Don’t take these spectacular Mercury images (below the jump) for granted. Three weeks ago, NASA’s orbiting Mercury spacecraft did an engine fire to boost its altitude above the hothouse planet. Another one is scheduled for January.
But all this will do is delay the end of the long-running mission — the first one to orbit Mercury — until early 2015, the Johns Hopkins Applied Physics Laboratory wrote in an update. These maneuvers “extend orbital operations and delay the probe’s inevitable impact onto Mercury’s surface until early next spring,” the organization said in a statement.
Until MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) flew by Mercury for the first time in January 2008, we knew very little about the planet. The only close-up pictures previously came from Mariner 10, which whizzed by a few times in 1974-75. After a few flybys, MESSENGER settled into orbit in 2011.
Mercury’s high density compared to other planets remains a mystery. MESSENGER investigations found a surface that didn’t have a lot of iron in it, but lots of volatile materials such as sodium and sulfur.
The surface had volcanoes on it and still has water ice in permanently shadowed craters near the poles.
Its magnetic field produces weird effects that are still being examined. NASA speaks of “unexplained bursts of electrons and highly variable distributions of different elements” in its tenuous atmosphere, called an exosphere.
“Our only regret is that we have insufficient propellant to operate another 10 years, but we look forward to the incredible science returns planned for the final eight months of the mission,” stated Andy Calloway, MESSENGER mission operations manager at the Johns Hopkins University Applied Physics Laboratory, at the time.
MESSENGER has done several orbital-boosting maneuvers in recent months to prolong the mission as possible. The first one in June adjusted its orbit to between 71.4 miles (115 kilometers) and 97.2 miles (156.4 kilometers), while the second in September went lower: a minimum of 15.7 miles (25.2 kilometers) to 58.2 miles (93.7 kilometers).
As of late October, MESSENGER’s minimum altitude was 115.1 miles (185.2 miles) and it took roughly eight hours for it to orbit Mercury. Once it finally crashes, Europe’s and Japan’s BepiColombo is expected to be the next Mercury orbiting mission. It launches in 2016, but will take several flybys past planets to get there and won’t arrive until 2024.
At T MINUS 1 Week on this Thanksgiving Holiday, all launch processing events remain on track for the first blast off of NASA’s new Orion crew vehicle on Dec. 4, 2014 which marks the first step on the long road towards sending Humans to Mars in the 2030s.
Orion will lift off on a United Launch Alliance Delta IV Heavy rocket on its inaugural test flight to space on the uncrewed Exploration Flight Test-1 (EFT-1) mission at 7:05 a.m. EST on December 4, 2014 from Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida.
Technicians and engineers installed Orion’s batteries and have been conducting a thorough checkout of all the electrical and battery connections between the crew module, service module and Delta IV Heavy second stage while working inside the mobile service tower at pad 37.
There is some margin time available in the schedule in case additional testing and checkouts are required.
Orion’s launch window opens at 7:05 a.m. EST on Dec. 4 at the beginning of a launch window that extends 2 hours, 39 minutes.
One week ago, top NASA and Lockheed Martin managers gave the “GO” to continue with launch preparations after the vehicle passed the Flight Readiness Review (FRR) on Thursday, Nov. 20.
This past week the doors of the Mobile Servicing Tower (MST) at pad 37 were opened to reveal the Orion spacecraft stack atop the Delta IV Heavy that will carry the spacecraft into orbit.
The Delta IV Heavy is the world’s most powerful rocket.
The MST will be rolled back from the rocket stack on Wednesday evening, Dec. 3 starting 8 hours, 15 minutes before launch to allow the rocket to be fueled and continue into the final stage of launch operations and the countdown to liftoff on Thursday morning Dec. 4.
I’ll be at the pad during MST rollback reporting live for Universe Today.
The two-orbit, four and a half hour Orion EFT-1 flight around Earth will lift the Orion spacecraft and its attached second stage to an orbital altitude of 3,600 miles, about 15 times higher than the International Space Station (ISS) – and farther than any human spacecraft has journeyed in 40 years.
Orion is NASA’s next generation human rated vehicle that will carry America’s astronauts beyond Earth on voyages venturing farther into deep space than ever before – beyond the Moon to Asteroids, Mars and other destinations in our Solar System.
Watch for Ken’s ongoing Orion coverage and he’ll be onsite at KSC in the days leading up to the historic launch on Dec. 4.
Stay tuned here for Ken’s continuing Orion and Earth and planetary science and human spaceflight news.
