Missions Archives

October 19, 2016 by Matt Williams

Forget Mars, Now You Can Kickstart an Antimatter Propulsion System to Another Star!

Artist's concept of Antimatter propulsion system. Credit: NASA/MFSC

When it comes to the future of space exploration, one of the biggest questions is, “how and when will we travel to the nearest star?” And while space agencies have been pondering this question and coming up with proposals for decades, none of them have advanced beyond the theory stage. For the most part, their efforts has been focused on possible missions to Mars and the outer Solar System.

But there are some people, like Dr. Gerald Jackson, who are working towards making an interstellar mission possible in the near future. He and his research team, which have been funded by NASA in the past, are looking to create an antimatter engine that will be capable of reaching (or exceeding) 5% the speed of light. Towards this end, they have launched a Kickstarter campaign to fund their efforts.

As advanced propulsion concepts go, antimatter has quite a lot going for it. As propulsion goes, it has the highest specific energy of any known method, 100 times more than fission/fusion reactions, and 10 billion times more than chemical propellants. It is also the most fuel-efficient, requiring mere milligrams of antimatter to produce the same amount of energy as tons of chemical fuel.

Typically, this theoretical concept relies on the collision between hydrogen and antihydrogen (which have the same mass but opposite charge) to generate thrust. This process unleashes energy and a shower of particles (pions and muons), which can be channeled by a magnetic nozzle to generate thrust.

And while laboratories like CERN have been producing antimatter, and research is being conducted on large-scale storage, no propulsion systems exist that could turn antimatter into thrust. Dr. Jackson, a graduate of Cornell University, is hoping to change that. Before entering the private sector, Jackson worked as an accelerator physicist at the Fermi National Accelerator Laboratory for 14 years.

In 2002, he co-founded a limited-liability company (HBar Technologies) for the sake of developing commercial markets for antimatter. In 2002, NASA’s Institute for Advanced Concepts (NIAC) awarded Dr. Jackson and his company $75,000 to develop a mission concept that could traverse 250 AUs of space within 10 years time, and with a fuel supply of 10 kg.

These specifications essentially called for the creation of an antimatter rocket that could travel as far as the heliopause within a decade’s time. The result was a propulsion concept that relied on a beam that would fire focused antiprotons onto a sail to generate propulsion. This sail would measure 5 meters in diameter and be composed of a carbon backing on one side and uranium foil on the other (measuring 15 and 296 microns thick, respectively).

The solar system and its nearby galactic neighborhood are illustrated here on a logarithmic scale extending (from < 1 to) 1 million Astornomical Units (AU). Credit: NASA/JPL — *Illustration of the solar system and its nearby galactic neighborhood on a logarithmic scale extending (from < 1 to) 1 million AU. Credit: NASA/JPL*

When a pulse of antiprotons is annihilated against a small section of the uranium side, the resulting fission causes momentum. As Dr. Jackson explained to Universe Today via email:

“Note that antiprotons have a negative electrical charge, similar to an electron. When the antiprotons enter the sail, they displace an electron orbiting an uranium nucleus. Because antiprotons and electrons do not share any quantum numbers, the antiproton immediately cascades down into the atomic ground state, causing a high probability of interaction between the antiproton and either a proton or neutron within the nucleus.

“On average, a fission event results in the creation of two daughter nuclei of roughly equal mass. These daughters travel in opposite directions with a kinetic energy of 1 MeV per proton or neutron. Because the daughters are charged, the one travelling further into the sail is absorbed and transfers is forward momentum. The other daughter flies into space with an exhaust velocity of 4.6% of lightspeed. This selective transfer of momentum is thrust.”

Unfortunately, due to the budget environment of the time, the NIAC was forced to cancel its funding after a second round had been granted. Because of this, Dr. Jackson and his colleagues are now seeking public support so that they may finish their work on the experimental sail and prepare it for exposure to an antiproton beam.

Diagram showing Hbar's concept for a antimatter-driven propulsion system. Credit: antimatterdrive.org — *Diagram showing Hbar’s concept for a antimatter-driven propulsion system. Credit: antimatterdrive.org*

Much like Project Starshot (whom they acknowledge on their campaign page), Jackson and his team are looking to produce an interstellar mission proposal that does not involve shortcuts (i.e. warp drive, wormholes, star gates, etc.). Starshot, as you may recall, calls for a wafer craft and a laser-driven lightsail that would be capable of reaching speeds of up to 20% the speed of light, thus making the journey to Alpha Centauri in 20 years.

In the same vein, a antiproton-driven sail that could reach speeds of 5% the speed of light or more would be capable of making it to Alpha Centauri (or Proxima Centauri) in about 90 years time. All the while, the science behind it would remain within the realm of established physics, being consistent with Newton’s Laws of Motion and Einstein’s Theory of Special Relativity.

“The revolutionary aspect of the antimatter-driven sail is that the antimatter is not the fuel, but rather the spark plug that initiates fission reactions,” said Jackson. “Because the fission reactions can produce thrust without heavy shielding or other structures, the mass of the propulsion system can be comparable to the mass of the instrument package.”

Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org — *Project Starshot, an initiative sponsored by the Breakthrough Foundation, is another concept for making humanity’s first interstellar voyage. Credit: breakthroughinitiatives.org*

To see their project through, Jackson and his colleagues are hoping to raise $200,000. Should they prove successful, they hope to mount follow-up campaigns to finance a series of validation experiments, storage demonstrations, and mission details. In the end, their goal is nothing less than making antimatter propulsion a reality, which they hope will one day lead interstellar mission.

“We expect that these campaigns will provide the data needed to convince people to fund full scale antimatter production and an actual mission to a nearby solar system,” Jackson added. “The goal of those early interstellar missions is to provide information about these other solar systems, such as whether they are habitable or inhabited. If the latter, we will want to study or interact with those life forms in follow-on missions. If habitable and not inhabited, we need sufficient information to assure the success of a manned migratory mission.”

As of the penning of this article, Jackson and his colleagues have raised $672 of their $200,000 goal. However, the campaign launched only a few days ago and will remain open for another 25 days. For those interesting in following their progress, or have an interest in donating to their cause, check out the links below.

Further Reading: Kickstarter, Antima:tterDrive

October 19, 2016October 20, 2016 by Bob King

Europe’s Orbiter is Safely at Mars, but No Word from the Lander

This artist's view shows the European Space Agency's Schiaparelli lander on Mars. It's unclear whether the landing was successful. Signals were received during its descent but then suddenly cut off. Mission control is working on the data now and will have an update on the status of the probe tomorrow morning Oct. 20. Credit: ESA/ATG medialab

Schiaparelli on Mars. Credit: ESA/ATG medialab — This artist’s view shows the European Space Agency’s Schiaparelli lander on Mars. It’s unclear whether the landing was successful. Signals were received during its descent but then suddenly cut off. Mission control is working on the data now and will have an update on the status of the probe tomorrow morning Oct. 20. Credit: ESA/ATG medialab

Good news and bad news. First the good. After a seven-month and 300 million mile (483 million km) journey, the Trace Gas Orbiter (TGO) successfully achieved orbit around Mars today. A signal spike appeared out of the noise about 12:35 p.m. EDT to great applause and high-fives at ESA’s European Space Operations Center in Darmstadt, Germany.

