An artist's image of an asteroid Impact. Image Credit: University of California Observatories/Don Davis.
All over the Earth, there is a buried layer of sediment rich in iridium called the Cretaceous Paleogene-Boundary (K-Pg.) This sediment is the global signature of the 10-km-diameter asteroid that killed off the dinosaurs—and about 50% of all other species—66 million years ago. Now, in an effort to understand how life recovered after that event, scientists are going to drill down into the site where the asteroid struck—the Chicxulub Crater off the coast of Mexico’s Yucatan Peninsula.
The end-Cretaceous extinction was a global catastrophe, and a lot is already known about it. We’ve learned a lot about the physical effects of the strike on the impact area from oil and gas drilling in the Gulf of Mexico. According to data from that drilling, released on February 5th in the Journal of Geophysical Research: Solid Earth, the asteroid that struck Earth displaced approximately 200,000 cubic km (48,000 cubic miles) of sediment. That’s enough to fill the largest of the Great Lakes—Lake Superior—17 times.
The Chicxulub impact caused earthquakes and tsunamis that first loosened debris, then swept it from nearby areas like present-day Florida and Texas into the Gulf basin itself. This layer is hundreds of meters thick, and is hundreds of kilometers wide. It covers not only the Gulf of Mexico, but also the Caribbean and the Yucatan Peninsula.
In April, a team of scientists from the University of Texas and the National University of Mexico will spend two months drilling in the area, to gain insight into how life recovered after the impact event. Research Professor Sean Gulick of the University of Texas Institute for Geophysics told CNN in an interview that the team already has a hypothesis for what they will find. “We expect to see a period of no life initially, and then life returning and getting more diverse through time.”
Scientists have been wanting to drill in the impact region for some time, but couldn’t because of commercial drilling activity. Allowing this team to study the region directly will build on what is already known: that this enormous deposit of sediment happened over a very short period of time, possibly only a matter of days. The drilling will also help paint a picture of how life recovered by looking at the types of fossils that appear. Some scientists think that the asteroid impact would have lowered the pH of the oceans, so the fossilized remains of animals that can endure greater acidity would be of particular interest.
The Chicxulub impact was a monumental event in the history of the Earth, and it was extremely powerful. It may have been a billion times more powerful than the atomic bomb dropped on Hiroshima. Other than the layer of sediment laid down near the site of the impact itself, its global effects probably included widespread forest fires, global cooling from debris in the atmosphere, and then a period of high temperatures caused by an increase in atmospheric CO2.
We already know what will happen if an asteroid this size strikes Earth again—global devastation. But drilling in the area of the impact will tell us a lot about how geological and ecological processes respond to this type of devastation.
Illustration of the “Beacon” inflating from its canister after reaching orbit. The Mayak Project used the Russian version of Kickstarter called Boomstarter to fund the project. Credit: cosmomayak.ru / Mayak Project
Artist’s view of the proposed Mayak (Beacon) satellite fully unfurled and orbiting Earth. Credit: cosmomayak.ru / Mayak Project
We may soon look up and see a satellite brighter than the space station and even Venus gliding across the night sky if a Russian crowdfunding effort succeeds. An enthusiastic team of students from Moscow University of Mechanical Engineering are using Boomstarter, the Russian equivalent of Kickstarter, to raise the money needed to build and launch a pyramid-shaped satellite made of highly reflective material they’re calling Mayak, Russian for “Beacon”.
Young engineers at Moscow University explain the Mayak Project
To date they’ve collected more than $23,000 or 1.7 million rubles. Judging from the video, the team has built the canister that would hold the satellite (folded up inside) and performed a high-altitude test using a balloon. If funding is secured, Beacon is scheduled to launch on a Soyuz-2 rocket from the Baikonur Cosmodrome in the second quarter of this year.
Illustration of the “Beacon” inflating from its canister after reaching orbit. The Mayak Project used the Russian version of Kickstarter called Boomstarter to fund the project. Credit: cosmomayak.ru / Mayak Project
Once in orbit, Beacon will inflate into a pyramid with a surface area of 172 square feet (16 square meters). Made of reflective metallized film 20 times thinner than a human hair, the satellite is expected to become the brightest man-made object in orbit ever. That title is currently held by the International Space Station which can shine as brightly as magnitude -3 or about three times fainter than Venus. The brightest satellites, the Iridiums, can flare to magnitude -8 (as bright as the crescent moon) but only for a few seconds before fading back to invisibility. They form a “constellation” of some 66 satellites that provide data and voice communications.