It’s a well-known fact that Earth’s ozone layer protects us from a great deal of the Sun’s ultra-violet radiation. Were it not for this protective barrier around our planet, chances are our surface would be similar to the rugged and lifeless landscape we observe on Mars.
Beyond this barrier lies another – a series of shields formed by a layer of energetic charged particles that are held in place by the Earth’s magnetic field. Known as the Van Allen radiation belts, this wall prevents the fastest, most energetic electrons from reaching Earth.
And according to new research from NASA’s Van Allen probes, it now appears that these belts may be nearly impenetrable, a finding which could have serious implications for future space exploration and research.
The existence of a belt of charged particles trapped by the Earth’s magnetosphere has been the subject of research since the early 20th century. However, it was not until 1958 that the Explorer 1 and Explorer 3 spacecrafts confirmed the existence of the belt, which would then be mapped out by the Explorer 4, Pioneer 3, and Luna 1 missions.
Since that time, scientists have discovered much about this belt, including how it interacts with other fields around our planet to form a nearly-impenetrable barrier to incoming electrons.
This discovery was made using NASA’s Van Allen Probes, launched in August 2012 to study the region. According to the observations made by the probes, this region can wax and wane in response to incoming energy from the sun, sometimes swelling up enough to expose satellites in low-Earth orbit to damaging radiation.
“This barrier for the ultra-fast electrons is a remarkable feature of the belts,” said Dan Baker, a space scientist at the University of Colorado in Boulder and first author of the paper. “We’re able to study it for the first time, because we never had such accurate measurements of these high-energy electrons before.”
Understanding what gives the radiation belts their shape and what can affect the way they swell or shrink helps scientists predict the onset of those changes. Such predictions can help scientists protect satellites in the area from the radiation.
In the decades since they were first discovered, scientists have learned that the size of the two belts can change – or merge, or even separate into three belts occasionally. But generally the inner belt stretches from 644 km to 10,000 km (400 – 6,000 mi) above the Earth’s surface while the outer belt stretches from 13,500 t0 58,000 km (8,400 – 36,000 mi).
Up until now, scientists have wondered why these two these belts have existed separately. Why, they have wondered, is there a fairly empty space between the two that appears to be free of electrons? That is where the newly discovered barrier comes in.
The Van Allen Probes data showed that the inner edge of the outer belt is, in fact, highly pronounced. For the fastest, highest-energy electrons, this edge is a sharp boundary that, under normal circumstances, cannot be penetrated.
“When you look at really energetic electrons, they can only come to within a certain distance from Earth,” said Shri Kanekal, the deputy mission scientist for the Van Allen Probes at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and a co-author on the Nature paper. “This is completely new. We certainly didn’t expect that.”
The team looked at possible causes. They determined that human-generated transmissions were not the cause of the barrier. They also looked at physical causes, asking if the shape of the Earth’s magnetic field could be the cause of the boundary. However, NASA scientists studied and eliminated that possibility and determined that the presence of other space particles appears to be the more likely cause.
The radiation belts are not the only particle structures surrounding Earth. A giant cloud of relatively cool, charged particles called the plasmasphere fills the outermost region of Earth’s atmosphere, beginning at about 600 miles up and extending partially into the outer Van Allen belt. The particles at the outer boundary of the plasmasphere cause particles in the outer radiation belt to scatter, removing them from the belt.
This scattering effect is fairly weak and might not be enough to keep the electrons at the boundary in place, except for a quirk of geometry – the radiation belt electrons move incredibly quickly, but not toward Earth. Instead, they move in giant loops around Earth.
The Van Allen Probes’ data show that in the direction toward Earth, the most energetic electrons have very little motion at all – just a gentle, slow drift that occurs over the course of months. This movement is so slow and weak that it can be rebuffed by the scattering caused by the plasmasphere.
This also helps explain why – under extreme conditions, when an especially strong solar wind or a giant solar eruption such as a coronal mass ejection sends clouds of material into near-Earth space – the electrons from the outer belt can be pushed into the usually-empty slot region between the belts.
“The scattering due to the plasmapause is strong enough to create a wall at the inner edge of the outer Van Allen Belt,” said Baker. “But a strong solar wind event causes the plasmasphere boundary to move inward.”
A massive inflow of matter from the sun can erode the outer plasmasphere, moving its boundaries inward and allowing electrons from the radiation belts the room to move further inward too.
The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, built and operates the Van Allen Probes for NASA’s Science Mission Directorate. The mission is the second in NASA’s Living With a Star program, managed by Goddard.