Hugs in the control room when the signal from the Trace Gas Orbiter was received this morning, signaling that the spacecraft had achieved orbit around Mars. Credit: ESA Livestream — Joy in the control room when the signal from the Trace Gas Orbiter was received this morning, signaling that the spacecraft had achieved orbit around Mars. Credit: ESA Livestream

Two hours later, news of the lander arrived. Not so good but to be fair, it’s still too early to tell. Schiaparelli broadcast a signal during its descent to the Red Planet that was received here on Earth and by the orbiting Mars Express. All well and good. But then mid-transmission, the signal cut out.

Paolo Ferri, head of ESA’s mission operations department, called the news “not good signs” but promised that his team would be analyzing the data through the night to determine the status of the lander. Their findings will be shared around mid-morning Friday Central European Time (around 5 a.m. EDT).

Three days ago, Schiaparelli separated from the orbiter and began a three-day coast to Mars. It entered the atmosphere today at an altitude of 76 miles (122 km) and speed of 13,049 mph (21,000 km/hr), protected from the hellish heat of re-entry by an aerodynamic heat shield.

Simulated sequence of the 15 images that the descent camera Schiaparelli module should have taken during its descent to Mars this morning. In the simulated images shown here, the first was made from 3 km up. The camera took images every 1.5 seconds with the final image in this at ~1.5 km. Depending on Schiaparelli’s actual descent speed, the final image may have been snapped closer to the surface. The views were generated from images taken by NASA’s Mars Reconnaissance Orbiter of the center of Schiaparelli's landing ellipse, and represent the views expected at each altitude. Copyright spacecraft: ESA/ATG medialab; simulated views based on NASA MRO/CTX images (credit: NASA/JPL/MRO); landing ellipse background image: Mars Odyssey; simulation: ESA — Simulated sequence of the 15 images that the descent camera Schiaparelli module should have taken during its descent to Mars this morning. In the simulated images shown here, the first was made from 3 km up. The camera had planned to take images every 1.5 seconds with the final image in this at ~1.5 km. Depending on Schiaparelli’s actual descent speed, the final image may have been snapped closer to the surface. The views were generated from images taken by NASA’s Mars Reconnaissance Orbiter of the center of Schiaparelli’s landing ellipse, and represent the views expected at each altitude. Copyright spacecraft: ESA/ATG medialab; simulated views from NASA images (credit: NASA/JPL/MRO); landing ellipse background image: Mars Odyssey; simulation: ESA

If all went well, at 6.8 miles (11 km) altitude, it would have deployed its parachute and moments later, dropped the heat shield. At 0.7 miles (1.2 km) above the surface, the lander would have jettisoned the chute and rear protective cover and fired its nine retrorockets while plummeting to the surface at 155 mph (255 mph). 29 seconds later, the thrusters would have shut off with Schiaparelli dropping the remaining 6.5 feet (2 meters) to the ground. Total elapsed time: just under 6 minutes.

For now, have hope. Given that Schiaparelli was primarily a test of landing technologies for future Mars missions, whatever happened, everything we learn from this unexpected turn of events will be invaluable. You can continue to follow updates on ESA’s Livestream.

** Update Oct. 20: It appears that the thrusters on Schiaparelli may have cut out too soon, causing the lander to drop from a higher altitude. In addition, the ejection of the parachute and back heat shield may have happened earlier than expected.

This from ESA:

“The data have been partially analyzed and confirm that the entry and descent stages occurred as expected, with events diverging from what was expected after the ejection of the back heat shield and parachute. This ejection itself appears to have occurred earlier than expected, but analysis is not yet complete.

The thrusters were confirmed to have been briefly activated although it seems likely that they switched off sooner than expected, at an altitude that is still to be determined.”

October 17, 2016October 18, 2016 by Nancy Atkinson

MAVEN Takes This Trippy, Nightglowing Photo of Mars in UV

This image of the Mars night side shows ultraviolet emission from nitric oxide. These emissions track the recombination of atomic nitrogen and oxygen produced on the dayside, and reveal the circulation patterns of the atmosphere. MAVEN's Imaging UltraViolet Spectrograph obtained this image of Mars on May 4, 2016 during late winter in Mars Southern Hemisphere. Credits: NASA/MAVEN/University of Colorado

Mars’ atmosphere is about 100 times thinner than Earth’s, but there’s still a lot going on in that wispy, carbon dioxide Martian air. The MAVEN spacecraft recently took some exceptional images of Mars using its Imaging UltraViolet Spectrograph (IUVS), revealing dynamic and previously invisible subtleties.

MAVEN took the first-ever images of nightglow on Mars. You may have seen nightglow in images of Earth taken by astronauts on the International Space Station as a dim greenish light surrounding the planet. Nightglow is produced when oxygen and nitrogen atoms collide to form nitric oxide. This is ionized by ultraviolet light from the Sun during the day, and as it travels around to the nightside of the planet, it will glow in ultraviolet.

An image of nightglow in Earth's atmosphere, taken from the International Space Station. Credit: NASA. — An image of nightglow in Earth’s atmosphere, taken from the International Space Station. Credit: NASA.

“The planet will glow as a result of this chemical reaction,” said Nick Schneider, from the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, speaking today at the American Astronomical Society Division for Planetary Sciences meeting. “This is a common planetary reaction that tells us about the transport of these ingredients and around the planet and show how winds circulate at high altitudes.”

MAVEN’s images show evidence of strong irregularities in Mars’ high altitude winds and circulation patterns and Schneider said these first images will lead to an improved understanding of the circulation patterns that control the behavior of the atmosphere from approximately 37 to 62 miles (about 60 to 100 kilometers) high.

MAVEN's Imaging UltraViolet Spectrograph obtained these images of rapid cloud formation on Mars on July 9-10, 2016. Mars’ prominent volcanoes, topped with white clouds, can be seen moving across the disk and show how rapidly and extensively the clouds topping the volcanoes form in the afternoon. Credits: NASA/MAVEN/University of Colorado — MAVEN’s Imaging UltraViolet Spectrograph obtained these images of rapid cloud formation on Mars on July 9-10, 2016. Mars’ prominent volcanoes, topped with white clouds, can be seen moving across the disk and show how rapidly and extensively the clouds topping the volcanoes form in the afternoon. Credits: NASA/MAVEN/University of Colorado

MAVEN’s ultraviolet images also provide insight into cloud formation and ozone in Mars atmosphere.

The images show how water ice clouds form, especially in the afternoon, over the four giant volcanoes on Mars in the Tharsis region. Cloud formation in the afternoon is a common occurrence on Earth, as convection causes water vapor to rise.

“Water ice clouds are very common on Mars and they can tell us about water inventory on the planet,” Schneider said. “In these images you can see an incredible expansion of the clouds over the course of seven hours, forming a cloud bank that must be a thousand miles across.”

He added that this is just the kind of info scientists want to be plugging in to their circulation models to study circulation and the chemistry of Mars’ atmosphere. “This is helping us advance our understanding in these areas, and we’ll be able to study it with MAVEN through full range of Mars’ seasons.”

