
“We lost contact with the spacecraft on Saturday evening for nearly 24 hours. Preliminary analysis by our flight dynamics team suggests that the star trackers locked on to a false star – that is, they were confused by comet dust close to the comet, as has been experienced before in the mission.”
Despite posing a danger to Rosetta’s solar arrays and its navigation system, this dust is also of high scientific interest. During the spacecraft’s flybys, three of its instruments studied tens of thousands of grains, analyzing their composition, mass, momentum and velocity, and also creating 3D profiles of their structure. By studying these tiny grains, scientists were also able to learn more about the bulk composition of comets.
Another snapshot of Comet 67P/Churyumov–Gerasimenko’s dusty emissions, taken on Jan. 21st, 2016. Credit: ESA
Before it reached its grand finale and crashed into the comet’s surface on September 30th, 2016, Rosetta made some unique scientific finds about the comet. These included mapping the comet’s surface features, discerning its overall shape, analyzing the chemical composition of its nucleus and coma, and measuring the ratio of water to heavy water on its surface.
All of these findings helped scientists to learn more about how our Solar System formed and evolved, and shed some light on how water was distributed throughout our Solar System early in its history. For instance, by determining that the ratio of water to heavy water on the comet was much different than that of Earth’s, scientists learned that Earth’s water was not likely to have come from comets like Comet 67P/Churyumov–Gerasimenko.
On top of that, the spacecraft took more than a hundred thousand image of the comet with its high-resolution OSIRIS camera (including the ones shown here) and its navigation camera. These images can be perused by going to the ESA’s image browser archive. I’m sure you’ll agree, they are all as beautiful as they are scientifically relevant!
The 18-segment gold coated primary mirror of NASA’s James Webb Space Telescope is raised into vertical alignment in the largest clean room at the agency’s Goddard Space Flight Center in Greenbelt, Maryland, on Nov. 2, 2016. The secondary mirror mount booms are folded down into stowed for launch configuration. Credit: Ken Kremer/kenkremer.com
The 18-segment gold coated primary mirror of NASA’s James Webb Space Telescope is raised into vertical alignment in the largest clean room at the agency’s Goddard Space Flight Center in Greenbelt, Maryland, on Nov. 2, 2016. The secondary mirror mount booms are folded down into stowed for launch configuration. Credit: Ken Kremer/kenkremer.com
The most powerful space telescope ever built will have to wait on the ground for a few more months into 2019 before launching to the High Frontier and looking back nearly to the beginning of time and unraveling untold astronomical secrets on how the early Universe evolved – Engineers need a bit more time to complete the Webb telescopes incredibly complex assembly and testing here on Earth.
“NASA’s James Webb Space Telescope now is planning to launch between March and June 2019 from French Guiana, following a schedule assessment of the remaining integration and test activities,” the agency announced.
Until now the Webb telescope was scheduled to launch on a European Space Agency (ESA) Ariane V booster from the Guiana Space Center in Kourou, French Guiana in October 2018.
“The change in launch timing is not indicative of hardware or technical performance concerns,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at Headquarters in Washington, in a statement.
“Rather, the integration of the various spacecraft elements is taking longer than expected.”
NASA’s says the currently approved budget will not bust the budget or reduce the science output. It “accommodates the change in launch date, and the change will not affect planned science observations.”
NASA’s $8.8 Billion James Webb Space Telescope is the most powerful space telescope ever built and is the scientific successor to the phenomenally successful Hubble Space Telescope (HST).
The Webb Telescope is a joint international collaborative project between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
Up close side-view of newly exposed gold coated primary mirrors installed onto mirror backplane holding structure of NASA’s James Webb Space Telescope inside the massive clean room at NASA’s Goddard Space Flight Center in Greenbelt, Maryland on May 3, 2016. Aft optics subsystem stands upright at center of 18 mirror segments between stowed secondary mirror mount booms. Credit: Ken Kremer/kenkremer.com
Since Webb is not designed to be serviced by astronauts, the extremely thorny telescope deployment process is designed to occur on its own over a period of several months and must be fully successful. Webb will be positioned at the L2 Lagrange point- a gravitationally stable spot approximately 930,000 miles (1.5 million km) away from Earth.
So its better to be safe than sorry and take the extra time needed to insure success of the hugely expensive project.
NASA’s James Webb Space Telescope sits in Chamber A at NASA’s Johnson Space Center in Houston awaiting the colossal door to close in July 2017 for cryogenic testing. Credits: NASA/Chris Gunn
Various completed components of the Webb telescope are undergoing final testing around the country to confirm their suitability for launch.
Critical cryogenic cooling testing of Webb’s mirrors and science instrument bus is proceeding well inside a giant chamber at NASA’s Johnson Space Center in Texas.
However integration and testing of the complex multilayered sunshield at Northrup Grumman’s Redondo Beach, Ca. facility is taking longer than expected and “has experienced delays.”
The tennis court sized sunshield will protect the delicate optics and state of the art infrared science instruments on NASA’s Webb Telescope.
Webb’s four research instruments cannot function without the essential cooling provided by the sunshield deployment to maintain them at an operating temperature of minus 388 degrees F (minus 233 degrees C).
The Webb telescopes groundbreaking sunshield subsystem consists of five layers of kapton that will keep the optics and instruments incredibly cool, by reducing the incoming sunside facing temperature more than 570 degrees Fahrenheit. Each layer is as thin as a human hair.
All 5 layers of the Webb telescope sunshield installed at Northrop Grumman’s clean room in Redondo Beach, California. The five sunshield membrane layers are each as thin as a human hair. Credits: Northrop Grumman Corp.
“Webb’s spacecraft and sunshield are larger and more complex than most spacecraft. The combination of some integration activities taking longer than initially planned, such as the installation of more than 100 sunshield membrane release devices, factoring in lessons learned from earlier testing, like longer time spans for vibration testing, has meant the integration and testing process is just taking longer,” said Eric Smith, program director for the James Webb Space Telescope at NASA Headquarters in Washington, in a statement.
“Considering the investment NASA has made, and the good performance to date, we want to proceed very systematically through these tests to be ready for a Spring 2019 launch.”
Artist’s concept of the James Webb Space Telescope (JWST) with Sunshield at bottom. Credit: NASA/ESA
Northrop Grumman designed the Webb telescope’s optics and spacecraft bus for NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which manages Webb.
Watch for Ken’s onsite space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Learn more about the upcoming ULA Atlas NRO NROL-52 spysat launch on Oct 5 and SpaceX Falcon 9 SES-11 launch on Oct 7, JWST, OSIRIS-REx, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:
Oct 3-6, 8: “ULA Atlas NRO NROL-52 spysat launch, SpaceX SES-11, CRS-12 resupply launches to the ISS, Intelsat35e, BulgariaSat 1 and NRO Spysat, SLS, Orion, Commercial crew capsules from Boeing and SpaceX , Heroes and Legends at KSCVC, ULA Atlas/John Glenn Cygnus launch to ISS, SBIRS GEO 3 launch, GOES-R weather satellite launch, OSIRIS-Rex, Juno at Jupiter, InSight Mars lander, SpaceX and Orbital ATK cargo missions to the ISS, ULA Delta 4 Heavy spy satellite, Curiosity and Opportunity explore Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Mars Express' view of Meridiani Planum. Credits: ESA/DLR/FU Berlin (G. Neukum)
It is a well-known fact that today, Mars is a very cold and dry place. Whereas the planet once had a thicker atmosphere that allowed for warmer temperatures and liquid water on its surface, the vast majority of water there today consists of ice that is located in the polar regions. But for some time, scientists have speculated that there may be plenty of water in subsurface ice deposits.