A paper on these results appeared in the Nov. 26, 2014, issue of Nature magazine. And be sure to watch this animated video produced by the Goddard Space Center that explains the Van Allen belt in brief:
Feeling lucky? Events such as the Comet Siding Spring approach by Mars in October only happen about once every eight million years, according to NASA.
And after we were treated to spectacular views from the agency’s spacecraft (see Curiosity and Opportunity and MAVEN, for example), we now have fresh pictures this month from an Indian mission. Also, NASA has released science results suggesting that the chemistry of Mars’ atmosphere could be changed forever from the close encounter.
“The image in the center shows a streak … radiating out of the comet’s nucleus (out of frame), possibly indicating the jet from [the] comet’s nucleus,” the Indian Science Research Organisation wrote of the above image sequence on its Facebook mission page.
“Usually jets represent outgassing activity from [the] vents of the comet-nucleus, releasing dust and ice crystals. The outgassing activity gradually increases as the comet moves closer to the Sun.”
The comet’s dust likely produced a meteor shower or meteor storm when particles from it crashed into the upper atmosphere, which “literally changed the chemistry,” added Jim Green, director of NASA’s planetary science division, in a recent discussion highlighted on an agency blog.
The agency says the dust created vaporized metals, which will eventually transform to dust or “meteoric smoke.” MAVEN (which stands for Mars Atmosphere and Volatile EvolutioN) will be monitoring the long-term effects. Possible results include high-altitude clouds or at the most extreme, maybe permanently altering what the chemistry of the atmosphere is. Not a bad thing for a mission to study shortly after it arrived at Mars.
You can view more science results from NASA’s studies of Siding Spring in this recent Universe Today story from Bob King, which talks in more detail about the meteor shower, new layers in the Mars atmosphere and the omnipresent dust.
As Americans get ready for turkey feasts and other Thanksgiving goodies today, let’s take a few moments to think about the crew of six people on board the International Space Station. Two Americans, a European and three Russians are working there now and will be taking most of today (Nov. 26) off for the holiday.
What the heck will they eat? The NASA interview above provides some clues, including a surprise about leftovers. More details below the jump.
NASA, which is responsible for supplying the three astronauts using the American segment of the space station, generally allocates four pounds of food per crew member per day (including packaging), according to Vickie Kloeris, food system manager for the station. Astronauts can also bring a little bit of bonus food with them for special treats. The food isn’t sent up as meal plans, but as different kinds (meats, vegetables, and the like) that the astronauts can assemble at will.
“We don’t have a set-aside meal for Thanksgiving. but they do have all these products available to choose from,” Kloeris said in the interview. “Crew members do know that they’re going to be on orbit during the holidays, [so] they often put special items in their bonus containers with the holidays in mind.”
Kloreis said she couldn’t reveal what Expedition 42 has in its grab boxes, but in the past astronauts have brought up items such as cranberry sauce or icing/frosting to put on cookies in orbit.
Below you can see a recent tweet from former Canadian astronaut Chris Hadfield concerning a typical meal for astronauts, which he put up with a Thanksgiving reference. Whatever the crew is having up there, we wish them a Happy Thanksgiving!
Dreams of space are often tied to jet engines or solar sails or taking a ride on a rocketship. But it’s often quite efficient to do research from Earth, especially from the high reaches of the atmosphere where there are few molecules to get in the way of observations.
NASA wants to do more of this kind of astronomy with an airship — but at an extreme height of 65,000 feet (20 kilometers) for 20 hours. No powered-airship mission has managed to last past eight hours at this height because of the winds in that zone, but NASA is hoping that potential creators would be up to the challenge.
This isn’t a guaranteed mission yet. NASA has a solicitation out right now to gauge interest from the community, and to figure out if it is technically feasible. This program would be a follow-on to ideas such as SOFIA, a flying stratospheric telescope that the agency plans to defund in future budgets.
Their goal is to fly an airship with a 44-pound (20-kilogram) payload at this altitude for 20 hours. If a company is feeling especially able, it can even try for a more difficult goal: a 440-pound (200-kilogram) payload for 200 hours.
“We are seeking to take astronomy and Earth science to new heights by enabling a long-duration, suborbital platform for these kinds of research,” stated lead researcher Jason Rhodes, an astrophysicist at NASA’s Jet Propulsion Laboratory in California.
And why not just use a balloon? It comes down to communications, NASA says: “Unlike a balloon, which travels with air currents, airships can stay in one spot,” the agency states. “The stationary nature of airships allows them to have better downlink capabilities, because there is always a line-of-sight communication.”
Here’s the 22nd-century version of breaking the surly bonds of Earth: NASA and private company Made In Space have just collaborated on the first 3-D printed part in space, ever.