MAVEN's Imaging UltraViolet Spectrograph obtained images of rapid cloud formation on Mars on July 9-10, 2016. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. Mars’ tallest volcano, Olympus Mons, appears as a prominent dark region near the top of the image, with a small white cloud at the summit that grows during the day. Three more volcanoes appear in a diagonal row, with their cloud cover (white areas near center) merging to span up to a thousand miles by the end of the day. Credits: NASA/MAVEN/University of Colorado — MAVEN’s Imaging UltraViolet Spectrograph obtained images of rapid cloud formation on Mars on July 9-10, 2016. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. Mars’ tallest volcano, Olympus Mons, appears as a prominent dark region near the top of the image, with a small white cloud at the summit that grows during the day. Three more volcanoes appear in a diagonal row, with their cloud cover (white areas near center) merging to span up to a thousand miles by the end of the day.
Credits: NASA/MAVEN/University of Colorado

Schneider explained that MAVEN’s unique orbit allows it to get views of the planet that other orbiters don’t have. One part of its elliptical orbit takes it high above the planet that allows for global views, but it still orbits fast enough to get multiple views as Mars rotates over the course of a day.

“We get to see daily events evolve over time because we return to that orbit every few hours,” he said.

This ultraviolet image near Mars’ South Pole was taken by MAVEN on July 10 2016 and shows the atmosphere and surface during southern spring. The white region centered on the pole is frozen carbon dioxide (dry ice) on the surface. Pockets of ice are left inside craters as the polar cap recedes in the spring, giving its edge a rough appearance. High concentrations of atmospheric ozone appear magenta in color, and the wavy edge of the enhanced ozone region highlights wind patterns around the pole. Credits: NASA/MAVEN/University of Colorado — This ultraviolet image near Mars’ South Pole was taken by MAVEN on July 10 2016 and shows the atmosphere and surface during southern spring. The white region centered on the pole is frozen carbon dioxide (dry ice) on the surface. Pockets of ice are left inside craters as the polar cap recedes in the spring, giving its edge a rough appearance. High concentrations of atmospheric ozone appear magenta in color, and the wavy edge of the enhanced ozone region highlights wind patterns around the pole.
Credits: NASA/MAVEN/University of Colorado

In addition, dayside ultraviolet imagery from the spacecraft shows how ozone amounts change over the seasons. Ozone is destroyed when water vapor is present, so ozone accumulates in the winter polar region where the water vapor has frozen out of the atmosphere. The images show ozone lasting into spring, indicating that global winds are constraining the spread of water vapor from the rest of the planet into winter polar regions.

Wave patterns in the ozone images show wind pattern, as well, helping scientists to study the chemistry and global circulation of Mars’ atmosphere.

Additional reading:
NASA

October 16, 2016October 16, 2016 by Ken Kremer

Antares Return to Flight Set for Magnificent Monday Night Launch – Watch Live

The Orbital ATK Antares rocket, with the Cygnus OA-5 spacecraft onboard, is raised into the vertical position on launch Pad-0A for planned launch on Oct. 17, 2016, at NASA's Wallops Flight Facility in Virginia. Credit: Ken Kremer/kenkremer

NASA WALLOPS FLIGHT FACILITY, VA – The ‘Return to Flight’ blastoff of Orbital ATK’s upgraded Antares rocket will have to wait one more day to come to fruition with a magnificent Monday night launch – after a technical scrub was called this afternoon, Oct. 16, at NASA’s Virginia launch base due to a faulty cable.

The launch potentially offers a thrilling skyshow to millions of US East Coast spectators if all goes well.

Antares Launch Viewing Map. This “first-sight” map indicates potential to see Orbital ATK’s Antares rocket in the minutes following its launch on the OA-5 mission to the ISS on October 16, 2016. Credit: Orbital ATK

Despite picture perfect Fall weather, technical gremlins intervened to halt Sunday nights planned commercial cargo mission for NASA carrying 2.5 tons of science and supplies bound for the International Space Station (ISS).

The launch of the Orbital ATK CRS-5 mission is now scheduled for October 17 at 7:40 p.m. EDT, from the Mid-Atlantic Regional Spaceport pad 0A at NASA’s Wallops Flight Facility on Virginia’s picturesque Eastern shore.

You can watch the launch live on NASA TV as well as the agency’s website beginning at 6:30 p.m. EDT Oct 17.

Mondays liftoff is slated to take place approximately 23 minutes earlier then Sunday’s hoped for time of 8:03 p.m. EDT in order to match the moment when the orbital plane of the station passes on NASA Wallops.

The weather outlook on Monday remains extremely favorable with a 95 percent chance of acceptable conditions at launch time.

A nearly full moon has risen over Antares the past few days at the launch pad.

2 Moons and Antares on the launch pad on the evening of Oct. 15, 2016 at NASA's Wallops Flight Facility in Virginia in this water reflection shot. Liftoff of the OA-5 mission to the ISS is planned for Oct. 17, 2016. Credit: Ken Kremer/kenkremer — 2 Moons and Antares on the launch pad on the evening of Oct. 15, 2016 at NASA’s Wallops Flight Facility in Virginia in this water reflection shot. Liftoff of the OA-5 mission to the ISS is planned for Oct. 17, 2016. Credit: Ken Kremer/kenkremer

Announcement of the launch scrub of the mission – also known as OA-5 – came just as the six hour countdown was set to begin after engineers discovered the bad cable.

“Today’s launch of Orbital ATK’s Antares rocket is postponed 24 hours due to a ground support equipment (GSE) cable that did not perform as expected during the pre-launch check out,” officials at NASA Wallops said.

The faulty cable was a component of the rocket’s hold down system at the pad, Orbital ATK officials told Universe Today after the scrub was announced.

Technicians have spares on hand and are working now to replace the cable in time to permit a Monday evening launch.

“We have spares on hand and rework procedures are in process. The Antares and Cygnus teams are not currently working any technical issues with the rocket or the spacecraft.”

Besides the cable the rocket is apparently in perfect shape.

“The Antares and Cygnus teams are not currently working any technical issues with the rocket or the spacecraft.”

Antares launches have been on hold for two years after it was grounded following its catastrophic failure just moments after liftoff on Oct. 28, 2014 that doomed the Orb-3 resupply mission to the space station – as witnessed by this author.

Orbital ATK’s Antares commercial rocket had to be overhauled with the completely new RD-181 first stage engines- fueled by LOX/kerosene – following the destruction of the Antares rocket and Cygnus supply ship two years ago.

The 14 story tall commercial Antares rocket also will launch for the first time in the upgraded 230 configuration – powered by new Russian-built first stage engines designed and manufactured by Energomesh.

The 133-foot-tall (40-meter) Antares was rolled out to pad 0A on Thursday, Oct. 13 – three days prior to Sunday’s intended launch date. It was raised to the vertical launch position on Friday.

The two stage Antares will carry the Orbital OA-5 Cygnus cargo freighter to orbit on a flight bound for the ISS and its multinational crew of astronauts and cosmonauts.