A student at the Mayak Lab in Moscow describes the container used to hold the reflective “Beacon” satellite. Credit: cosmomayak.ru / Mayak Project
A concurrently-developed mobile app would allow users to know when Beacon would pass over a particular location. The students hope to achieve more than just track a bright, moving light across the sky. According to their website,the goal of the project is the “popularization of astronautics and space research in Russia, as well as improving the attractiveness of science and technology education among young people.” They want to show that almost anyone can build and send a spacecraft into orbit, not just corporations and governments.
Further, the students hope to test aerodynamic braking in the atmosphere and find out more about the density of air at orbital altitudes. Interested donors can give anywhere from 300 rubles (about $5) up 300,000 ($4,000). The more money, the more access you’ll have to the group and news of the satellite’s progress; the top donor will get invited to watch the launch on-site.
Liftoff! Moscow University students release the satellite on a test run. Credit: cosmomayak.ru / Mayak Project
Once finished with the Mayak Project, the team wants to built another version that uses that atmosphere for braking its speed and returning it — and future satellites — safely back to Earth without the need for retro-rockets.
I think all these goals are worthy, and I admire the students’ enthusiasm. I only hope that satellite launching doesn’t become so cheap and popular that we end up lighting up the night sky even further. What do you think?
Galaxy GN-z11 superimposed on an image from the GOODS-North survey. Credit: NASA/ESA/P. Oesch (Yale University)/G. Brammer (STScI)/P. van Dokkum (Yale University)/G. Illingworth (University of California, Santa Cruz)
Since it was first launched in 1990, the Hubble Space Telescope has provided people all over the world with breathtaking views of the Universe. Using its high-tech suite of instruments, Hubble has helped resolve some long-standing problems in astronomy, and helped to raise new questions. And always, its operators have been pushing it to the limit, hoping to gaze farther and farther into the great beyond and see what’s lurking there.
And as NASA announced with a recent press release, using the HST, an international team of astronomers just shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe. In so doing, they have not only looked deeper into the cosmos than ever before, but deeper into it’s past. And what they have seen could tell us much about the early Universe and its formation.
Due to the effects of special relativity, astronomers know that when they are viewing objects in deep space, they are seeing them as they were millions or even billions of years ago. Ergo, an objects that is located 13.4 billions of light-years away will appear to us as it was 13.4 billion years ago, when its light first began to make the trip to our little corner of the Universe.
An international team of scientists has used the Hubble Space Telescope to spectroscopically confirm the farthest galaxy to date. Credits: NASA/ESA/B. Robertson (University of California, Santa Cruz)/A. Feild (STScI)
This is precisely what the team of astronomers witnessed when they gazed upon GN-z11, a distant galaxy located in the direction of the constellation of Ursa Major. With this one galaxy, the team of astronomers – which includes scientists from Yale University, the Space Telescope Science Institute (STScI), and the University of California – were able to see what a galaxy in our Universe looked like just 400 million years after the Big Bang.
Prior to this, the most distant galaxy ever viewed by astronomers was located 13.2 billion light years away. Using the same spectroscopic techniques, the Hubble team confirmed that GN-z11 was nearly 200 million light years more distant. This was a big surprise, as it took astronomers into a region of the Universe that was thought to be unreachable using the Hubble Space Telescope.
In fact, astronomers did not suspect that they would be able to probe this deep into space and time without using Spitzer, or until the deployment the James Webb Space Telescope – which is scheduled to launch in October 2018. As Pascal Oesch of Yale University, the principal investigator of the study, explained:
“We’ve taken a major step back in time, beyond what we’d ever expected to be able to do with Hubble. We see GN-z11 at a time when the universe was only three percent of its current age. Hubble and Spitzer are already reaching into Webb territory.”
The Hubble Space Telescope in 1997, after its first servicing mission. Credit: NASA
In addition, the findings also have some implications for previous distance estimates. In the past, astronomers had estimated the distance of GN-z11 by relying on Hubble and Spitzer’s color imaging techniques. This time, they relied on Hubble’s Wide Field Camera 3 to spectroscopically measure the galaxies redshift for the first time. In so doing, they determined that GN-z11 was farther way than they thought, which could mean that some particularly bright galaxies who’s distanced have been measured using Hubble could also be farther away.
The results also reveal surprising new clues about the nature of the very early universe. For starters, the Hubble images (combined with data from Spitzer) showed that GN-z11 is 25 times smaller than the Milky Way is today, and has just one percent of our galaxy’s mass in stars. At the same time, it is forming stars at a rate that is 20 times greater than that of our own galaxy.