If true, this water could be accessed by future crewed missions and even colonization efforts, serving as a source of rocket fuel and drinking water. Unfortunately, a new study led by scientists from the Smithsonian Institution indicates that the subsurface region beneath Meridiani Planum could be ice-free. Though this may seem like bad news, the study could help point the way towards accessible areas of water ice on Mars.
Artist’s impression of a global view of Mars, centered on the Meridiani Planum region. Credit: Air and Space Museum/Smithsonian Institution
Despite being one of the most intensely explored regions on Mars, particularly by missions like the Opportunity rover, the subsurface structure of Meridiani Planum has remained largely unknown. To remedy this, the science team led by Dr. Watters examined data that had been collected by the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument aboard the ESA’s Mars Express orbiter.
Developed by researchers at the University of Rome in partnership with NASA’s Jet Propulsion Laboratory (and with the help of private contractors), this device used low-frequency radio pulses to study Mars’ ionosphere, atmosphere, surface, and interior structure. The way these pulses penetrated into certain materials and were reflected back to the orbiter was then used to determine the bulk density and compositions of those materials.
After examining the Meridiani Planum region, the Mars Express probe obtained readings that indicated that the subsurface area had a relatively low dielectric constant. In the past, these kinds of readings have been interpreted as being due to the presence of pure water ice. And in this case, the readings seemed to indicate that the subsurface was made up of porous rock that was filled with water ice.
However, with the help of newly-derived compaction models for Mars, the team concluded that these signals could be the result of ice-free, porous, windblown sand (aka. eolian sands). They further theorized that the Meridiani Planum region, which is characterized by some rather unique physiographic and hydrologic features, could have provided an ideal sediment trap for these kinds of sands.
Artist’s impression of the Mars Express rover, showing radar returns from its MARSIS instrument. Credit: ESA/NASA/JPL/KU/Smithsonian
“The relatively low gravity and the cold, dry climate that has dominated Mars for billions of years may have allowed thick eolian sand deposits to remain porous and only weakly indurated,” they concluded. “Minimally compacted sedimentary deposits may offer a possible explanation for other nonpolar region units with low apparent bulk dielectric constants.”
“It’s very revealing that the low dielectric constant of the Meridiani Planum deposits can be explained without invoking pore-filling ice. Our results suggest that caution should be exercised in attributing non-polar deposits on Mars with low dielectric constants to the presence of water ice.”
On its face, this would seem like bad news to those who were hoping that the equatorial regions on Mars might contain vast deposits of accessible water ice. It has been argued that when crewed missions to Mars begin, this ice could be accessed in order to supply water for surface habitats. In addition, ice that didn’t need to come from there could also be used to manufacture hydrazine fuel for return missions.
This would reduce travel times and the cost of mounting missions to Mars considerably since the spacecraft would not need to carry enough fuel for the entire journey, and would therefore be smaller and faster. In the event that human beings establish a colony on Mars someday, these same subsurface deposits could also used for drinking, sanitation, and irrigation water.
A subsurface view of Miyamoto crater in Meridiani Planum from the MARSIS radar sounder. . Credit: ESA/NASA/JPL/KU/Smithsonian
As such, this study – which indicates that low dielectric constants could be due to something other than the presence of water ice – places a bit of a damper on these plans. However, understood in context, it provides scientists with a means of locating subsurface ice. Rather than ruling out the presence of subsurface ice away from the polar regions entirely, it could actually help point the way to much-needed deposits.
One can only hope that these regions are not confined to the polar regions of the planet, which would be far more difficult to access. If future missions and (fingers crossed!) permanent outposts are forced to pump in their water, it would be far more economical to do from underground sources, rather than bringing it in all the way from the polar ice caps.
A computer generated handout image released by the European Space Agency shows the impact of the DART (Double Asteroid Redirection Test) projectile on the binary asteroid system (65803) Didymos. Credit: ESA/AFP
For decades, scientists have known that in near-Earth space there are thousands of comets and asteroids that periodically cross Earth’s orbit. These Near-Earth Objects (NEOs) are routinely tracked by NASA’s Center for Near Earth Object Studies (CNEOS) to make sure that none pose a risk of collision with our planet. Various programs and missions have also been proposed to divert or destroy any asteroids that might pass too closely to Earth in the future.
One such mission is the Asteroid Impact & Deflection Assessment (AIDA), a collaborative effort between NASA and the European Space Agency (ESA). Recently, the ESA announced that it would be withdrawing from this mission due to budget constraints. But this past Wednesday (Sept. 20th), during the European Planetary Science Conference in Riga, a group of international scientists urged them to reconsider.
In addition to NASA and the ESA, AIDA was designed with assistance from the Observatoire de la Côte d´Azur (OCA), and the Johns Hopkins University Applied Physics Laboratory (JHUAPL). To test possible asteroid deflection techniques, the mission intends to send a spacecraft to crash into the tiny moon of the distant asteroid named Didymos (nicknamed “Didymoon”) by 2022 to alter its trajectory.
Artist’s impression of the path DART will take to reach the asteroid Didymos. Credit: NASA
This mission would be a first for scientists, and would test the capabilities of space agencies to divert rocks away from Earth’s orbit. NASA’s contribution to this mission is known as the Double Asteroid Redirection Test (DART), the spacecraft which would be responsible for crashing into Didymoon. Plans for this spacecraft recently entered Phase B, having met with approval, but still in need of further development.
The plan was to mount DART on an already planned commercial or military launch, and would then be placed in geosynchronous orbit between December 2020 and May 2021. It would then rely on a NEXT-C ion engine to push itself beyond the Moon and reach an escape point to depart the Earth-Moon system, eventually making its way to Didymos and Didymoon.
Europe’s contribution to the mission was known as the Asteroid Impact Mission (AIM), which would involve sending a small craft close to Didymos to observe the crash and conduct research on the asteroid’s moon. Unfortunately, this aspect of the mission suffered a setback when space ministers from the ESA’s 22 member states rejected a €250 million ($300 million USD) request for funding last December.
However, during the European Planetary Science Congress – which will be taking place from September 17th to 22nd in the Latvian capital of Riga – scientists took the opportunity to advise the mission’s European partners to get back on board. As they emphasized, this mission – which is a dry-run for future asteroid redirect missions – is crucial if space agencies hope to develop the capacity to protect Earth from hazardous NEOs.