The launch marks the first nighttime liftoff of the Antares – and it could be visible up and down the eastern seaboard if weather and atmospheric conditions cooperate to provide a spectacular viewing opportunity to the most populated region in North America.

The Cygnus spacecraft for the OA-5 mission is named the S.S. Alan G. Poindexter in honor of former astronaut and Naval Aviator Captain Alan Poindexter.

Under the Commercial Resupply Services (CRS) contract with NASA, Orbital ATK will deliver approximately 28,700 kilograms of cargo to the space station. OA-5 is the sixth of these missions.

Antares and the Moon at the pad at NASA's Wallops Flight Facility in Virginia as seen from a boat off shore in the Atlantic Ocean on Oct. 15, 2016. Credit: © Patrick J. Hendrickson / Highcamera.com — Antares and the Moon at the pad at NASA’s Wallops Flight Facility in Virginia as seen from a boat off shore in the Atlantic Ocean on Oct. 15, 2016. Credit: © Patrick J. Hendrickson / Highcamera.com

Watch for Ken’s continuing Antares/Cygnus mission and launch reporting. He will be reporting from on site at NASA’s Wallops Flight Facility, VA during the launch campaign.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

October 15, 2016November 5, 2016 by Bob King

The Moon Is Getting Slammed Way More Than We Thought

A brand new crater on the Moon! This new 12 meter (39 foot) diameter impact crater formed between 25 October 2012 and 21 April 2013 Credit: NASA/GSFC/Arizona State University].

Animation of a temporal pair of the new 39-foot (12-meter) impact crater on the moon photographed by NASA's Lunar Reconnaissance Orbiter Credit: NASA/GSFC/Arizona State University — Animation of a temporal pair of the new 39-foot (12-meter) impact crater on the moon photographed by NASA’s Lunar Reconnaissance Orbiter Credit: NASA/GSFC/Arizona State University

We often hear how the Moon’s appearance hasn’t changed in millions or even billions of years. While micrometeorites, cosmic rays and the solar wind slowly grind down lunar rocks, the Moon lacks erosional processes such as water, wind and lurching tectonic plates that can get the job done in a hurry.

After taking the first boot print photo, Aldrin moved closer to the little rock and took this second shot. The dusty, sandy pebbly soil is also known as the lunar ‘regolith’. Click to enlarge. Credit: NASA — One of a series of photos Apollo 11 astronaut Edwin Aldrin made of his bootprint in the dusty, sandy lunar soil, called regolith. Based on a newy study, the impression may disappear in a few tens of thousands of years instead a few million. Credit: NASA

Remember Buzz Aldrin’s photo of his boot print in the lunar regolith? It was thought the impression would last up to 2 million years. Now it seems that estimate may have to be revised based on photos taken by the Lunar Reconnaissance Orbiter (LRO) that reveal that impacts are transforming the surface much faster than previously thought.

Distribution of new impact craters (yellow dots) discovered by analyzing 14,000 NAC temporal pairs. The two red dots mark the location of the 17 March 2013 and the 11 September 2013 impacts that were recorded by Earth-based video monitoring [NASA/GSFC/Arizona State University] — This map shows the distribution of new impact craters (yellow dots) discovered by analyzing 14,000 narrow-angle camera (NAC) temporal pairs. The two red dots mark the location of the March 17, 2013 and September 11, 2013 impacts that were recorded by Earth-based video monitoring. LRO’s mission was **recently extended** an addition two years through September 2018. Credit: NASA/GSFC/ASU

The LRO’s high resolution camera, which can resolve features down to about 3 feet (1-meter) across, has been peering down at the Moon from orbit since 2009. Taking before and after images, called temporal pairs, scientists have identified 222 impact craters that formed over the past 7 years. The new craters range from 10 feet up to 141 feet (3-43 meters) in diameter.

By analyzing the number of new craters and their size, and the time between each temporal pair, a team of scientists from Arizona State University and Cornell estimated the current cratering rate on the Moon. The result, published in Nature this week, was unexpected: 33% more new craters with diameters of at least 30 feet (10 meters) were found than anticipated by previous cratering models.

their brightest recorded flash occurred on 17 March 2013 with coordinates 20.7135°N, 335.6698°E. Since then LRO passed over the flash site and the NAC imaged the surrounding area; a new 18 meter (59 feet) diameter crater was found by comparing images taken before and after the March date. — LRO before and after images of an impact event on March 17, 2013. The newly formed crater is 59 feet (18 meters) in diameter. Subsurface regolith not exposed to sunlight forms a bright halo around the new crater. There also appears to be a larger nimbus of darker reflectance material visible much further beyond but centered on the impact. Credit: NASA/GSFC/Arizona State University

Similar to the crater that appeared on March 17, 2013 (above), the team also found that new impacts are surrounded by light and dark reflectance patterns related to material ejected during crater formation. Many of the larger impact craters show up to four distinct bright or dark reflectance zones. Nearest to the impact site, there are usually zone of both high and low reflectance. These two zones likely formed as a layer of material that was ejected from the crater during the impact shot outward to about 2½ crater diameters from the rim.

An artist's illustration of a meteoroid impact on the Moon. (Credit: NASA). — An artist’s illustration of a meteoroid impact on the Moon. Impacts dig up fresh material from below as well as send waves of hot rock vapor and molten rock across the lunar landscape, causing a much faster turnover of the moon soil than previously thought. Credit: NASA

From analyzing multiple impact sites, far flung ejecta patterns wrap around small obstacles like hills and crater rims, indicating the material was traveling nearly parallel to the ground. This kind of path is only possible if the material was ejected at very high speed around 10 miles per second or 36,000 miles per hour! The jet contains vaporized and molten rock that disturb the upper layer of lunar regolith, modifying its reflectance properties.

How LRO creates temporal pairs and scientists use them to discover changes on the moon’s surface.

In addition to discovering impact craters and their fascinating ejecta patterns, the scientists also observed a large number of small surface changes they call ‘splotches’ most likely caused by small, secondary impacts. Dense clusters of these splotches are found around new impact sites suggesting they may be secondary surface changes caused by material thrown out from a nearby primary impact. From 14,000 temporal pairs, the group identified over 47,000 splotches so far.

Example of a low reflectance (top) and high reflectance (bottom) splotch created either by a small impactor or more likely from secondary ejecta. In either case, the top few centimeters of the regolith (soil) was churned [NASA/GSFC/Arizona State University]. — Here are two examples of a low reflectance (top) and high reflectance (bottom) splotch created either by a small impactor or more likely from secondary ejecta. In either case, the top few inches of the regolith (soil) was churned Credit: NASA/GSFC/Arizona State University

Based on estimates of size, depth and frequency of formation, the group estimated that the relentless churning caused by meteoroid impacts will turn over 99% of the lunar surface after about 81,000 years. Keep in mind, we’re talking about the upper regolith, not whole craters and mountain ranges. That’s more than 100 times faster than previous models that only took micrometeorites into account. Instead of millions of years for those astronaut boot prints and rover tracks to disappear, it now appears that they’ll be wiped clean in just tens of thousands!