As Garth Illingworth – one of the team’s investigator’s from the University of California, Santa Cruz – explained:
“It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon. This new record will likely stand until the launch of the James Webb Space Telescope.”
Last, but not least, they provide a tantalizing clue as to what future missions – like the James Webb Space Telescope – will be finding. Once deployed, astronomers will likely be looking ever farther into space, and farther into the past. With every step, we are closing in on seeing what the very first galaxies that formed in our Universe looked like.
Recent images sent by NASA's New Horizons spacecraft show possible clouds floating over the frozen landscape including the streaky patch at right. Credit: NASA/JHUAPL/SwR
Recent images sent by NASA’s New Horizons spacecraft show possible clouds floating over the frozen landscape including the hazy streak right of center. Credit: NASA/JHUAPL/SwRI
I think we were all blown away when the New Horizons spacecraft looked back at Pluto’s dark side and returned the first photos of a surprisingly complex, layered atmosphere. Colorless nitrogen along with a small percentage of methane make up Pluto’s air. Layers of haze are likely created when the two gases react in sunlight to form tiny, soot-like particles called tholins. These can ultimately grow large enough to settle toward the surface and coat and color Pluto’s icy exterior.
Close up of the back side of Pluto taken by New Horizons shows multiple layers of haze in its mostly nitrogen atmosphere. Credit: NASA/JHUAPL/SwRI
Now it seems Pluto’s atmosphere is capable of doing even more — making clouds! In an e-mail exchange with New Scientist, Lowell Observatory astronomer Will Grundy discusses the possibility that streaks and small condensations within the hazes might be individual clouds. Grundy also tracked a feature as it passed over different parts of the Plutonian landscape below, strongly suggesting a cloud. If confirmed, they’d be the first-ever clouds seen on the dwarf planet, and a sign this small 1,473-mile-wide (2,370 km) orb possesses an even more complex atmosphere than imagined.
Faint arrows along Pluto’s limb point to possible clouds in a low altitude haze layer. More distinct possible clouds are arrowed at left. Credit: NASA/JHUAPL/SwRI15 minutes after its closest approach, New Horizons snapped this image of the smooth expanse of Sputnik Planum (right) flanked to the west (left) by rugged mountains up to 11,000 feet (3,500 meters) high, including the informally named Norgay Montes in the foreground and Hillary Montes on the skyline. The backlighting highlights more than a dozen layers of haze in Pluto’s tenuous but distended atmosphere. Credit: NASA/JHUAPL/SwRI
Given the onion-like layers of haze and potential clouds, perhaps we shouldn’t be surprise that it snows on Pluto. The New Horizons team announced the discovery this week of a chain of exotic snowcapped mountains stretching across the dark expanse of the informally named Cthulhu Regio. Cthulhu, pronounced kuh-THU-lu and named for a character in American horror writer H.P. Lovecraft’s books, stretches nearly halfway around Pluto’s equator, starting from the west of the vast nitrogen ice plain, Sputnik Planum. At 1,850 miles (3,000 km) long and 450 miles (750 km) wide, Cthulhu is a bit larger than the state of Alaska. But ever so much colder!
The upper slopes of Cthulhu’s highest peaks are coated with a bright material that contrasts sharply with the dark red color of the surrounding plains. Scientists think it’s methane ice condensed from Pluto’s atmosphere. The far right panel shows the distribution of methane ice on the surface. Credit: NASA/JHUAPL/SwRI
Cthulhu’s red color probably comes from a covering of dark tholins formed when methane interacts with sunlight. But new close-up images reveal that the region’s highest mountains appear coated with a much brighter material. Scientists think it’s methane, condensed as ice onto the peaks from Pluto’s atmosphere.
“That this material coats only the upper slopes of the peaks suggests methane ice may act like water in Earth’s atmosphere, condensing as frost at high altitude,” said John Stansberry, a New Horizons science team member.
Compositional data from the New Horizon’s Ralph/Multispectral Visible Imaging Camera (MVIC), shown in the right panel in the image above, shows that the location of the bright ice on the mountain peaks correlates almost exactly with the distribution of methane ice, shown in false color as purple.
New Horizons still has plenty of images stored on its hard drive, so we’re likely to see more clouds, frosty peaks and gosh-knows-what-else as the probe speeds ever deeper into space while returning daily postcards from its historic encounter.
As the director of “Star Wars: The Force Awakens,” and “Star Trek Into Darkness”, J.J. Abrams is no stranger to space narratives. But now he’s leaving behind light saber battles and warp drive chase sequences to tackle something a little more realistic.