ESA’s Asteroid Impact Mission, a candidate mission due for launch in 2020, will map the smaller body of the Didymos binary asteroid system down to 1 m resolution following its arrival in 2022. Credit: ESA
Andrew Cheng from JHUAPL is the project scientist for the DART mission. As he told the AFP at the European Planetary Science Congress, “This is the kind of disaster that could be a tremendous catastrophe.” He also stressed that unlike other natural disasters, an asteroid strike “is something that the world is able to defend. We can do something.”
But before that can happen, the methods need to be further developed, tested and refined. Hence why Didymoon was selected as the target for the AIDA mission. Whereas the meteor that exploded over the Russian town of Chelyabinsk in 2013 was just 20 meters across (65 feet), but still injured 1600 people, Didymoon measures about 160 meters (525 feet) in diameter.
It is estimated that if this asteroid struck Earth, the resulting impact would be as powerful as a 400 megatonne blast. To put that in perspective, the most powerful thermonuclear device ever built – the Soviet Tsar Bomba – had a yield of 50 megatonnes. Hence, the smaller companion of this binary asteroid, if it struck Earth, would have an impact 80 times greater than the most powerful bomb ever built by humans.
In addition to advocating that the ESA remain committed to the mission, European scientists at the conference also proposed an altered, more cost-effective alternative for AIM. This alternative called for a miniaturized version of the AIM craft that would be equipped with just a camera, forgoing a lander and radars designed to probe Didymoon’s internal structure.
Simulated image of the Didymos system, derived from photometric lightcurve and radar data. Credits: Naidu et al./AIDA Workshop (2016)
According to Patrick Michel, the science lead for the AIM mission, this revised mission would cost about €210 million ($250 million USD). But as he also noted, this would require that the AIM part of the mission be delayed. While it would still conduct crucial measurements of Didymoon, it would not be part of the AIDA mission if NASA decides to stick with its original timeline.
“The main point of the mission was to measure the mass of the object, because this is how you really measure the deflection,” he said. “Two or three years (after impact), these things won’t change. Of course it’s better… that we have the two at the same time. But we found something I think that still works and allows to relax the very tight schedule.”
In the meantime, Jan Woerner – the head of the European Space Agency – indicated that the ESA would be moving forward with the new proposal when the next ministerial meeting takes place in 2019. As he told the AFP via email:
“It is important for humanity, as a species we have the means today to deflect an asteroid. We know it will happen, one day sooner or later. It’s not a question of if, but when. We have never tested asteroid deflection and there is no way we can test in (the) laboratory. We need to know if our models are correct, (whether) our simulations work as expected.”
In the end, it remains to be seen if the AIDA mission will see one or two missions traveling to Didymoon by 2022. Obviously, it would be better if both mission happened simultaneously, as the AIM mission will be capable of obtaining information DART will not. Much of that information has to do with with studying the effects of the collision up close and as they happen.
But regardless of how this mission unfolds, it is clear that space agencies from around the world are dedicated to developing techniques for protecting Earth from asteroids that pose a collision hazard. Between NASA, the ESA, and their many institutional partners and private contractors, multiple methods are being developed to divert or destroy oncoming space rocks before they hit us.
However, I’m pretty sure not one of them involves sending a bunch of miners with minimal training into space to plant a nuke inside an asteroid. That would just be silly on its face!
And be sure to check out this video that details the AIDA and Asteroid Impact Mission, courtesy of ESA:
Artist's impression of the Venus Express spacecraft in orbit around Venus. Credit: ESA
Venus’ atmosphere is as mysterious as it is dense and scorching. For generations, scientists have sought to study it using ground-based telescopes, orbital missions, and the occasional atmospheric probe. And in 2006, the ESA’s Venus Express mission became the first probe to conduct long-term observations of the planet’s atmosphere, which revealed much about its dynamics.
Using this data, a team of international scientists – led by researchers from the Japan Aerospace and Exploration Agency (JAXA) – recently conducted a study that characterized the wind and upper cloud patterns on the night side of Venus. In addition to being the first of its kind, this study also revealed that the atmosphere behaves differently on the night side, which was unexpected.
The study, titled “Stationary Waves and Slowly Moving Features in the Night Upper Clouds of Venus“, recently appeared in the scientific journal Nature Astronomy. Led by Javier Peralta, the International Top Young Fellow of JAXA, the team consulted data obtained by Venus Express’ suite of scientific instruments in order to study the planet’s previously-unseen cloud types, morphologies, and dynamics.
The atmospheric super-rotation at the upper clouds of Venus. While the super-rotation is present in both day and night sides of Venus, it seems more uniform in the day. Credits: JAXA, ESA, J. Peralta and R. Hueso.
Whereas plenty of studies have been conducted of Venus’ atmosphere from soace, this was the first time that a study was not focused on the dayside of the planet. As Dr. Peralta explained in an ESA press statement:
“This is the first time we’ve been able to characterize how the atmosphere circulates on the night side of Venus on a global scale. While the atmospheric circulation on the planet’s dayside has been extensively explored, there was still much to discover about the night side. We found that the cloud patterns there are different to those on the dayside, and influenced by Venus’ topography.“
Since the 1960s, astronomers have been aware that Venus’ atmosphere behaves much differently that those of other terrestrial planets. Whereas Earth and Mars have atmospheres that co-rotate at approximately the same speed as the planet, Venus’ atmosphere can reach speeds of more than 360 km/h (224 mph). So while the planet takes 243 days to rotate once on its axis, the atmosphere takes only 4 days.
This phenomena, known as “super-rotation”, essentially means that the atmosphere moves over 60 times faster than the planet itself. In addition, measurements in the past have shown that the fastest clouds are located at the upper cloud level, 65 to 72 km (40 to 45 mi) above the surface. Despite decades of study, atmospheric models have been unable to reproduce super-rotation, which indicated that some of the mechanics were unknown.
As such, Peralta and his international team – which included researchers from the Universidad del País Vasco in Spain, the University of Tokyo, the Kyoto Sangyo University, the Center for Astronomy and Astrophysics (ZAA) at Berlin Technical University, and the Institute of Astrophysics and Space Planetology in Rome – chose to look at the unexplored side to see what they could find. As he described it:
“We focused on the night side because it had been poorly explored; we can see the upper clouds on the planet’s night side via their thermal emission, but it’s been difficult to observe them properly because the contrast in our infrared images was too low to pick up enough detail.”
This consisted of observing Venus’ night side clouds with the probe’s Visible and Infrared Thermal Imaging Spectrometer (VIRTIS). The instrument gathered hundreds of images simultaneously and different wavelengths, which the team then combined to improve the visibility of the clouds. This allowed the team to see them properly for the first time, and also revealed some unexpected things about Venus’ night side atmosphere.
What they saw was that atmospheric rotation appeared to be more chaotic on the night side than what has been observed in the past on the dayside. The upper clouds also formed different shapes and morphologies – i.e. large, wavy, patchy, irregular and filament-like patterns – and were dominated by stationary waves, where two waves moving in opposite directions cancel each other out and create a static weather pattern.
Examples of new types of cloud morphology discovered on the night side of Venus thanks to Venus Express (ESA) and the infrared telescope IRTF (NASA). Credits: ESA/NASA/J. Peralta and R. Hueso.