October 14, 2016November 5, 2016 by Bob King

We Land on Mars in Just 2 days!

Artist's view of the Schiaparelli lander descending to Mars on October 19. Credit: ESA

Watch how Schiaparelli will land on Mars. Touchdown will occur at 10:48 a.m. EDT (14:48 GMT) Wednesday Oct. 19.

Cross your fingers for good weather on the Red Planet on October 19. That’s the day the European Space Agency’s Schiaparelli lander pops open its parachute, fires nine, liquid-fueled thrusters and descends to the surface of Mars. Assuming fair weather, the lander should settle down safely on the wide-open plains of Meridiani Planum near the Martian equator northwest of NASA’s Opportunity rover. The region is rich in hematite, an iron-rich mineral associated with hot springs here on Earth.

On 19 October 2016, the ExoMars 2016 entry, descent, and landing demonstrator module, known as Schiaparelli, will land on Mars in a region known as Meridiani Planum. The landing sites of the seven rovers and landers that have reached the surface of Mars and successfully operated there are indicated on this map. The background image is a shaded relief map of Mars, based on data from the Mars Orbiter Laser Altimeter (MOLA) instrument, on NASA’s Mars Global Surveyor spacecraft. — On Wednesday, October 19, the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, will land on Mars in Meridiani Planum not far from the Opportunity rover. The map shows the seven rovers and landers that have reached the surface of Mars and successfully operated there. The background image is a shaded relief map of Mars created using data from NASA’s Mars Global Surveyor spacecraft.

The 8-foot-wide probe will be released three days earlier from the Trace Gas Orbiter (TGO) and coast toward Mars before entering its atmosphere at 13,000 mph (21,000 km/hr). During the 6-minute-long descent, Schiaparelli will decelerate gradually using the atmosphere to brake its speed, a technique called aerobraking. Not only is Meridiani Planum flat, it’s low, which means the atmosphere is thick enough to allow Schiaparelli’s heat shield to reduce its speed sufficiently so the chute can be safely deployed. The final firing of its thrusters will ensure a soft and controlled landing.

Artist's impression depicting the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars. Credit: ESA/ATG medialab — Artist’s impression showing Schiaparelli separating from the Trace Gas Orbiter and heading for Mars. The lander is named for late 19th century Italian astronomer **Giovanni Schiaparelli**, who created a detailed telescopic map of Mars. The orbiter will sniff out potentially biological gases such as methane in Mars’ atmosphere and track its sources and seasonal variations. Credit: ESA/ATG medialab

The lander is one-half of the ExoMars 2016 mission, a joint venture between the European Space Agency and Russia’s Roscosmos. The Trace Gas Orbiter (TGO) will fire its thrusters to place itself in orbit about the Red Planet the same day Schiparelli lands. Its job is to inventory the atmosphere in search of organic molecules, methane in particular. Plumes of methane, which may be biological or geological (or both) in origin, have recently been detected at several locations on Mars including Syrtis Major, the planet’s most prominent dark marking. The orbiter will hopefully pinpoint the source(s) as well as study seasonal changes in locations and concentrations.

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, shows what appears to be a dust-covered frozen sea near the Martian equator. It shows a flat plain, part of the Elysium Planitia, that is covered with irregular blocky shapes. They look just like the rafts of fragmented sea ice that lie off the coast of Antarctica on Earth. Raised levels of methane were detected here by ESA's Mars Express orbiter. Copyright: ESA/DLR/FU Berlin (G. Neukum) — This image, taken by ESA’s Express spacecraft, shows what appears to be a dust-covered frozen sea near the Martian equator. Located in Elysium Planitia, the flat plain is covered with irregular blocky shapes. They look just like the rafts of fragmented sea ice that lie off the coast of Antarctica on Earth. Raised levels of methane were detected here by ESA’s Mars Express orbiter. Copyright: ESA/DLR/FU Berlin (G. Neukum)

Methane (CH₄) has long been associated with life here on Earth. More than 90% of the colorless, odorless gas is produced by living organisms, primarily bacteria. Sunlight breaks methane down into other gases over a span of about 300 years. Because the gas relatively short-lived, seeing it on Mars implies an active, current source. There may be several:

Long-extinct bacteria that released methane that became trapped in ice or minerals in the upper crust. Changing temperature and pressure could stress the ice and release that ancient gas into today’s atmosphere.
Bacteria that are actively producing methane to this day.
Abiological sources. Iron can combine with oxygen in terrestrial hot springs and volcanoes to create methane. This gas can also become trapped in solid forms of water or ‘cages’ called clathrate hydrates that can preserve it for a long time. Olivine, a common mineral on Earth and Mars, can react with water under the right conditions to form another mineral called serpentine. When altered by heat, water and pressure, such in environments such as hydrothermal springs, serpentine can produce methane.

Will it turn out to be burping bacteria or mineral processes? Let’s hope TGO can point the way.

This image illustrates possible ways methane might get into Mars’ atmosphere and also be removed from it: microbes (left) under the surface that release the gas into the atmosphere, weathering of rock (right) and stored methane ice called a clathrate. Ultraviolet light can work on surface materials to produce methane as well as break it apart into other molecules (formaldehyde and methanol) to produce carbon dioxide. Credit: NASA/JPL-Caltech/SAM-GSFC/Univ. of Michigan

The Trace Gas Orbiter will also use the Martian atmosphere to slow its speed and trim its orbital loop into a 248-mile-high (400 km) circle suitable for science observations. But don’t expect much in the way of scientific results right away; aerobraking maneuvers will take about a year, so TGO’s job of teasing out atmospheric ingredients won’t begin until December 2017. The study runs for 5 years.

The orbiter will also examine Martian water vapor, nitrogen oxides and other organics with far greater accuracy than any previous probe as well as monitor seasonal changes in the atmosphere’s composition and temperature. And get this — its instruments can map subsurface hydrogen, a key ingredient in both water and methane, down to a depth of a meter (39.4 inches) with greater resolution compared to previous studies. Who knows? We may discover hidden ice deposits or methane sinks that could influence where future rovers will land. Additional missions to Mars are already on the docket, including ExoMars 2020. More about that in a minute.

This artist’s view shows Schiaparelli, the entry, descent and landing demonstrator module, using its thrusters to make a soft landing on Mars on October 19 at 10:48 a.m. EDT (14:48 GMT). Credit: ESA/ATG medialab

While TGO’s mission will require years, the lander is expected to survive for only four Martian days (called ‘sols’) by using the excess energy capacity of its batteries. A set of scientific sensors will measure wind speed and direction, humidity, pressure and electric fields on the surface. A descent camera will take pictures of the landing site on the way down; we’ll should see those photos the very next day. Data and imagery from the lander will be transmitted to ESA’s Mars Express and a NASA Relay Orbiter, then relayed to Earth.

This animation shows the paths of the Trace Gas Orbiter and Schiaparelli lander on Oct. 19 when they arrive at Mars.

If you’re wondering why the lander’s mission is so brief, it’s because Schiaparelli is essentially a test vehicle. Its primary purpose is to test technologies for landing on Mars including the special materials used for protection against the heat of entry, a parachute system, a Doppler radar device for measuring altitude and liquid-fueled braking thrusters.

