Illustration of small asteroids passing near Earth. Credit: ESA / P. Carril
Before assuming an asteroid is going to kill us all, take a deep breath and open up the NASA’s Near Earth Object (NEO) program website to check your information, the agency suggests in a statement regarding a so-called threatening asteroid making the rounds in media reports.
Data from the Minor Planet Center shows that the quarter-mile-wide asteroid 2014 UR116 won’t pose a threat to Earth or any other planet in the next 150 years or more, the agency said.
“Some recent press reports have suggested that an asteroid designated 2014 UR116, found on October 27, 2014, at the MASTER-II observatory in Kislovodsk, Russia, represents an impact threat to the Earth,” NASA wrote, assumedly referring to publications such as this one in Russia.
“While this approximately 400-meter sized asteroid has a three-year orbital period around the sun and returns to the Earth’s neighborhood periodically, it does not represent a threat because its orbital path does not pass sufficiently close to the Earth’s orbit … Any statements about risk for impact of discovered asteroids and comets should be verified by scientists and the media by accessing NASA’s Near Earth Object (NEO) program web site.”
Three classes of asteroids that pass near Earth or cross its orbit are named for the first member discovered — Apollo, Aten and Amor. Apollo asteroids like 2014 SC324 routinely cross Earth’s orbit, Atens also cross but have different orbital characteristics and Amors cross Mars’ orbit but miss Earth’s. Credit: ESA
The threat from comets and asteroids hit a fever pitch last year after the Chelyabinsk meteoroid exploded over Russia, injuring thousands and causing property damage (such as blown-out windows). The incident caused NASA, the European Space Agency and others to express a renewed commitment in watching these interluders from Earth.
In the months after the incident, the European Space Agency established an asteroid monitoring center that is intended to be a co-ordination hub for asteroid threats detected in Europe and elsewhere. NASA administrator Charles Bolden also talked about the threat in a Congressional hearing, suggesting measures such as crowdsourcing, co-ordination with other agencies and more telescopic feeds to supplement the monitoring program NASA has right now.
Years ago, Congress directed NASA to find 90% of asteroids 140 meters or larger by 2020, which the agency says is well within reach. Chelyabinsk was only a fraction of that size.
Look high in the southern sky at nightfall to find the familiar giant square that forms part of the body of Pegasus the Flying Horse. The map shows the sky around 6:30 p.m. local time. Source: Stellarium
Cast your gaze up, up, up on the next dark, moonless night and stare into the Great Square of Pegasus. How many stars do you see? Zero? Two? Twenty? If you’d like to find out how dark your sky is, read on.
The Great Square, one of the fall sky’s best known star patterns, rides high in the south at nightfall in mid-December. It forms part of the larger figure of Pegasus the Winged Horse. For our purposes today, we’re going to concentrate on what’s inside the square.
Bounded by Alpheratz (officially belonging to adjacent Andromeda), Scheat, Markab and Algenib, the Great Square is about 15° on a side or one-and-a-half balled fists held at arm’s length.
At first glance, the space appears empty, but a closer look from all but the most light polluted skies will reveal a pair 4th magnitude stars in the upper right quadrant of the square. Fourth magnitude is about the viewing limit from a bright suburban location.
Astronomers use the magnitude scale to measure star and planet brightness. Each magnitude is 2.5 times brighter than the one below it. Aldebaran, which shines at 1st magnitude, is 2.5 times brighter than a 2nd magnitude star, which in turn is 2.5 times brighter than a 3rd magnitude star and so on.
Moonlight and especially light pollution reduce the number of stars we can see in the night sky. This specially prepared map shows slices of sky based on amateur astronomer and author John Bortle’s Dark Sky Scale. Classes range from 1 (excellent with stars fainter than 7th magnitude visible) to 9 (inner city with a limiting magnitude of 4). Click for more detailed descriptions of each class and rate your own sky. Credit: International Dark Sky Association
A first magnitude star is 2.5 x 2.5 x 2.5 x 2.5 x 2.5 (about 100) times brighter than a 6th magnitude star. The bigger the magnitude number, the fainter the star. From cities, you might see 3rd magnitude stars if you can block out stray lighting, but a dark country sky will deliver the Holy Grail naked eye limit of magnitude 6. Skywatchers with utterly dark conditions might glimpse stars as faint 7.5. My own personal best is 6.5.