The 3D properties of these stationary waves were also obtained by combining VIRTIS data with radio-science data from the Venus Radio Science experiment (VeRa). Naturally, the team was surprised to find these kinds of atmospheric behaviors since they were inconsistent with what has been routinely observed on the dayside. Moreover, they contradict the best models for explaining the dynamics of Venus’ atmosphere.
Known as Global Circulation Models (GCMs), these models predict that on Venus, super-rotation would occur in much the same way on both the dayside and the night side. What’s more, they noticed that stationary waves on the night side appeared to coincide with high-elevation features. As Agustin Sánchez-Lavega, a researcher from the University del País Vasco and a co-author on the paper, explained:
“Stationary waves are probably what we’d call gravity waves–in other words, rising waves generated lower in Venus’ atmosphere that appear not to move with the planet’s rotation. These waves are concentrated over steep, mountainous areas of Venus; this suggests that the planet’s topography is affecting what happens way up above in the clouds.“
This is not the first time that scientists have spotted a possible link between Venus’ topography and its atmospheric motion. Last year, a team of European astronomers produced a study that showed how weather patterns and rising waves on the dayside appeared to be directly connected to topographical features. These findings were based on UV images taken by the Venus Monitoring Camera (VMC) on board the Venus Express.
Schematic illustration of the proposed behaviour of gravity waves in the vicinity of mountainous terrain on Venus. Credit: ESA
Finding something similar happening on the night side was something of a surprise, until they realized they weren’t the only ones to spot them. As Peralta indicated:
“It was an exciting moment when we realized that some of the cloud features in the VIRTIS images didn’t move along with the atmosphere. We had a long debate about whether the results were real–until we realised that another team, led by co-author Dr. Kouyama, had also independently discovered stationary clouds on the night side using NASA’s Infrared Telescope Facility (IRTF) in Hawaii! Our findings were confirmed when JAXA’s Akatsuki spacecraft was inserted into orbit around Venus and immediately spotted the biggest stationary wave ever observed in the Solar System on Venus’ dayside.“
These findings also challenge existing models of stationary waves, which are expected to form from the interaction of surface wind and high-elevation surface features. However, previous measurements conducted by the Soviet-era Venera landers have indicated that surface winds might too weak for this to happen on Venus. In addition, the southern hemisphere, which the team observed for their study, is quite low in elevation.
And as Ricardo Hueso of the University of the Basque Country (and a co-author on the paper) indicated, they did not detect corresponding stationary waves in the lower cloud levels. “We expected to find these waves in the lower levels because we see them in the upper levels, and we thought that they rose up through the cloud from the surface,” he said. “It’s an unexpected result for sure, and we’ll all need to revisit our models of Venus to explore its meaning.”
Artist’s impression of Venus Express performing aerobreaking maneuvers in the planet’s atmosphere in June and July 2014. Credit: ESA–C. Carreau
From this information, it seems that topography and elevation are linked when it comes to Venus’ atmospheric behavior, but not consistently. So the standing waves observed on Venus’ night side may be the result of some other undetected mechanism at work. Alas, it seems that Venus’ atmosphere – in particular, the key aspect of super-rotation – still has some mysteries for us.
The study also demonstrated the effectiveness of combining data from multiple sources to get a more detailed picture of a planet’s dynamics. With further improvements in instrumentation and data-sharing (and perhaps another mission or two to the surface) we can expect to get a clearer picture of what is powering Venus’ atmospheric dynamics before long.
With a little luck, there may yet come a day when we can model the atmosphere of Venus and predict its weather patterns as accurately as we do those of Earth.
The Soyuz MS-04 vehicle is pictured the moment it touches down with the Expedition 52 crew inside comprising NASA astronauts Peggy Whitson and Jack Fisher and Commander Fyodor Yurchikhin of Roscosmos on Sept. 3, 2017, Kazakhstan time. Credit: NASA/Bill Ingalls
The Soyuz MS-04 vehicle is pictured the moment it touches down with the Expedition 52 crew inside comprising NASA astronauts Peggy Whitson and Jack Fisher and Commander Fyodor Yurchikhin of Roscosmos on Sept. 3, 2017, Kazakhstan time. Credit: NASA/Bill Ingalls
NASA’s Peggy Whitson, America’s most experienced astronaut, returned to Earth safely and smiling Sunday morning on the steppes of Kazakhstan, concluding her record-breaking stay in space aboard the International Space Station (ISS) along with Soyuz crewmates Jack Fischer of NASA and Commander Fyodor Yurchikhin of Roscosmos.
The multinational trio touched down softly on Earth inside their Soyuz MS-04 descent capsule on Saturday evening, Sept. 2 at 9:21 p.m. EDT (shortly after sunrise 7:21 a.m. Kazakhstan time, Sept. 3), some 90 miles southeast of the remote town of Dzhezkazgan in Kazakhstan.
Whitson wrapped up a 288-day extended mission in obviously good health that began in November 2016, spanning 122.2 million miles and 4,623 orbits of Earth – completing her third long-duration stay on the orbiting science outpost spanning Expeditions 50, 51 and 52.
“A flawless descent and landing,” said NASA commentator Rob Navias during the live NASA TV coverage of the return of the ISS Expedition 52 crew Saturday afternoon and evening US time.
“The crew is back on Earth safe and sound.”
NASA astronaut Peggy Whitson, Russian cosmonaut Fyodor Yurchikhin of Roscosmos, and NASA astronaut Jack Fischer undergo routine initial medical checks after returning from their mission aboard the International Space Station at 9:21 p.m. EDT Saturday, Sept. 2, 2017 (7:21 a.m. Kazakhstan time, Sunday, Sept. 3), landing southeast of the remote town of Dzhezkazgan in Kazakhstan. Credits: NASA TV
She has now accrued a total of 665 days in space – more than any American astronaut – over the course of her illustrious career during which she set multiple U.S. space records spanning a total of three spaceflights.
Whitson’s 665 total accumulated days in space places her eighth on the all-time space endurance list – just 8 days behind her Russian crewmate and Soyuz Commander Fyodor Yurchikhin who now ranks 7th on the all-time list with 673 days in space on his five flights. She has exceeded the endurance record of her next closest NASA competitor by 131 days – namely NASA astronaut Jeff Williams.
The remarkable 57-year-old Ph.D biochemist by training has spent nearly 2 years of her entire life in space and she holds several other prestigious records as well – including more accumulated time in space than any other woman and the longest single spaceflight by a women – 288 days!
During this mission Whitson became the first woman to serve twice as space station commander. Indeed in 2008 Whitson became the first woman ever to command the space station during her prior stay on Expedition 16 a decade ago. Her second stint as station commander this mission began earlier this year on April 9.
Whitson also holds the record for the most spacewalks and the most time spent spacewalking by a female astronaut. Altogether she has accumulated 60 hours and 21 minutes of EVA time over ten spacewalks -ranking her third most experienced in the world.
Notably Soyuz Commander Yurchikhin ranks fourth in spacewalking experience. Only Russia’s Anatoly Solovyev and NASA’s Michael Lopez-Alegria have more spacewalking time to their credit.