The milestone yesterday (Nov. 25) is a baby step towards off-Earth manufacturing, but the implications are huge. If these testbeds prove effective enough, eventually we can think of creating these parts in other destinations such as the Moon, or an asteroid, or even Mars.
“We look at the operation of the 3-D printer as a transformative moment, not just for space development, but for the capability of our species to live away from Earth,” stated Aaron Kemmer, CEO of Made In Space — the company that developed the printer.
There are still kinks to be worked out, however. The “part adhesion” on the tray after the piece was created had a bond that was mightier than controllers anticipated, which could mean that bonding is different in microgravity. A second calibration coupon should be created shortly as controllers make adjustments to the process.
We’ll see several of these “test coupons” manufactured in the next few months and then sent back to Earth for more detailed analysis. Meanwhile, we have two more 3-D printers to look forward to in space: one created by the Italians that should arrive while their citizen, Samantha Cristoforetti, is still on station (she just arrived a few days ago) and a second one created by Made In Space that is supposed to commercialize the process.
The idea of 3-D printing has been discussed extensively in the media by both NASA and the European Space Agency in the past year or so. ESA has released media speculating on how additive manufacturing could be used to create Moon bases at some distant date. Meanwhile, NASA has talked about perhaps creating food using a 3-D printer.
If additive manufacturing takes off, so to speak, it could reduce shipping costs from Earth to the International Space Station because controllers could just send up a set of instructions to replace a part or tool. But NASA should move quickly to test this stuff out, according to a recent National Research Council report; the station is approved for operations only until 2020 (so far), which leaves only about five years or so to do testing before agencies possibly move to other destinations.
If too close to an environment harboring complex life, a gamma ray burst could spell doom for that life. But could GRBs be the reason we haven’t yet found evidence of other civilizations in the cosmos? To help answer the big question of “where is everybody?” physicists from Spain and Israel have narrowed the time period and the regions of space in which complex life could persist with a low risk of extinction by a GRB.
GRBs are some of the most cataclysmic events in the Universe. Astrophysicists are astounded by their intensity, some of which can outshine the whole Universe for brief moments. So far, they have remained incredible far-off events. But in a new paper, physicists have weighed how GRBs could limit where and when life could persist and evolve, potentially into intelligent life.
In their paper, “On the role of GRBs on life extinctions in the Universe”, published in the journal Science, Dr. Piran from Hebrew University and Dr. Jimenez from University of Barcelona consider first what is known about gamma ray bursts. The metallicity of stars and galaxies as a whole are directly related to the frequency of GRBs. Metallicity is the abundance of elements beyond hydrogen and helium in the content of stars or whole galaxies. More metals reduce the frequency of GRBs. Galaxies that have a low metal content are prone to a higher frequency of GRBs. The researchers, referencing their previous work, state that observational data has shown that GRBs are not generally related to a galaxy’s star formation rate; forming stars, including massive ones is not the most significant factor for increased frequency of GRBs.
As fate would have it, we live in a high metal content galaxy – the Milky Way. Piran and Jimenez show that the frequency of GRBs in the Milky Way is lower based on the latest data available. That is the good news. More significant is the placement of a solar system within the Milky Way or any galaxy.
The paper states that there is a 50% chance of a lethal GRB’s having occurred near Earth within the last 500 million years. If a stellar system is within 13,000 light years (4 kilo-parsecs) of the galactic center, the odds rise to 95%. Effectively, this makes the densest regions of all galaxies too prone to GRBs to permit complex life to persist.
The Earth lies at 8.3 kilo-parsecs (27,000 light years) from the galactic center and the astrophysicists’ work also concludes that the chances of a lethal GRB in a 500 million year span does not drop below 50% until beyond 10 kilo-parsecs (32,000 light years). So Earth’s odds have not been most favorable, but obviously adequate. Star systems further out from the center are safer places for life to progress and evolve. Only the outlying low star density regions of large galaxies keep life out of harm’s way of gamma ray bursts.
The paper continues by describing their assessment of the effect of GRBs throughout the Universe. They state that only approximately 10% of galaxies have environments conducive to life when GRB events are a concern. Based on previous work and new data, galaxies (their stars) had to reach a metallicity content of 30% of the Sun’s, and the galaxies needed to be at least 4 kilo-parsecs (13,000 light years) in diameter to lower the risk of lethal GRBs. Simple life could survive repeated GRBs. Evolving to higher life forms would be repeatedly set back by mass extinctions.