With each drop in magnitude the number of stars you can see increases exponentially. There are only 22 first magnitude or brighter stars compared to 5,946 stars down to magnitude 6.
What appears blank at first is filled with stars — 26 of them down to magnitude 6.3 are visible inside the Great Square from a dark sky site. How many can you see? Click for a larger version. Source: Stellarium
Ready to stretch your sight and rate your night sky? Step outside at nightfall and allow your eyes to dark-adapt for 20 minutes. With a copy of the map (above) in hand, start with the brightest stars and work your way to the faintest. Each every small step down the magnitude ladder prepares your eyes the next.
With a little effort you should be able to spot the four 4th magnitude range stars. At magnitude 5, you’ll work harder. Moving beyond 5.5 can be very challenging. I revert to averted vision to corral these fainties. Instead of staring directly at the star, play your eye around it. Look a bit to this side and that. This allows a rod-rich part of the retina that’s excellent at seeing faint stuff play through the scene and snatch up the faintest possible stars.
Magnitude scale showing the limits of the eye, binoculars and telescopes. Credit: Dr. Michael Bolte, UCO/Lick Observatory
From my house I can pick out about dozen points of light inside the Square on a moonless night. How many will you see? Once you know your magnitude limit, compare your result to John Bortle’s Dark Sky Scale … and weep. No, just kidding. But his Class 1 excellent sky includes a description of seeing stars down to magnitude 8 and the summer Milky Way casting shadows.
Hard to believe that before about 1790, when gas lighting was introduced in England, Class 1 skies were the norm across virtually the entire planet. Nowadays, most of us have to drive a hundred miles or more to experience true, untrammeled darkness.
Have fun with the challenge and let us know in the comments area how you do. Here’s hoping you find the Great Square far from vacant.
Star trails over Lake Minnewanka in Alberta, Canada. Credit and copyright: Jack-Fusco.
Ready for an adventure? One of our favorite photographers, Jack Fusco, created this stunning travel video for Travel Alberta and viewing it might be enough to make you start packing your bags.
“There’s a certain feeling that you get from standing under a truly dark sky for the first time,” Jack wrote. “Although it’s hard describe the exact feeling of awe that’s felt, it’s an experience that doesn’t leave you. In fact, it’s something that can change you. It can make you forget about sleeping when the sun has set and instead readies you for an adventure. This timelapse is about capturing the adventure of chasing star filled skies and the feeling you get from experiencing it. I hope it inspires people to find their own adventure chasing the stars.”
See some of his beautiful still images from his photo-shoot below:
Chasing Starlight was shot using a Nikon D800E & a Nikon D810 equipped with Nikon 14-24 f/2.8 lenses. See more of Jack’s wonderful work at his website, Instagram, or Jack Fusco Photography.
Aurora over Peyto Lake in Alberta, Canada. Credit and copyright: Jack Fusco.
Earth as viewed from the cabin of the Apollo 11 spacecraft. Credit: NASA
Just how did the Earth — our home and the place where life as we know it evolved — come to be created in the first place? In some fiery furnace atop a great mountain? On some divine forge with the hammer of the gods shaping it out of pure ether? How about from a great ocean known as Chaos, where something was created out of nothing and then filled with all living creatures?
If any of those accounts sound familiar, they are some of the ancient legends that have been handed down through the years that attempt to describe how our world came to be. And interestingly enough, some of these ancient creation stories contain an element of scientific fact to them.
The Mars Reconnaissance Orbiter took this image of a "circular feature" estimated to be 1.2 miles (2 kilometers) in diameter. Picture released in December 2014. Credit: NASA/JPL-Caltech/University of Arizona
NASA is puzzled by this “enigmatic landform” caught on camera by one of its Mars orbiters, but looking around the region provides some possible clues. This 1.2-mile (2-kilometer) feature is surrounded by relatively young lava flows, so they suspect that it could be some kind of volcanism in the Athabasca area that created this rippled surface.