NASA’s Jack Fischer completed his rookie spaceflight accumulating 136 days in space aboard the ISS.
Astronaut Peggy Whitson is pictured May 12, 2017, during the 200th spacewalk at the International Space Station. Credit: NASA
Whitson originally launched to the ISS on Nov 17, 2016 aboard the Russian Soyuz MS-03 spacecraft from the Baikonur Cosmodrome in Kazakhstan, as part of the three person Expedition 50 crew including flight engineers Oleg Novitskiy of Roscosmos and Thomas Pesquet of ESA (European Space Agency).
Her flight was unexpectedly extended in flight after the Russian government decided to cut back on the number of space station crew cosmonauts this year from three to two to save money. Thus a return seat became available on this Soyuz MS-04 return flight after NASA negotiated an extension with Rosmoscos in April enabling Whitson to remain on board the orbiting outpost an additional three months beyond her than planned June return home.
Whitson’s mission extension proved to be a boon for NASA and science research enabling the US/partner USOS crew complement to be enlarged from three to four full time astronauts much earlier than expected. This allowed NASA to about double the weekly time devoted to research aboard station – a feat not expected to happen until America’s commercial crew vehicles, namely Boeing Starliner and SpaceX Crew Dragon – finally begin inaugural launches next year from the Kennedy Space Center in mid-2018.
NASA Astronaut Peggy Whitson after safe return to Earth on Sept. 2, 2017 ET. Credit: NASA
Descending dramatically while hanging below a single gigantic orange-and-white parachute the scorched Russian Soyuz vehicle fired its braking rockets just moments before touchdown in Kazakhstan to cushion the crew for a gentle landing under beautifully sunny skies.
A live NASA TV video feed captured the thrilling descent for over 14 minutes after the main parachute deployed all the way to the ground under clear blue sunny Sunday morning weather conditions and comfortably local Kazakh temperatures of 77 degrees F.
“Everything today went in perfect fashion from the undocking, to the deorbit burn to landing,” said Navias. “It went by the book with no issues.”
“We saw a spectacular 14 minute long live video of the Soyuz descent and landing.”
The Soyuz MS-04 carrying NASA astronauts Peggy Whitson and Jack Fischer and Fyodor Yurchikin of Roscosmos back to Earth from the International Space Station touched down at at 9:21 p.m. EDT Saturday, Sept. 2 (7:21 a.m. Kazakhstan time, Sunday, Sept. 3), southeast of the remote town of Dzhezkazgan in Kazakhstan. Credits: NASA TV
Russian search and recovery forces quickly arrived via a cluster of MI-8 helicopters after the soft landing to begin their normal procedures to extract the three Expedition 52 crew members from their cramped Soyuz descent module.
Soyuz Commander Yurchikhin in the center seat was hauled out first, followed by Fischer in the left side seat and lastly Whitson in the right seat. All 3 were placed on reclining seats sitting side by side and appeared quite well, conversing and speaking via satellite phones.
A group of Russian and US medical teams were on hand to check the astronauts and cosmonauts health and help the crewmates begin readapting to the tug of Earth’s gravity they have not experienced after many months of weightlessness in space.
Whitson’s final planned news conference from space with the media to sum up her experiences this past Wednesday had to be cancelled due to the catastrophic flooding events from Hurricane Harvey impacting Houston and elsewhere in Texas – including Mission Control which was forced to close multiple days.
The crews had bid their final farewells earlier and closed the hatches between the Soyuz and station at 2:40 p.m. EDT Saturday.
After conducting final spacecraft systems checks the trio unhooked the latches and undocked from the International Space Station at 5:58 p.m. EDT to begin their voyage home through the scorching heats of reentry in the Earth’s atmosphere that reached over 2500 degrees F (1400 degrees C) on the outside.
“While living and working aboard the world’s only orbiting laboratory, Whitson and Fischer contributed to hundreds of experiments in biology, biotechnology, physical science and Earth science, welcomed several cargo spacecraft delivering tons of supplies and research experiments, and conducted a combined six spacewalks to perform maintenance and upgrades to the station,” said NASA.
“Among their scientific exploits, Whitson and Fischer supported research into the physical changes to astronaut’s eyes caused by prolonged exposure to a microgravity environment. They also conducted a new lung tissue study that explored how stem cells work in the unique microgravity environment of the space station, which may pave the way for future stem cell research in space.”
“Additional research included an antibody investigation that could increase the effectiveness of chemotherapy drugs for cancer treatment, and the study of plant physiology and growth in space using an advanced plant habitat. NASA also attached the Cosmic Ray Energetics and Mass Investigation (ISS CREAM) on the outside of the space station in August, which is now observing cosmic rays coming from across the galaxy.”
Astronaut Peggy Whitson signs her autograph near an Expedition 50 mission patch attached to the inside the International Space Station. Credit: NASA
ISS Expedition 53 began at the moment of undocking from the space station, now under the command of veteran NASA astronaut Randy Bresnik since the official change of command ceremony on Friday.
Along with his crewmates Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of ESA (European Space Agency), the three-person crew will operate the station for the next 10 days until the imminent arrival of three new crew members.
The station will get back to a full complement of six crewmembers after the upcoming Sept. 12 launch and fast track 4 orbit 6 hour docking of NASA astronauts Mark Vande Hei and Joe Acaba of NASA and Alexander Misurkin of Roscosmos aboard the next Soyuz MS-06 spacecraft departing from the Baikonur Cosmodrome, Kazakhstan.
Peggy Whitson set the record on Sept. 2, 2017, for most cumulative days living and working in space by a NASA astronaut at 665 days. Credit: NASAExpedition 52 Flight Engineer Peggy Whitson of NASA, Commander Fyodor Yurchikhin of the Russian space agency Roscosmos and Flight Engineer Jack Fischer of NASA float through the Harmony module of the International Space Station. Credits: NASA
Watch for Ken’s continuing onsite X-37B OTV-5 and NASA mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news. Ken Kremer
Soyuz has split into 3 modules 139.8 km above Earth. Crew parachutes to landing inside Descent Module at 9:22 pm ET Sept. 2, 2017. Credit: NASAExpedition 52 crew returns to Earth Sept. 2, 2017. Credit: NASAPeggy Whitson @AstroPeggy is 3rd place all-time for cumulative spacewalk time with 10 spacewalks totaling 60 hours, 21 minutes. Credit: NASA
All 5 layers of the Webb telescope sunshield installed at Northrop Grumman's clean room in Redondo Beach, California. The five sunshield membrane layers are each as thin as a human hair. Credits: Northrop Grumman Corp.
All 5 layers of the Webb telescope sunshield installed at Northrop Grumman’s clean room in Redondo Beach, California. The five sunshield membrane layers are each as thin as a human hair. Credits: Northrop Grumman Corp.
The complex multilayered sunshield that will protect the delicate optics and state of the art infrared science instruments of NASA’s James Webb Space Telescope (JWST) is now fully installed on the spacecraft bus in California, completing another major milestone on the path to launch, NASA announced.