Piran’s and Jimenez’s work also reveals a relation to a cosmological constant. Further back in time, metallicity within stars was lower. Only after generations of star formation – billions of years – have heavier elements built up within galaxies. They conclude that complex life such as on Earth – from jelly fish to humans – could not have developed in the early Universe before Z > 0.5, a cosmological red-shift equal to ~5 billion years ago or longer ago. Analysis also shows that there is a 95% chance that Earth experienced a lethal GRB within the last 5 billion years.
The question of what effect a nearby GRB could have on life has been raised for decades. In 1974, Dr. Malvin Ruderman of Columbia University considered the consequences of a nearby supernova on the ozone layer of the Earth and on terrestrial life. His and subsequent work has determined that cosmic rays would lead to the depletion of the ozone layer, a doubling of the solar ultraviolet radiation reaching the surface, cooling of the Earth’s climate, and an increase in NOx and rainout that effects biological systems. Not a pretty picture. The loss of the ozone layer would lead to a domino effect of atmospheric changes and radiation exposure leading to the collapse of ecosystems. A GRB is considered the most likely cause of the mass extinction at the end of the Ordovician period, 450 million years ago; there remains considerable debate on the causes of this and several other mass extinction events in Earth’s history.
The paper focuses on what are deemed long GRBs – lGRBs – lasting several seconds in contrast to short GRBs which last only a second or less. Long GRBs are believed to be due to the collapse of massive stars such as seen in supernovas, while sGRBs are from the collision of neutron stars or black holes. There remains uncertainty as to the causes, but the longer GRBs release far greater amounts of energy and are most dangerous to ecosystems harboring complex life.
The paper narrows the time and space available for complex life to develop within our Universe. Over the age of the Universe, approximately 14 billion years, only the last 5 billion years have been conducive to the creation of complex life. Furthermore, only 10% of the galaxies within the last 5 billion years provided such environments. And within only larger galaxies, only the outlying areas provided the safe distances needed to evade lethal exposure to a gamma ray burst.
This work reveals how well our Solar System fits within the ideal conditions for permitting complex life to develop. We stand at a fairly good distance from the Milky Way’s galactic center. The age of our Solar System, at approximately 4.6 billion years, lies within the 5 billion year safe zone in time. However, for many other stellar systems, despite how many are now considered to exist throughout the Universe – 100s of billions in the Milky Way, trillions throughout the Universe – simple is probably a way of life due to GRBs. This work indicates that complex life, including intelligent life, is likely less common when just taking the effect of gamma ray bursts into consideration.
And even as the rover works through aging problems, the science team is still able to push it further — it just crested 41 kilometers (25.48 miles) on Sol Sol 3,836 (around Nov. 9)! Check out some recent pictures from the rover below.
The NASA machine is roaming the west edge of Endeavour Crater on its way to an area nicknamed “Marathon Valley”, which could contain clay minerals. Clays are considered a sign of water being in a region in the ancient past, which feeds into NASA’s ongoing search for habitable environments on Mars.
By the way, Opportunity is now just shy of a marathon’s worth of driving on Mars (which would be 26 miles, or 41.8 kilometers). In the meantime, we’ve collected some raw images from Opportunity to share. What new horizons will the plucky rover find next, as it draws close to its 11th anniversary on Mars in January?
As the space community counts down the days to the long-awaited Dec. 4 uncrewed launch of the Orion spacecraft — that vehicle that is supposed to bring astronauts into the solar system in the next decade — NASA is already thinking ahead to the next space test in 2017 or 2018.
Riding atop the new Space Launch System rocket, if all goes to plan, will be a suite of CubeSats that will explore the Moon as Orion makes its journey out to our largest closest celestial neighbor. NASA announced details of the $5 million “Cube Quest” challenge yesterday (Nov. 24).
CubeSats are tiny satellites that are so small that they are often within the reach of universities and similar institutions that want to perform science in space without the associated cost of operating a huge mission. The concept has been so successful that some companies are basing their entire business model on it, such as Planet Labs — a company that is performing Earth observations with the small machines.
The competition will be divided into several parts, including a ground tournament to see if the CubeSats can fly on the SLS, a lunar derby to ensure they can communicate at a distance of 10 times the Earth-moon distance, and a deep-space derby to put the CubeSat in a “stable lunar orbit” and work well there.
“The Cube Quest Challenge seeks to develop and test subsystems necessary to perform deep space exploration using small spacecraft. Advancements in small spacecraft capabilities will provide benefits to future missions and also may enable entirely new mission scenarios, including future investigations of near-Earth asteroids,” NASA stated.