“Perhaps lava has intruded underneath this mound and pushed it up from beneath. It looks as if material is missing from the mound, so it is also possible that there was a significant amount of ice in the mound that was driven out by the heat of the lava,” NASA wrote in an update on Thursday (Dec. 4).
“There are an array of features like this in the region that continue to puzzle scientists. We hope that close inspection of this … image, and others around it, will provide some clues regarding its formation.”
The picture was captured by the Mars Reconnaissance Orbiter’s High Resolution Imaging Science Experiment (HiRISE), a University of Arizona payload which has released a whole slew of intriguing pictures lately. We’ve collected a sample of them below.
These transverse aeolian ridges seen by the Mars Reconnaissance Orbiter are caused by wind, but scientists are unsure why this image (released in December 2014) shows two wavelengths of ripples. Credit: NASA/JPL-Caltech/University of ArizonaThis area south of Coprates Chasma is an example of sulfate and clay deposits on Mars, showing water once flowed readily in this region. Why the water evaporated from the Red Planet is one question scientists are hoping to answer with missions such as the Mars Reconnaissance Orbiter, which took this image (released in December 2014). Credit: NASA/JPL-Caltech/University of ArizonaArabia Terra, one of the dustiest regions on Mars, is filled with dunes such as this one captured by the Mars Reconnaissance Orbiter and released in December 2014. Credit: NASA/JPL/University of Arizona
Time lapse-photo showing geminids over Pendleton, OR. Credit: Thomas W. Earle
Wouldn’t it be nice if a meteor shower peaked on a weekend instead of 3 a.m. Monday morning? Maybe even showed good activity in the evening hours, so we could get our fill and still get to bed at a decent hour. Wait a minute – this year’s Geminids will do exactly that!
Before moonrise this Saturday night December 13th, the Geminids should put on a sweet display. The radiant of the shower lies near the bright pair of stars, Castor and Pollux. Source: Stellarium
What’s more, since the return of this rich and reliable annual meteor shower occurs around 6 a.m. (CST) on Sunday December 14th, both Saturday and Sunday nights will be equally good for meteor watching. After the Perseids took a battering from the Moon last August, the Geminids will provide the best meteor display of 2014. They do anyway! The shower’s been strengthening in recent years and now surpasses every major shower of the year.
The official literature touts a rate of 120 meteors per hour visible from a dark sky site, but I’ve found 60-80 per hour a more realistic expectation. Either way, what’s to complain?
The third quarter Moon rises around midnight Saturday and 1 a.m. on Monday morning. Normally, moonlight would be cause for concern, but unlike many meteor showers the Geminids put on a decent show before midnight. The radiant, the location in the sky from which the meteors will appear to stream, will be well up in the east by 9:30 p.m. local time. That’s a good 2-3 hours of meteor awesomeness before moonrise.
The author takes in this year’s moon-drenched Perseids in comfort.
Shower watching is a total blast because it’s so simple. Your only task is to dress warmly and get comfortable in a reclining chair aware from the unholy glare of unshielded lighting. The rest is looking up. Geminid meteors will flash anywhere in the sky, so picking a direction to watch the shower isn’t critical. I usually face east or southeast for the bonus view of Orion lumbering up from the horizon.
Bring your camera, too. I use a moderately wide angle lens (24-35mm) at f/2.8 (widest setting), set my ISO to 800 or 1600 and make 30-second exposures. The more photos you take, the better chance of capturing a meteor. You can also automate the process by hooking up a relatively inexpensive intervalometer to your camera and have it take the pictures for you.
As you ease back and let the night pass, you’ll see other meteors unrelated to the shower, too. Called sporadics, they trickle in at the rate of 2-5 an hour. You can always tell a Geminid from an interloper because its path traces back to the radiant. Sporadics drop down from any direction.