Meanwhile a critical cryogenic cooling test of Webb’s mirrors and science instrument bus has commenced inside a giant chamber at NASA’s Johnson Space Center in Texas, marking another major milestone as the mammoth telescope comes together after years of development.
NASA’s $8.8 Billion James Webb Space Telescope is the most powerful space telescope ever built and is the scientific successor to the phenomenally successful Hubble Space Telescope (HST).
The sunshield layers work together to reduce the temperatures between the hot and cold sides of the observatory by approximately 570 degrees Fahrenheit. Each successive layer of the sunshield, which is made of Kapton, is cooler than the one below. The sunshield is in the clean room at Northrop Grumman Aerospace Systems in Redondo Beach, California. Credits: Northrop Grumman Corp.
The Webb telescopes groundbreaking tennis court sized sunshield subsystem consists of five layers of kapton that will keep the optics and instruments incredibly cool, by reducing the incoming sunside facing temperature more than 570 degrees Fahrenheit. Each layer is as thin as a human hair.
“The sunshield layers work together to reduce the temperatures between the hot and cold sides of the observatory by approximately 570 degrees Fahrenheit,” according to NASA. “Each successive layer of the sunshield is cooler than the one below.”
The painstaking work to integrate the five sunshield membranes was carried out in June and July by engineers and technicians working at the Northrop Grumman Corporation facility in Redondo Beach, California.
“All five sunshield membranes have been installed and will be folded over the next few weeks,” said Paul Geithner, deputy project manager – technical for the Webb telescope at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in a statement.
Deployment tests of the folded sunshield start in August.
Webb’s four research instruments cannot function without the essential cooling provided by the sunshield deployment.
Northrop Grumman designed the Webb telescope’s optics and spacecraft bus for NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which manages Webb.
Two sides of the James Webb Space Telescope (JWST). Credit: NASA
“This is a huge milestone for the Webb telescope as we prepare for launch,” said Jim Flynn, Webb sunshield manager, Northrop Grumman Aerospace Systems.
“The groundbreaking tennis court sized sunshield will shield the optics from heat and assist in providing the imaging of the formation of stars and galaxies more than 13.5 billion years ago.”
The 18-segment gold coated primary mirror of NASA’s James Webb Space Telescope is raised into vertical alignment in the largest clean room at the agency’s Goddard Space Flight Center in Greenbelt, Maryland, on Nov. 2, 2016. The secondary mirror mount booms are folded down into stowed for launch configuration. Credit: Ken Kremer/kenkremer.com
Webb is designed to look at the first light of the Universe and will be able to peer back in time to when the first stars and first galaxies were forming. It will also study the history of our universe and the formation of our solar system as well as other solar systems and exoplanets, some of which may be capable of supporting life on planets similar to Earth.
After successfully passing a rigorous series of vibration and acoustic environmental tests earlier this year at NASA Goddard in March, the mirror and instrument assembly was shipped to NASA Johnson in May for the cryo cooling tests.
“Those tests ensured Webb can withstand the vibration and noise created during the telescope’s launch into space. Currently, engineers are analyzing this data to prepare for a final round of vibration and acoustic testing, once Webb is joined with the spacecraft bus and sunshield next year,” says NASA.
The cryogenic cooling test will last 100 days and is being carried out inside the giant thermal vacuum known as Chamber A at the Johnson Space Center in Houston.
NASA’s James Webb Space Telescope sits in Chamber A at NASA’s Johnson Space Center in Houston awaiting the colossal door to close in July 2017 for cryogenic testing. Credits: NASA/Chris Gunn
“A combination of liquid nitrogen and cold gaseous helium will be used to cool the telescope and science instruments to their operational temperature during high-vacuum operations,” said Mark Voyton, manager of testing effort, who works at the NASA Goddard Space Flight Center in Greenbelt, Maryland.
Next year, the tennis-court sized sunshield and spacecraft bus will be combined to make up the entire observatory.
The first layer of the Webb telescope sunshield installed at Northrop Grumman’s clean room in Redondo Beach, California. Credits: Northrop Grumman Corp.
The Webb Telescope is a joint international collaborative project between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
Assembly of the Webb telescope is currently on target and slated to launch on an ESA Ariane V booster from the Guiana Space Center in Kourou, French Guiana in October 2018.
NASA and ESA are currently evaluating a potential launch scheduling conflict with ESA’s BepiColombo mission to Mercury.
Technicians work on the James Webb Space Telescope in the massive clean room at NASA’s Goddard Space Flight Center, Greenbelt, Maryland, on Nov. 2, 2016, as the completed golden primary mirror and observatory structure stands gloriously vertical on a work stand, reflecting incoming light from the area and observation deck. Credit: Ken Kremer/kenkremer.com
Watch for Ken’s onsite space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Artist’s concept of the James Webb Space Telescope (JWST) with Sunshield at bottom. Credit: NASA/ESA
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Learn more about the upcoming SpaceX Dragon CRS-12 resupply launch to ISS on Aug. 14, ULA Atlas TDRS-M NASA comsat on Aug. 18, 2017 Solar Eclipse, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:
Aug 11-14: “SpaceX CRS-12 and CRS-11 resupply launches to the ISS, Inmarsat 5, BulgariaSat 1 and NRO Spysat, EchoStar 23, SLS, Orion, Commercial crew capsules from Boeing and SpaceX , Heroes and Legends at KSCVC, ULA Atlas/John Glenn Cygnus launch to ISS, SBIRS GEO 3 launch, GOES-R weather satellite launch, OSIRIS-Rex, Juno at Jupiter, InSight Mars lander, SpaceX and Orbital ATK cargo missions to the ISS, ULA Delta 4 Heavy spy satellite, Curiosity and Opportunity explore Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
The Soyuz MS-05 rocket is launched with Expedition 52 flight engineer Sergei Ryazanskiy of Roscosmos, flight engineer Randy Bresnik of NASA, and flight engineer Paolo Nespoli of ESA (European Space Agency), Friday, July 28, 2017 at the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Joel Kowsky)
The Soyuz MS-05 rocket is launched with Expedition 52 flight engineer Sergei Ryazanskiy of Roscosmos, flight engineer Randy Bresnik of NASA, and flight engineer Paolo Nespoli of ESA (European Space Agency), Friday, July 28, 2017 at the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Joel Kowsky)
An all veteran multinational trio of astronauts and cosmonauts rocketed to orbit aboard a Russian Soyuz capsule and safely arrived at the International Space Station (ISS) after a fast track rendezvous on Friday, July 28.
NASA astronaut Randy Bresnik, Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of ESA (European Space Agency) docked at the orbiting outpost at 5:54 p.m. EDT (2154 GMT) Friday just six hours after departing our Home Planet.
The three crewmates launched aboard the Russian Soyuz MS-05 spacecraft from the Baikonur Cosmodrome in Kazakhstan during a typically hot mid-summers night at 9:41 p.m. Baikonur time, or 11:41 a.m. EDT, 1541 GMT, as the booster and Baikonur moved into the plane of the space station’s orbit. They blasted to space from the same pad as Yuri Gagarin, the first man in space.