Abrams’ newest project is a 9 part documentary series, called “Moon Shot,” that showcases 16 different teams of people competing for Google’s Lunar X-Prize. The teams of entrepreneurs, scientists, and inventors will have to engineer a spacecraft, have it land a rover on the Moon, travel 500 meters, and then transmit HD video and images back to Earth. And they have to have their launch contract verified by the end of 2017. This is a daunting task.
Though the Moon might appear rather placid, and even safe compared to some of the hostile environments Earthlings and their spacecraft have ventured to, it’s not an easy place to do business in. We’re getting used to seeing rovers and landers and orbiters visit the Moon in what seems like a work-a-day process. But the Moon is still a hostile place.
The temperature on the Moon fluctuates wildly. At its coldest, the temperature drops to a frigid -246 C (-412 F.) At its hottest, the temperature jumps to a scorching 100 C (212F.) A 350 C swing in temperatures is hard on equipment and requires robust designing and engineering.
Temperature fluctuation aside, there is also the increased radiation to contend with. The Moon lacks the magnetosphere and atmosphere that protects Earth from the full onslaught of the Sun, so sensitive electronics have to contend with that. And then there’s the dust, which can also be hard on equipment. Remember, the Google Lunar X-Prize is a competition to land a privately-funded robot on the Moon. Dealing with these formidable challenges as a small team is much harder, considering that the teams don’t have the resources that NASA and other groups have. But with $30 million in prize money at stake, we can expect to see some highly-motivated people competing.
Competitors include a German team backed by Audi (teams have to prove that they are 90% funded by private money,) a father and son working from a bedroom in Vancouver, a team of IT specialists from India, and a Japanese team from the Department of Aerospace Engineering at Tohoku University.
Though the science aspect of the series will no doubt be fascinating—the Japanese team has revealed that they will use VR to control their innovative camera system—it’s the stories of the people trying to win the prize that should be even more gripping. Who are these people? What drives these people to do such a thing?
The series will be available for viewing on YouTube on March 17, 2016, and on Google Play on March 15, 2016. Can’t wait to check it out.
An artist's illustration of the MOM orbiter at Mars. Image: By Nesnad - Own work, GFDL, https://commons.wikimedia.org/w/index.php?curid=29435816
Science—like literature and the arts—helps nations cooperate together, even when they’re in conflict politically. The USA and Russia are in conflict over the Ukraine and Syria, yet both nations still cooperate when it comes to the International Space Station. With that in mind, it’s great to see other nations—in this case India—taking on a greater role in space exploration and sharing their scientific results.
India’s Mars Orbiter Mission (MOM) probe has been in orbit around Mars since September 2014, after being launched in November 2013. Though the Indian Space Research Organization (ISRO) has released plenty of pictures of the surface of Mars, they haven’t released any scientific data. Until now.
A beautiful full-disc image of Mars captured by MOM. Image: ISRO/MOM.
In September 2015, MOM’s orbit was adjusted to bring it to within 260 km of Mars’ surface, significantly closer to the surface than the usual 400 km altitude. This manoeuver allowed one of MOM’s six instruments, the Mars Exospheric Neutral Composition Analyzer (MENCA), to measure the atmospheric composition at different altitudes. The sensor measured carbon dioxide, oxygen, nitrogen and carbon monoxide to see how they were distributed at different altitudes.
MOM’s activity at Mars is important for a couple of reasons. Its results confirm the results of other probes that have studied Mars’ atmosphere. And confirmation is an important part of science. But there’s another reason why MOM is important, and this centres around the search for evidence of life on the Red Planet.
Methane is considered a marker for the presence of life. It’s not an absolute indicator that life is or was present, but it’s a good hint. One of MOM’s sensors is the Methane Sensor for Mars (MSM.) Methane has been detected in Mars’ atmosphere before, but these could have been spikes, and not a strong indicator of living processes. If MSM provides stronger data indicating a consistent methane presence, that would be very interesting.
Releasing these results is also vindication for ISRO. In 2008, ISRO released data from their lunar mission, Chandrayaan-1, showing the presence of water on the Moon. Those results, which were gathered with an instrument called Chandra’s Altitudinal Composition Explorer (CHACE) were rejected by several scientific publications, on the grounds that the results were contaminated. Only when they were confirmed by another of Chandrayaan-1’s instruments—the Moon Mineralogy Mapper (M3)—were the results accepted.
But MOM’s MENCA instrument is based on the CHACE instrument aboard Chandrayaan-1, so ISRO feels that MENCA’s success in the atmosphere at Mars vindicates CHACE’s results on the Moon. And rightly so.