Captured by an all-sky camera, a Geminid fireball brighter than Venus streaks across the sky above New Mexico on Dec. 14, 2011. Before disintegrating in the atmosphere the meteoroid was about 1/2 inch across. Credit: Marshall Space Flight Center, Meteoroid Environments Office, Bill Cooke
Geminid meteors immolate in Earth’s atmosphere at a moderate speed compared to some showers – 22 miles per second (35 km/sec) – and often flare brightly. Green, red, blue, white and yellow colors have been recorded, making the shower one of the more colorful. Most interesting, the meteoroid stream appears to be sorted according to size with faint, telescopic meteors maxing out a day before the naked eye peak. Larger particles continue to produce unusually bright meteors up to a few days after maximum.
Most meteor showers are the offspring of comets. Dust liberated from vaporizing ice gets pushed back by the pressure of sunlight to form a tail and fans out over the comet’s orbital path. When Earth’s orbit intersects a ribbon of this debris, sand and gravel-sized bits of rock crash into our atmosphere at high speed and burn up in multiple flashes of meteoric light.
Phaethon sprouts a tail (points southeast or to lower left) when close to the Sun in this image taken by NASA’s STEREO Sun-observing spacecraft in 2012. Credit: Credit: Jewitt, Li, Agarwal /NASA/STEREO
But the Geminids are a peculiar lot. Every year in mid-December, Earth crosses not a comet’s path but that of 3200 Phaethon (FAY-eh-thon), a 3.2 mile diameter (5.1 km) asteroid. Phaethon’s elongated orbit brings it scorchingly close (13 million miles) to the Sun every 1.4 years. Normally a quiet, well-behaved asteroid, Phaethon brightened by a factor of two and was caught spewing jets of dustwhen nearest the Sun in 2009, 2010 and 2012. Apparently the intense heat solar heating either fractured the surface or heated rocks to the point of desiccation, creating enough dust to form temporary tails like a comet.
While it looks like an asteroid most of the time, Phaethon may really be a comet that’s still occasionally active. Periodic eruptions provide the fuel for the annual December show.
Most of us will head out Saturday or Sunday night and take in the shower for pure enjoyment, but if you’d like to share your observations and contribute a bit of knowledge to our understanding of the Geminids, consider reporting your meteor sightings to the International Meteor Organization. Here’s the link to get started.
And this just in … Italian astronomer Gianluca Masi will webcast the shower starting at 8 p.m. CST December 13th (2 a.m. UT Dec. 14) on his Virtual Telescope Project site.
The Orion spacecraft floats in the Pacific Ocean after an uncrewed orbital flight test Dec. 5, 2014. In the background is the recovery ship, the USS Anchorage. Credit: NASA
It’s funny to think that your smartphone might be faster than a new spaceship, but that’s what one report is saying about the Orion spacecraft. The computers are less-than-cutting-edge, the processors are 12 years old, and the speed at which it “thinks” is … slow, at least compared to a typical laptop today.
But according to NASA, there’s good reasoning behind using older equipment. In fact, it’s common for the agency to use this philosophy when designing missions — even one such as Orion, which saw the spacecraft soar 3,600 miles (roughly 5,800 kilometers) above Earth in an uncrewed test last week and make the speediest re-entry for a human spacecraft since the Apollo years.
The reason, according to a Computer World report, is to design the spacecraft for reliability and being rugged. Orion — which soared into the radiation-laden Van Allen belts above Earth — needs to withstand that environment and protect humans on board. The computer is therefore based on a well-tested Honeywell system used in 787 jetliners. And Orion in fact carries three computers to provide redundancy if radiation causes a reset.
Up close view of Orion inside the mobile service tower pad 37 at Cape Canaveral Air Force Station in Florida one day prior to launch. Credit: Ken Kremer – kenkremer.com
“The one thing we really like about this computer is that it doesn’t get destroyed by radiation,” said Matt Lemke, NASA’s deputy manager for Orion’s avionics, power and software team, in the report. “It can be upset, but it won’t fail. We’ve done a lot of testing on the different parts of the computer. When it sees radiation, it might have to reset, but it will come back up and work again.”