Martian dust storms can be cause for concern during any landing attempt. Since it’s now autumn in the planet’s northern hemisphere, a time when storms are common, there’s been some finger-nail biting of late. The good news is that storms of recent weeks have calmed and Mars has entered a welcome quiet spell.

To watch events unfold in real time, check out ESA’s live stream channel, Facebook page and Twitter updates. The announcement of the separation of the lander from the orbiter will be made around 11 a.m. Eastern Time (15:00 GMT) Sunday October 16. Live coverage of the Trace Gas Orbiter arrival and Schiaparelli landing on Mars runs from 9-11:15 a.m. Eastern (13:00-15:15 GMT) on Wednesday October 19. Photos taken by Schiaparelli’s descent camera will be available starting at 4 a.m. Eastern (8:00 GMT) on October 20. More details here. We’ll also keep you updated on Universe Today.

The ExoMars 2016 mission will pave the way for a rover mission to the Red Planet in 2020. Credit: ESA

Everything we learn during the current mission will be applied to planning and executing the next — ExoMars 2020, slated to launch in 2020. That venture will send a rover to the surface to search and chemically test for signs of life, present or past. It will collect samples with a drill at various depths and analyze the fines for bio-molecules. Getting down deep is important because the planet’s thin atmosphere lets through harsh UV light from the sun, sterilizing the surface.

Are you ready for adventure? See you on Mars (vicariously)!

October 5, 2016October 6, 2016 by Ken Kremer

First Antares Liftoff in 2 Years Targeted for Dazzling Nighttime Leap from Virginia on Oct. 13

Antares rocket stands erect, reflecting off the calm waters the night before a launch from NASA’s Wallops Flight Facility, VA, on Oct. 28, 2014. Credit: Ken Kremer/kenkremer.com

The first Antares rocket liftoff in nearly two years is now being targeted for Oct. 13 on what is sure to be a dazzling nighttime leap from NASA’s Virginia launch base – and potentially offering a thrilling skyshow to millions of US East Coast spectators, if all goes well.

Top NASA and Orbital ATK managers formally approved the launch of the upgraded commercial Antares rocket for next Thursday evening, Oct. 13, on a cargo resupply mission to the International Space Station (ISS). The announcement follows on the heels of a successful joint pre-launch Flight Readiness Review (FRR).

Blastoff of the Orbital ATK Antares rocket is slated for 9:13 p.m. EDT on Oct. 13 from the Mid-Atlantic Regional Spaceport pad 0A at NASA’s Wallops Flight Facility on Virginia’s picturesque Eastern shore.

Antares will be rolled out to the pad 0A on Oct. 11 – two days prior to the anticipated launch date.

Antares will carry the Orbital OA-5 Cygnus cargo freighter to orbit on a flight bound for the ISS and its multinational crew of astronauts and cosmonauts.

The 14 story tall commercial Antares rocket also will launch for the first time in the upgraded 230 configuration – powered by new Russian-built first stage engines.

For the OA-5 mission, the Cygnus advanced maneuvering spacecraft will be loaded with approximately 2,400 kg (5,290 lbs.) of supplies and science experiments for the International Space Station (ISS).

“Cygnus is loaded with the Saffire II payload and a nanoracks cubesat deployer,” Frank DeMauro, Orbital ATK Cygnus program manager, told Universe Today in a interview.

Among the science payloads aboard the Cygnus OA-5 mission is the Saffire II payload experiment to study combustion behavior in microgravity. Data from this experiment will be downloaded via telemetry. In addition, a NanoRack deployer will release Spire Cubesats used for weather forecasting. These secondary payload operations will be conducted after Cygnus departs the space station.

If Cygnus launches as planned on Oct. 13, it is scheduled to arrive at the station on Sunday, Oct. 16. Astronauts will use the space station’s robotic arm to grapple Cygnus at approximately about 6:45 a.m. EDT and berth it to the bottom of the station’s Unity module.

NASA TV will provide live coverage of the launch as well as the rendezvous and grappling activities.

Pre-launch seaside panorama of Orbital ATK Antares rocket at the NASA's Wallops Flight Facility launch pad. Credit: Ken Kremer - kenkremer.com — Pre-launch seaside panorama of an Orbital ATK Antares rocket at the NASA’s Wallops Flight Facility launch pad. Credit: Ken Kremer – kenkremer.com

The Cygnus spacecraft for the OA-5 mission is named the S.S. Alan G. Poindexter in honor of former astronaut and Naval Aviator Captain Alan Poindexter.

Under the Commercial Resupply Services (CRS) contract with NASA, Orbital ATK will deliver approximately 28,700 kilograms of cargo to the space station. OA-5 is the sixth of these missions.

The 2 year lull in Antares launches followed the rockets immediate grounding after its catastrophic failure just moments after liftoff on Oct. 28, 2014 that doomed the Orb-3 resupply mission to the space station – as witnessed by this author.

First stage propulsion system at base of Orbital Sciences Antares rocket appears to explode moments after blastoff from NASA’s Wallops Flight Facility, VA, on Oct. 28, 2014, at 6:22 p.m. Credit: Ken Kremer – kenkremer.com

Orbital ATK’s Antares commercial rocket had to be overhauled with the completely new RD-181 first stage engines following the destruction of the Antares rocket and Cygnus supply ship two years ago.

The new RD-181 engines are installed on the Orbital ATK Antares first stage core ready to support a full power hot fire test at the NASA Wallops Island launch pad in March 2016. New thrust adapter structures, actuators, and propellant feed lines are incorporated between the engines and core stage. Credit: Ken Kremer/kenkremer.com

In light of the grounding of the SpaceX Falcon 9 and Dragon cargo flights following the catastrophic Sept.1 launch pad disaster, and the catastrophic Antares launch failure in Oct. 2014, this Orbital ATK mission becomes more critical than ever to keep that station stocked and fully operational for the resident crews with a reliable American supply train.

Aerial view of NASA Wallops launch site on Virginia shore shows launch pads for both suborbital and orbital rockets. The Antares rocket Pad 0A for missions to the ISS is in the foreground. Suborbital rockets blast off just behind the Pad 0A water tower. This photo was snapped from on top of Pad 0B that launched NASA‘s LADEE orbiter to the Moon. Credit: Ken Kremer- kenkremer.com

In the meantime, Orbital ATK has successfully resumed launches of their Cygnus cargo freighters to the ISS utilizing the United Launch Alliance (ULA) Atlas V rocket as an interim measure until Antares is returned to flight status

They utilized the ULA Atlas V rocket to successfully deliver two Cygnus vessels to the ISS on the OA-4 flight in Dec 2015 and OA-6 flight in March 2016.