The entire launch sequence aboard the Soyuz rocket performed flawlessly and delivered the Soyuz capsule to its targeted preliminary orbit flowing by the planned opening of the vehicles solar arrays and antennas.
The Russian Soyuz MS-05 carrying NASA astronaut Randy Bresnik, Sergey Ryazanskiy of the Russian space agency Roscosmos, and Paolo Nespoli of ESA (European Space Agency) docked to the International Space Station at 5:54 p.m. on Friday, July 28, 2017. Credits: NASA Television
Following a rapid series of orbit raising maneuvers, the Soyuz reached the ISS after 4 orbits and six hours to successfully complete all the rendezvous and docking procedures.
The Soyuz docked at the Earth-facing Russian Rassvet module as the spaceships were flying some 250 mi (400 km) over Germany.
The Soyuz MS-05 rocket is launched with Expedition 52 flight engineer Sergei Ryazanskiy of Roscosmos, flight engineer Randy Bresnik of NASA, and flight engineer Paolo Nespoli of ESA (European Space Agency), Friday, July 28, 2017 at the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Joel Kowsky)
Following the standard pressurization and leak checks, the hatches between the spacecraft and station were opened from inside the ISS at about 9:45 p.m. EDT.
The new trio of Bresnik, Ryazanskiy and Nespoli then floated one by one from the Soyuz into the station and restored the outpost to a full strength crew of six humans.
The veteran space flyers join Commander Fyodor Yurchikhin of Roscosmos and Flight Engineers Peggy Whitson and Jack Fischer of NASA who are already serving aboard.
Thus begins Expedition 52 aboard the million pound orbiting science complex.
The Soyuz MS-05 rocket is launched with Expedition 52 flight engineer Sergei Ryazanskiy of Roscosmos, flight engineer Randy Bresnik of NASA, and flight engineer Paolo Nespoli of ESA (European Space Agency), Friday, July 28, 2017 at the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Joel Kowsky)
This is the second space flight for both Bresnik and Ryazanskiy and the third for Nespoli.
Bresnik previously flew to the space station as a member of the STS-129 space shuttle Atlantis mission in November 2009. The 10 day mission delivered two Express Logistics Carriers (ELC racks) to the space station as part of approximately 30,000 pounds of replacement parts.
Bresnik performed two spacewalks for a total of 11 hours and 50 minutes during the STS-129 mission. He is slated to take command of the ISS as a member of Expedition 53.
The six person crew of Space Shuttle Atlantis walk out from crew quarters at 10:38 AM to greet the cheering crowd of media and NASA officials and then head out to pad 39 A to strap in for space launch with hours. Randy Bresnik is third from left. Credit: Ken Kremer/kenkremer.com
The new Expedition 52 crew will spend a four and a half month stint aboard the station and continue over 250 ongoing science investigations in fields such as biology, Earth science, human research, physical sciences and technology development.
Bresnik, Ryazanskiy and Nespoli are slated to stay aboard until returning to Earth in December.
Whitson, Fischer and Yurchikhin are in the home stretch of their mission and will retun to Earth in September. Shortly after their departure, NASA astronauts Mark Vande Hei and Joseph Acaba and Russian cosmonaut Alexander Misurkin will launch on the next Soyuz from Kazakhstan to join the Expedition 53 crew.
Whitson is the most experienced US astronaut with time in space. Her record setting cumulative time in space will exceed 600 days and include a 9 month stay on this flight upon her return to Earth.
She most recently launched to the ISS last year on Nov 17, 2016 aboard a Russian Soyuz capsule from the Baikonur Cosmodrome. This is her 3rd long duration stay aboard the station.
Whitson also holds the record for most spacewalks by a female astronaut. Altogether she has accumulated 53 hours and 23 minutes of EVA time over eight spacewalks.
The newly-expanded Expedition 52 crew expect to welcome a pair of unmanned US cargo ships carrying new research experiments and supplies, namely the SpaceX Dragon as soon as August and Orbital ATK Cygnus a month or two later, on NASA-contracted commercial resupply missions.
The SpaceX CRS-12 mission will carry investigations ”the crew will work on including a study developed by the Michael J. Fox Foundation of the pathology of Parkinson’s disease to aid in the development of therapies for patients on Earth. The crew will use the special nature of microgravity in a new lung tissue study to advance understanding of how stem cells work and pave the way for further use of the microgravity environment in stem cell research. Expedition astronauts also will assemble and deploy a microsatellite investigation seeking to validate the concept of using microsatellites in low-Earth orbit to support critical operations, such as providing lower-cost Earth imagery in time-sensitive situations such as tracking severe weather and detecting natural disasters.”
Watch for Ken’s onsite space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
In the future, derelict satellites could be grappled and removed from key orbits around Earth with a space tug using magnetic forces. Credit: Philippe Ogaki
After 50 years of sending rockets, satellites, and payloads into orbit, humanity has created something of a “space junk” problem. Recent estimates indicate that there are more than 170 million pieces of debris up there, ranging in size from less than 1 cm (0.4 in) to a few meters in diameter. Not only does this junk threaten spacecraft and the ISS, but collisions between bits of debris can cause more to form, a phenomena known as the Kessler Effect.
And thanks to the growth of the commercial aerospace industry and the development of small satellites, things are not likely to get any less cluttered up there anytime soon. Hence why multiple strategies are being explored to clean up the space lanes, ranging from robotic arms and nets to harpoons. But in what may be the most ambitious plan to date, the ESA has proposed creating space tugs with powerful magnets to yank debris out of orbit.
The concept comes from Emilien Fabacher, a researcher from the Institut Supérieur de l’Aéronautique et de l’Espace at the University of Toulouse, France. His concept for a magnetic tug seeks to address one type of space debris in particular – inoperable satellites. These uncontrolled, rapidly spinning objects often weigh up to several tons, and are therefore one of the most significant collision hazards there is.
Illustration showing the problem of space debris. Credit: ESA
When applied to the problem of orbital debris, magnetic attraction is an attractive solutions for the safe deorbiting of spent satellites. For starters, it relies on technology that is standard issue aboard many low-orbiting satellites, which is known as magnetorquers. These electromagnets allow satellites to adjust their orientation using the Earth’s magnetic field. Hence, debris-chasing satellites would not need to be specially equipped in advance.
What’s more, this same magnetic attraction or repulsion technology is being considered as a safe method for allowing multiple satellites to maintain close formations in space. Such satellites – like NASA’s Magnetospheric Multiscale mission (MMS), the Landsat 7 and the Earth Observing-1 satellites, and the ESA’s upcoming LISA mission – are either operational or soon will be around Earth.
Because of this, this kind of magnetic attraction technology presents a safe and effective alternative for deorbiting space junk. As Fabacher explained in a recent ESA press release:
“With a satellite you want to deorbit, it’s much better if you can stay at a safe distance, without needing to come into direct contact and risking damage to both chaser and target satellites. So the idea I’m investigating is to apply magnetic forces either to attract or repel the target satellite, to shift its orbit or deorbit it entirely.”