A 2013 NASA presentation points out that the agency is a common user of commercial off-the-shelf (COTS) electronics. This usually happens for three reasons: officials can’t find military or aerospace alternatives, unknown risks are a part of the mission, or a mission has “a short lifetime or benign space environment exposure”. NASA makes sure to test the electronics beyond design limits and will often make accommodations to make it even safer. Ideally, the use of proven hardware overall reduces risk and cost for a mission, if used properly.
“The more understanding you have of a device’s failure modes and causes, the higher the confidence level that it will perform under mission environments and lifetime,” the presentation says. “Qualification processes are statistical beasts
designed to understand/remove known reliability risks and uncover unknown risks inherent in a part.”
Artist’s conception of NASA’s Space Launch System. Credit: NASA
In fact, the rocket that is eventually supposed to pair up with Orion will also use flight-tested systems for at least the first few flights. The Space Launch System, which NASA hopes will heft Orion on the next test flight in 2017 or 2018, will use solid rocket boosters based on those used with the shuttle. But NASA adds that upgrades are planned to the technology, which flew on shuttle missions in space starting in 1981.
“Although similar to the solid rocket boosters that helped power the space shuttle to orbit, the five-segment SLS boosters include several upgrades and improvements implemented by NASA and ATK engineers,” NASA wrote in a 2012 press release. “In addition, the SLS boosters will be built more affordably and efficiently than shuttle boosters, incorporating new and innovative processes and technologies.”
A handful of other prominent space recycling uses in space exploration:
Venus Express, a European Space Agency mission that uses designs and hardware from the Mars Express and Rosetta missions. It’s finishing its mission soon after eight years in orbit — four times the original plan.
"AstroButch [Butch Wilmore] has set up our Xmas tree in the lab and hung socks for us," tweeted astronaut Samantha Cristoforetti from the International Space Station Dec. 7, 2014. Credit: Samantha Cristoforetti/Twitter
If you think the upside-down Christmas tree above is bizarre — that’s one of the latest activities of Expedition 42 astronauts in space right now — think back to the history of other holidays in orbit.
We’ve seen a vital telescope undergo repairs, an emergency replacement of part of a space station’s cooling system, and even a tree made of food cans. Learn more about these fun holiday times below.
Reading from above the moon (Apollo 8, 1969)
In this famous reading from the Bible, astronauts Frank Borman, Jim Lovell and Bill Anders shared their experience looking at the Moon on Dec. 24, 1968. The Apollo 8 crew was the first to venture to lunar orbit, just seven months before the Apollo 11 crew made it all the way to the surface.
Food can “Christmas tree” (Skylab 4, 1973)
A “Christmas tree” created out of food cans by the Skylab 4 crew in 1973. Credit: NASA
Living on the Skylab station taught astronauts the value of improvisation, such as when the first crew (under NASA’s instructions) repaired a sunshield to stop electronics and people from roasting inside. Skylab 4 took the creativity to Christmas when they created a tree out of food cans.
Hubble Space Telescope repair (STS-103, 1999)
The Hubble Space Telescope during a 1999 repair mission with STS-103 crew members Mike Foale (left, for NASA) and Claude Nicollier (European Space Agency). Credit: NASA
When the Hubble Space Telescope was in hibernation due to a failed gyroscope, the STS-103 crew made repairs in December 1999 that culminated with the final spacewalk on Christmas Day. The telescope remains in great shape to this day, following another repair mission in 2009.
First Christmas on the International Space Station (Expedition 1, 2000)
The Expedition 1 crew with fresh oranges on the International Space Station in December 2000. From left, Yuri Gidzenko (Roscosmos), Bill Shepherd (NASA) and Sergei Krikalev (Roscosmos). Credit: NASA
The Expedition 1 crew was the first on the International Space Station to spend Christmas in orbit. “On this night, we would like to share with all-our good fortune on this space adventure; our wonder and excitement as we gaze on the Earth’s splendor; and our strong sense — that the human spirit to do, to explore, to discover — has no limit,” the crew said in a statement on Christmas Eve, in part.