Watch for Ken’s continuing Antares/Cygnus mission and launch reporting. He will be reporting from on site at NASA’s Wallops Flight Facility, VA during the launch campaign.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Aerial view of an Orbital ATK Antares rocket on launch pad at Virginia Space’s Mid-Atlantic Regional Spaceport (MARS) Pad 0A located at NASA's Wallops Flight Facility. Credit: Patrick J. Hendrickson / Highcamera.com — Aerial view of an Orbital ATK Antares rocket on launch pad at Virginia Space’s Mid-Atlantic Regional Spaceport (MARS) Pad 0A located at NASA’s Wallops Flight Facility. Credit: Patrick J. Hendrickson / Highcamera.com

October 4, 2016October 5, 2016 by Ken Kremer

NASA’s First SLS Mars Rocket Fuel Tank Completes Welding

Welding is complete on the largest piece of the core stage that will provide the fuel for the first flight of NASA's new rocket, the Space Launch System, with the Orion spacecraft in 2018. The core stage liquid hydrogen tank has completed welding on the Vertical Assembly Center at NASA's Michoud Assembly Facility in New Orleans. Credit: NASA/MAF/Steven Seipel

The first of the massive fuel tanks that will fly on the maiden launch of NASA’s SLS mega rocket in late 2018 has completed welding at the agency’s rocket manufacturing facility in New Orleans – marking a giant step forward for NASA’s goal of sending astronauts on a ‘Journey to Mars’ in the 2030s.

Technicians have just finished welding together the liquid hydrogen (LH2) fuel tank in the Vertical Assembly Center (VAC) welder at NASA’s Michoud Assembly Facility (MAF) in New Orleans. The VAC is the world’s largest welder.

Welding is nearly complete on the liquid hydrogen tank will provide the fuel for the first flight of NASA's new rocket, the Space Launch System, with the Orion spacecraft in 2018. The tank has now has now completed welding on the Vertical Assembly Center at NASA's Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com — Welding is nearly complete on the liquid hydrogen tank will provide the fuel for the first flight of NASA’s new rocket, the Space Launch System, with the Orion spacecraft in 2018. The tank has now has now completed welding on the Vertical Assembly Center at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com

This flight version of the hydrogen tank is the largest of the two fuel tanks making up the SLS core stage – the other being the liquid oxygen tank (LOX).

In fact the 130 foot tall hydrogen tank is the biggest cryogenic tank ever built for flight.

“Standing more than 130 feet tall, the liquid hydrogen tank is the largest cryogenic fuel tank for a rocket in the world,” according to NASA.

And it is truly huge – measuring also 27.6 feet (8.4 m) in diameter.

The liquid hydrogen tank qualification test article for NASA’s new Space Launch System (SLS) heavy lift rocket lies horizontally after final welding was completed at NASA’s Michoud Assembly Facility in New Orleans in July 2016. Credit: Ken Kremer/kenkremer.com

I recently visited MAF to see this giant tank when it was nearly finished welding in the VAC. I also saw the very first completed test tank version of the hydrogen tank, called the qualification tank which is virtually identical.

The precursor qualification tank was constructed to prove out all the manufacturing techniques and welding tools being utilized at Michoud.

The first liquid hydrogen tank, also called the qualification test article, for NASA's new Space Launch System (SLS) heavy lift rocket lies horizontally beside the Vertical Assembly Center robotic weld machine on July 22, 2016 after final welding was just completed at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com — The first liquid hydrogen tank, also called the qualification test article, for NASA’s new Space Launch System (SLS) heavy lift rocket lies horizontally beside the Vertical Assembly Center robotic weld machine on July 22, 2016 after final welding was just completed at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com

SLS is the most powerful booster the world has even seen and one day soon will propel NASA astronauts in the agency’s Orion crew capsule on exciting missions of exploration to deep space destinations including the Moon, Asteroids and Mars – venturing further out than humans ever have before!

NASA’s agency wide goal is to send humans to Mars by the 2030s with SLS and Orion.

The LH2 and LOX tanks sit on top of one another inside the SLS outer skin. Together the hold over 733,000 gallons of propellant.

The SLS core stage – or first stage – is mostly comprised of the liquid hydrogen and liquid oxygen cryogenic fuel storage tanks which store the rocket propellants at super chilled temperatures. Boeing is the prime contractor for the SLS core stage.

The SLS core stage stands some 212 feet tall.

The SLS core stage is comprised of five major structures: the forward skirt, the liquid oxygen tank (LOX), the intertank, the liquid hydrogen tank (LH2) and the engine section.

The LH2 and LOX tanks feed the cryogenic propellants into the first stage engine propulsion section which is powered by a quartet of RS-25 engines – modified space shuttle main engines (SSMEs) – and a pair of enhanced five segment solid rocket boosters (SRBs) also derived from the shuttles four segment boosters.

NASA engineers successfully conducted a development test of the RS-25 rocket engine Thursday, Aug. 18 at NASA’s Stennis Space Center near Bay St. Louis, Miss. The RS-25 will help power the core stage of the agency’s new Space Launch System (SLS) rocket for the journey to Mars. Credit: Ken Kremer/kenkremer.com

The vehicle’s four RS-25 engines will produce a total of 2 million pounds of thrust.

The tanks are assembled by joining previously manufactured dome, ring and barrel components together in the Vertical Assembly Center by a process known as friction stir welding. The rings connect and provide stiffness between the domes and barrels.

The LH2 tank is the largest major part of the SLS core stage. It holds 537,000 gallons of super chilled liquid hydrogen. It is comprised of 5 barrels, 2 domes, and 2 rings.

The LOX tank holds 196,000 pounds of liquid oxygen. It is assembled from 2 barrels, 2 domes, and 2 rings and measures over 50 feet long.

The maiden test flight of the SLS/Orion is targeted for no later than November 2018 and will be configured in its initial 70-metric-ton (77-ton) Block 1 configuration with a liftoff thrust of 8.4 million pounds – more powerful than NASA’s Saturn V moon landing rocket.

Although the SLS-1 flight in 2018 will be uncrewed, NASA plans to launch astronauts on the SLS-2/EM-2 mission slated for the 2021 to 2023 timeframe.

NASA’s Space Launch System (SLS) blasts off from launch pad 39B at the Kennedy Space Center in this artist rendering showing a view of the liftoff of the Block 1 70-metric-ton (77-ton) crew vehicle configuration. Credit: NASA/MSFC

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

The newly assembled first liquid hydrogen tank, also called the qualification test article, for NASA's new Space Launch System (SLS) heavy lift rocket lies horizontally beside the Vertical Assembly Center robotic weld machine (blue) on July 22, 2016. It was lifted out of the welder (top) after final welding was just completed at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com — The newly assembled first liquid hydrogen tank, also called the qualification test article, for NASA’s new Space Launch System (SLS) heavy lift rocket lies horizontally beside the Vertical Assembly Center robotic weld machine (blue) on July 22, 2016. It was lifted out of the welder (top) after final welding was just completed at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com

September 30, 2016September 30, 2016 by Nancy Atkinson

Journey’s End: Comet Crash for Rosetta Mission Finale

Rosetta’s OSIRIS narrow-angle camera captured this image of Comet 67P/Churyumov-Gerasimenko from an altitude of about 16 km above the surface during the spacecraft’s final descent on September 30, 2016. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA.

With a soft “awwww” from the mission team in the control center in Darmstadt, Germany, the signal from the Rosetta spacecraft faded, indicating the end of its journey. Rosetta made a controlled impact onto Comet 67P/Churyumov–Gerasimenko, sending back incredible close-up images during descent, after two years of investigations at the comet.