Artist’s impression of the ESA’s proposed Darwin mission, six formation-flying satellites that would look for exoplanets. Credit: ESA/Medialab
The concept emerged out of a conversation Fabacher had with experts from the ESA’s technical center in the Netherlands. As part of his PhD research, he was looking into how magnetic guidance, navigation and control techniques would work in practice. This led to a discussion about how similar technology could allow swarms of satellites to attract and remove debris from orbit.
After making some calculations that combined a rendezvous simulator with magnetic interaction models, and also taking account the ever-changing state of Earth’s own magnetosphere, Fabacher and his colleagues realized they had a working concept. “The first surprise was that it was indeed possible, theoretically – initially we couldn’t be sure, but it turns out that the physics works fine,” he said.
To break it down, the chaser satellites would generate a strong magnetic field using superconducting wires that are cooled to cryogenic temperatures. These satellites would also rely on magnetic fields to maintain precise flying formations, thus allowing a swarm of chaser satellites the ability to deal with multiple pieces of debris, or to coordinate and guide debris to a specific location.
According to Finn Ankersen – an ESA expert in rendezvous and docking and formation flight – these magnetic tugs would also be able to remove space debris with a very high level of precision. “This kind of contactless magnetic influence would work from about 10–15 meters out, offering positioning precision within 10 cm with attitude precision [of] 1 – 2º,” he said.
Why Space Debris Mitigation is needed. Click for animation. Credit: ESA
The concept is being developed with support provided by the ESA’s Networking/Partnering Initiative, a program that offers support to universities and research institutes for the sake of developing space-related technologies. And it comes at a time when the issue of space debris is becoming increasingly worrisome.
Left unchecked, space debris is likely to become a very serious hazard in the coming years and decades. Already, it is estimated that the small satellite market will grow by $5.3 billion in the next decade (according to Space Works and Eurostat) and many private companies are looking to provide regular launch services to accommodate that growth.
If we intend to begin making a return to the Moon and mounting missions to Mars, we need to make sure the space lanes are clear! And given the importance of the International Space Station to scientific research and international collaboration, and with companies like Bigelow Aerospace looking to establish space habitats in orbit, something has to be done about this problem before it gets completely out of control!
Who knows? Maybe a small fleet or magnetic tugs is just what we need to clean up this mess!
An artists impression of a lunar explosion - caused by the impact of a meteorite. Credit: NASA/Jennifer Harbaugh
In February of 2015, the National Observatory of Athens and the European Space Agency launched theNear-Earth object Lunar Impacts and Optical TrAnsients (NELIOTA) project. Using the 1.2 meter telescope at the Kryoneri Observatory, the purpose of this project is to the determine the frequency and distribution of Near-Earth Objects (NEOs) by monitoring how often they impact the Moon.
Last week, on May 24th, 2017, the ESA announced that the project had begun to detect impacts, which were made possible thanks to the flashes of light detected on the lunar surface. Whereas other observatories that monitor the Moon’s surface are able to detect these impacts, NELIOTA is unique in that it is capable of not only spotting fainter flashes, but also measuring the temperatures of they create.
Projects like NELIOTA are important because the Earth and the Moon are constantly being bombarded by natural space debris – which ranges in size from dust and pebbles to larger objects. While larger objects are rare, they can cause considerable damage, like the 20-meter object that disintegrated above the Russian city of Chelyabinsk in February of 2013, causing extensive injuries and destruction of property.
The two main smoke trails left by the Russian meteorite as it passed over the city of Chelyabinsk. Credit: AP Photo/Chelyabinsk.ru
What’s more, whereas particulate matter rains down on Earth and the Moon quite regularly, the frequency of pebble-sized or meter-sized objects is not well known. These objects remain too small to be detected by telescopes directly, and cameras are rarely able to picture them before they break up in Earth’s atmosphere. Hence, scientists have been looking for other ways to determine just how frequent these potentially-threatening objects are.
One way is to observe the areas of the lunar surface that are not illuminated by the Sun, where the impact of a small object at high speed will cause a bright flash. These flashes are created by the object burning up on impact, and are bright enough to be seen from Earth. Assuming the objects have a density and velocity common to NEOs, the brightness of the impact can be used to determine the size and mass of the object.
As Detlef Koschny – the co-manager of the near-Earth object segment of the ESA’s Space Situational Awareness Program, and a scientist in the Science Support Office – said in an ESA press release:
“These observations are very relevant for our Space Situational Awareness program. In particular, in the size range we can observe here, the number of objects is not very well known. Performing these observations over a longer period of time will help us to better understand this number.“
Tiny pieces of rock striking the Moon’s surface were witnessed by the NELIOTA project, which was monitoring the dark side of the Moon. Credit: NELIOTA project
After being taken offline in 2016 for the sake of making upgrades, the NELIOTA project officially began conducting operations on March 8th, 2017. Using this refurbished telescope, which is operated by the National Observatory of Athens, NELIOTA is capable of detecting flashes that are much fainter than any current, small-aperture, lunar monitoring telescopes.
The telescope does this by observing the Moon’s night hemisphere whenever it is above the horizon and between phases. At these times – i.e. between a New Moon and the First Quarter, or between the Last Quarter and a New Moon – the surface is mostly dark and flashes are most visible. Incoming light is then split into two colors and the data is recorded by two advanced digital cameras that operate in different color ranges.
This data is then analyzed by automated software, which extrapolates temperatures based on the color data obtained by the cameras. As Alceste Bonanos – the Principal Investigator for NELIOTA – explained, all this sets the 1.2 meter telescope apart:
“Its large telescope aperture enables NELIOTA to detect fainter flashes than other lunar monitoring surveys and provides precise color information not currently available from other project. Our twin camera system allows us to confirm lunar impact events with a single telescope, something that has not been done before. Once data have been collected over the 22-month long operational period, we will be able to better constrain the number of NEOs (near-Earth objects) in the decimetre to metre size range.
Images showing the lunar impact flash caught by NELIOTA. Credit: NELIOTA project
The NELIOTA project scientists are currently collaborating with the Science Support Office of ESA to analyze the flashes and measure the temperatures of each flash. From this, they hope to be able to make accurate estimates of the mass and size of each impactor, which they will further corroborate by analyzing the size of the craters these impacts leave behind.
The study of impacts on the Moon will ultimately let scientists know exactly how often larger objects are raining down on Earth. Armed with this information, we will be able to make better predictions on when and how a potentially-threatening object could be entering our atmosphere. As the Chelyabinsk meteor demonstrated, one of the greatest dangers posed by meteorites is a general lack of preparedness. Where people can be forewarned, injury, damage and even deaths can be prevented.
NELIOTA is also contributing to public outreach and education through a number of initiatives. These include public tours of the Kryoneri Observatory – in which the details of the NELIOTA project are shared – as well as presentations to students and the general public about Near-Earth Asteroids. The project team are also training two PhD students in how to operate the Kryoneri telescope and conduct lunar observing, thus creating the next-generation of NEO observers.
This summer (Friday, June 30th), the Observatory will also be hosting a public event to coincide with Asteroid Day 2017. This international event will feature presentations, speeches and educational seminars hosted by astronomical institutions and organizations from all around the world. Save the date!