Ammonia tank replacement (Expedition 38, 2013)
Just last year, an ammonia tank failure crippled a bunch of systems on the International Space Station and forced spacewalkers outside to fix the problem, in the middle of a leaky suit investigation. The astronauts made the final repairs ahead of schedule, on Christmas Eve.
Artist rendition of how the "lake" at Gale Crater on Mars may have looked millions of years ago. Credit and copyright: Kevin Gill.
What is now a mountain, was once a lake. That’s the conclusion of the Curiosity Mars rover science team after studying data and imagery from the rover, which indicates that the mountain the rover is now climbing in Gale Crater – Aeolis Mons, or Mount Sharp — was built by sediments deposited in a large lake bed over tens of millions of years.
“Gale Crater had a large lake at the bottom — perhaps even a series of lakes,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program during a press briefing on Monday, “that may have been big enough to last millions of years.”
This evenly layered rock photographed by the Mast Camera (Mastcam) on NASA’s Curiosity Mars Rover on Aug. 7, 2014, shows a pattern typical of a lake-floor sedimentary deposit not far from where flowing water entered a lake. Credit: NASA/JPL-Caltech/MSSS.
This isn’t the first time that the Mars Science Laboratory team has made the conclusion that a lake once existed in Gale Crater, or even that the water was long-lived. A year ago, the team said that an ancient fresh water lake at the Yellowknife Bay area near Curiosity’s landing site once existed for periods spanning perhaps millions to tens of millions of years in length – before eventually evaporating completely after Mars lost its thicker atmosphere.
But now, the team has garnered a bigger picture of Gale Crater, and they suggest that water could have covered nearly the entirety of the 154-kilometer-wide crater around 3.5 billion years ago, and that the 5-kilometer-high mountain that now towers over the crater could have been formed by repeated cycles of sediment buildup and erosion.
“If our hypothesis for Mount Sharp holds up, it challenges the notion that warm and wet conditions were transient, local, or only underground on Mars,” said Ashwin Vasavada, Curiosity deputy project scientist. “A more radical explanation is that Mars’ ancient, thicker atmosphere raised temperatures above freezing globally, but so far we don’t know how the atmosphere did that.”
By continuing the study of this crater, Vasavada said, the team is “more sure than ever that we’re going to learn about the early history of Mars, it’s changing climate, and the potential for Mars to support life.”
A few months ago, when Curiosity was still a few kilometers away from the base of Aeolis Mons, the science team started noticing distinct patterns on the rocks from images taken by the rover. There were tilted beds of sandstone all facing south in the direction of the mountain. The planetary geologists concluded that these tilted beds of sandstone formed where streams emptied into standing bodies of water, probably lakes.
This diagram depicts rivers feeding into a lake. Where the river enters the water body, the water’s flow decelerates, sediments drop out, and a delta forms, depositing a prism of sediment that tapers out toward the lake’s interior. Progressive build-out of the delta through time leads to formation of sediments that are inclined in the direction toward the lake body. Credit: NASA/JPL-Caltech/MSSS/Imperial College.
Sediments carried by flowing water sink when they enter a body of water, forming a sloped wall that slowly advances forward as sediment continues to fall.
In September of this year, when Curiosity arrived at the rocks that form the base of Aeolis Mons at a region the team calls “Kimberley,” they saw a new type of rock, one that forms when tiny particles of sediment slowly settle out within a lake, forming mud at the lake bottom. These ‘mudstones’ are very finely layered, suggesting that the river and lake system was going through cycles of change.
“Layered sandstone or pebble beds at the Kimberley record a build-out or accretion of sediment from north to south,” said Curiosity science team member Sanjeev Gupta, “ and that build-out of inclined beds strongly suggests rivers depositing sediment into a standing body of water.”
This image from Curiosity’s Mastcam shows inclined beds of sandstone interpreted as the deposits of small deltas fed by rivers flowing down from the Gale Crater rim and building out into a lake where Mount Sharp is now. It was taken March 13, 2014, just north of the “Kimberley” waypoint. Credit: NASA/JPL-Caltech/MSSS
Over a span of perhaps millions of years, water flowed from the northern rim of Gale Crater toward the center, bringing sediment that slowly formed the lower layers of Mount Sharp.