“Farewell Rosetta. You have done the job. That was space science at its best,” said Patrick Martin, Rosetta mission manager.

Rosetta’s final resting spot appears to be in a region of active pits in the Ma’at region on the two-lobed, duck-shaped comet.

From #67P with love: a last image, taken 51 metres before #CometLanding #MissionComplete https://t.co/yiSnxDrnba pic.twitter.com/MNuz622tNJ

— ESA Rosetta Mission (@ESA_Rosetta) September 30, 2016

The information collected during the descent – as well as during the entire mission – will be studied for years. So even though the video below about the mission’s end will likely bring a tear to your eye, rest assured the mission will continue as the science from Rosetta is just getting started.

“Rosetta has entered the history books once again,” says Johann-Dietrich Wörner, ESA’s Director General. “Today we celebrate the success of a game-changing mission, one that has surpassed all our dreams and expectations, and one that continues ESA’s legacy of ‘firsts’ at comets.”

Launched in 2004, Rosetta traveled nearly 8 billion kilometers and its journey included three Earth flybys and one at Mars, and two asteroid encounters. It arrived at the comet in August 2014 after being in hibernation for 31 months.

After becoming the first spacecraft to orbit a comet, it deployed the Philae lander in November 2014. Philae sent back data for a few days before succumbing to a power loss after it unfortunately landed in a crevice and its solar panels couldn’t receive sunlight. But Rosetta continued to monitor the comet’s evolution as it made its closest approach and then moved away from the Sun. However, now Rosetta and the comet are too far away from the Sun for the spacecraft to receive enough power to continue operations.

“We’ve operated in the harsh environment of the comet for 786 days, made a number of dramatic flybys close to its surface, survived several unexpected outbursts from the comet, and recovered from two spacecraft ‘safe modes’,” said operations manager Sylvain Lodiot. “The operations in this final phase have challenged us more than ever before, but it’s a fitting end to Rosetta’s incredible adventure to follow its lander down to the comet.”

Compilation of the brightest outbursts seen at Comet 67P/Churyumov–Gerasimenko by Rosetta’s OSIRIS narrow-angle camera and Navigation Camera between July and September 2015. Credit: OSIRIS: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; NavCam: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0.

Rosetta’s Legacy and Discoveries

Of its many discoveries, Rosetta’s close-up views of the curiously-shaped Comet 67P have already changed some long-held ideas about comets. With the discovery of water with a different ‘flavor’ to that of Earth’s oceans, it appears that Earth impacts of comets like 67P/Churyumov–Gerasimenko may not have delivered as much of Earth’s water as previously thought.

From Philae, it was determined that even though organic molecules exist on the comet, they might not be the kind that can deliver the chemical prerequisites for life. However, a later study revealed that complex organic molecules exist in the dust surrounding the comet, such as the amino acid glycine, which is commonly found in proteins, and phosphorus, a key component of DNA and cell membranes. This reinforces the idea that the basic building blocks may have been delivered to Earth from an early bombardment of comets.

Rosetta’s long-term monitoring has also shown just how important the comet’s shape is in influencing its seasons, in moving dust across its surface, and in explaining the variations measured in the density and composition of the comet’s coma.

And because of Rosetta’s proximity to the comet, we all went along for the ride as the spacecraft captured views of what happens as a comet comes close to the Sun, with ice sublimating and dusty jets exploding from the surface.

Studies of the comet show it formed in a very cold region of the protoplanetary nebula when the Solar System was forming more than 4.5 billion years ago. The comet’s two lobes likely formed independently, but came together later in a low-speed collision.

“Just as the Rosetta Stone after which this mission was named was pivotal in understanding ancient language and history, the vast treasure trove of Rosetta spacecraft data is changing our view on how comets and the Solar System formed,” said project scientist Matt Taylor.

Sequence of images captured by Rosetta during its descent to the surface of Comet 67P/C-G on September 30, 2016. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA.

Journey’s End

During the final hours of the mission on Friday morning, the instrument teams watched the data stream in and followed the spacecraft as it moved closer to its targeted touchdown location on the “head” of the 4km-wide comet. The pitted region where Rosetta landed appear to be the places where 67P ejects gas and dust into space, and so Rosetta’s swan song will provide more insight into the comet’s icy jets.

“With the decision to take Rosetta down to the comet’s surface, we boosted the scientific return of the mission through this last, once-in-a-lifetime operation,” said Martin. ““It’s a bittersweet ending, but … Rosetta’s destiny was set a long time ago. But its superb achievements will now remain for posterity and be used by the next generation of young scientists and engineers around the world.”

See more stunning, final images in Bob King’s compilation article, and we bid Rosetta farewell with this lovely poem written by astropoet Stuart Atkinson (used here by permission).

Rosetta’s Last Letter Home

By Stuart Atkinson

And so, my final day dawns.
Just a few grains are left to drain through
The hourglass of my life.
The Comet is a hole in the sky.
Rolling, turning, a black void churning
Silently beneath me.
Down there, waiting for me, Philae sleeps,
Its bed a cold cave floor,
A quilt of sparkling hoarfrost
Pulled over its head…

I have so little time left;
I sense Death flying behind me,
I feel his breath on my back as I look down
At Ma’at, its pits as black as tar,
A skulls’s empty eye sockets staring back
At me, daring me to leave the safety
Of this dusty sky and fly down to join them,
Never to spread my wings again; never
To soar over The Comet’s tortured pinnacles and peaks,
Or play hide and seek in its jets and plumes…

I don’t want to go.
I don’t want to be buried beneath that filthy snow.
This is wrong! I want to fly on!
There is so much more for me to see,
So much more to do –
But the end is coming soon.
All I ask of you is this: don’t let me crash.
Help me land softly, kissing the ground,
Coming to rest with barely a sound
Like a leaf falling from a tree.
Don’t let me die cartwheeling across the plain,
Wings snapping, cameras shattering,
Pieces of me scattering like shrapnel
Across the ice. Let me end my mayfly life
In peace, whole, not as debris rolling uncontrollably
Into Deir el-Medina…

It’s time to go, I know.
Only hours remain until I join Philae
And my great adventure ends
So I’ll send this and say goodbye.
If I dream, I’ll dream of Earth
Turning beneath me, bathing me in
Fifty shades of blue…
In years to come I hope you’ll think of me
And smile, remembering how, for just a while,
We explored a wonderland of ice and dust
Together, hand in hand.

(c) Stuart Atkinson 2016

September 30, 2016September 30, 2016 by Bob King

Rosetta Wows With Amazing Closeups of Comet 67P Before Final ‘Crunchdown’

ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Rosetta fell silent moments after 6:19 a.m. Eastern Time (12:19 UT) this morning, when it gently crashed into 67P/C-G 446 million miles (718 million km) from Earth. As the probe descended to the comet’s bouldery surface of the comet in free fall, it snapped a series of ever-more-detailed photographs while gathering the last bits data on the density and composition of cometary gases, surface temperature and gravity field before the final curtain was drawn.

Let’s take the trip down, shall we?