After the crater filled to a height of at least a few hundred yards and the sediments hardened into rock, the accumulated layers of sediment were sculpted over time into a mountainous shape by wind erosion that carved away the material between the crater perimeter and what is now the edge of the mountain.
While this is definitely not the first time that evidence of water has been discovered on Mars — evidence from several Mars missions point to wet environments on ancient Mars – scientist have yet to put together a model of Mars’ ancient climate that could have produced long periods warm enough for stable water on the surface.
This illustration depicts a lake of water partially filling Mars’ Gale Crater, receiving runoff from snow melting on the crater’s northern rim. Image Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
But this latest finding suggests Mars may have maintained a climate that could have produced long-lasting lakes at many locations on the Red Planet, which leads to potentially long-lasting habitable environments.
To learn more about this intriguing region on Mars, over the next few months the Curiosity rover will continue to climb up the lower layers of Aeolis Mons to see if the hypothesis for how it formed holds up. The team will also look at the chemistry of the rocks to see if the water that was once present would’ve been of the kind that could support microbial life.
“With only 30 vertical feet of the mountain behind us, we’re sure there’s a lot more to discover,” said Vasavada.
A mosaic of Comet 67P/Churyumov-Gerasimenko taken Dec. 2 with the Rosetta spacecraft. The shadowed area is a crater in which Philae is expected to be. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
Don’t forget about Philae! The comet lander made a touchdown a month ago this week on its target, marking the first time we’ve ever made a soft landing on such a body. Celebrations were quickly mixed with confusion, however, as controllers realized the spacecraft drifted quite a ways off target. In fact, we still don’t know exactly where it is.
The parent Rosetta spacecraft is working well in orbit and still transmitting images of the comet while Philae hibernates in a shady spot below. This latest image here shows a clear view of where the European Space Agency thinks the lander arrived — somewhere in the rim of that shadowy crater you see up front.
“The internal walls are seen in quite some detail. It is thought that Philae’s final touchdown site might be located close to the rim of this depression, but further high-resolution imaging is still being obtained and analyzed to confirm this,” the agency wrote in a statement concerning the image of Comet 67P/Churyumov-Gerasimenko.
This is based on data collected from Philae in a brief science surge on the surface. Recently, information based on measured magnetic fields showed the spacecraft likely hit an object — perhaps a crater rim — as it drifted for two hours on the surface, unsecured by the harpoons that were supposed to fire to hold it in place.
The distortion at bottom of this Dec. 1, 2014 mosaic of Comet 67P/Churyumov-Gerasimenko occured as imagers made image joining adjustments for the comet’s rotation and the movements of the Rosetta spacecraft. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
Searches for the lander are ongoing, but it’s hard to pick it out on such a boulder-strewn landscape. Yet the agency is doing its mightiest, and has made some progress on the problem since the landing took place. Rosetta caught several glimpses of the lander during its journey across the surface. And they have data from an experiment that communicated between Rosetta and Philae which could help pinpoint the location.
Rosetta science results have been quiet in the past week, although ESA has released several images of the comet. This comes as the agency has been criticized for its data release policy regarding the mission. It’s a vigorous debate, with there being examples of more open missions (such as Curiosity) and more closed missions (such as the Hubble Space Telescope) to compare Rosetta’s releases with.
As these activities continue, however, Rosetta will remain transmitting information from 67P through at least part of 2015, watching the comet increase in activity as both draw closer to the Sun. Jets and gas are visible already in some of the recent images of the comet, which you can see below.
Comet 67P/Churyumov-Gerasimenko viewed by the Rosetta spacecraft on Nov. 30, 2014 showing off layered material in the “neck” of the comet. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0Erupting gas and dust is just visible in the “neck” region of Comet 67P/Churyumov-Gerasimenko in this montage taken Nov. 26, 2014 by the Rosetta spacecraft. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0Gas and dust stream from Comet 67P/Churyumov–Gerasimenko in this mosaic from the Rosetta spacecraft taken Nov. 20, 2014. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