You can read a blog post by Syed Maqbool Ahmed at the Planetary Society, where he talks about the success of MOM’s MENCA, and how it vindicates ISRO’s earlier results with CHACE that showed the presence of water on the Moon.
MOM is India’s first interplanetary mission, and is expected to last until its fuel runs out, which could take many years. India is the first Asian nation to make it to another planet, and the first of any nation to make it to Mars on their first attempt. Not bad for a mission that was initially considered to be only a technology demonstration mission.
A team of astronomers from UCLA searched for "technosignatures" in the Kepler field data. Credit and Copyright: Danielle Futselaar
Very recently, a team of scientists from the Commonwealth Scientific and Industrial Research Organization (CSIRO) achieved an historic first by being able to pinpoint the source of fast radio bursts (FRBs). With the help of observatories around the world, they determined that these radio signals originated in an elliptical galaxy 6 billion light years from Earth. But as it turns out, this feat has been followed by yet another historic first.
In all previous cases where FRBs were detected, they appeared to be one-off events, lasting for mere milliseconds. However, after running the data from a recent FRB through a supercomputer, a team of scientists at McGill University in Montreal have determined that in this instance, the signal was repeating in nature. This finding has some serious implications for the astronomical community, and is also considered by some to be proof of extra-terrestrial intelligence.
FRBs have puzzled astronomers since they were first detected in 2007. This event, known as the Lorimer Burst, lasted a mere five milliseconds and appeared to be coming from a location near the Large Magellanic Cloud, billions of light years away. Since that time, a total of 16 FRBs have been detected. And in all but this one case, the duration was extremely short and was not followed up by any additional bursts.
The NSF’s Arecibo Observatory, which is located in Puerto Rico, is the world largest radio telescope. Credit: NAIC
Because of their short duration and one-off nature, many scientists have reasoned that FRBs must be the result of cataclysmic events – such as a star going supernova or a neutron star collapsing into a black hole. However, after sifting through data obtained by the Arecibo radio telescope in Puerto Rico, a team of students from McGill University – led by PhD student Paul Scholz – determined that an FRB detected in 2012 did not conform to this pattern.
In an article published in Nature, Scholz and his associates describe how this particular signal – FRB 121102 – was followed by several bursts with properties that were consistent with the original signal. Running the data which was gathered in May and June through a supercomputer at the McGill High Performance Computing Center, they determined that FRB 121102 had emitted a total of 10 new bursts after its initial detection.
This would seem to indicate that FRBs have more than just one cause, which presents some rather interesting possibilities. As Paul Scholz told Universe Today via email:
“All previous Fast Radio Bursts have only been one-time events, so a lot of explanations for them have involved a cataclysmic event that destroys the source of the bursts, such as a neutron star collapsing into a black hole. Our discovery of repeating bursts from FRB 121102 shows that the source cannot have been destroyed and it must have been due to a phenomenon that can repeat, such as bright pulses from a rotating neutron star.”
The Parkes Telescope in New South Wales, Australia. Credit: Roger Ressmeyer/Corbis
Another possibility which is making the rounds is that this signal is not natural in origin. Since their discovery, FRBs and other “transient signals” – i.e. seemingly random and temporary signals – from the Universe have been the subject of speculation. As would be expected, there have been some who have suggested that they might be the long sought-after proof that extra-terrestrial civilizations exist.
For example, in 1967, after receiving a strange reading from a radio array in a Cambridge field, astrophysicist Jocelyn Bell Burnell and her team considered the possibility that what they were seeing was an alien message. This would later be shown to be incorrect – it was, in fact, the first discovery of a pulsar. However, the possibility these signals are alien in origin has remained fixed in the public (and scientific) imagination.
This has certainly been the case since the discovery of FRBs. In an article published by New Scientistsin April of 2015 – titled “Cosmic Radio Plays An Alien Tune” – writer and astrophysicist Sarah Scoles explores the possibility of whether or not the strange regularity of some FRBs that appeared to be coming from within the Milky Way could be seen as evidence of alien intelligence.
However, the likelihood that these signals are being sent by extra-terrestrials is quite low. For one, FRBs are not an effective way to send a message. As Dr. Maura McLaughlin of West Virginia University – who was part of the first FRB discovery – has explained, it takes a lot of energy to make a signal that spreads across lots of frequencies (which is a distinguishing feature of FRBs).
For decades, scientists have been exploring the possibility that radio bursts are signals from alien civilizations. Credit: AdamBurn/DeviantArt
And if these bursts came from outside of our galaxy, which certainly seems to be the case, they would have to be incredibly energetic to get this far. As Dr. McLaughlin explained to Universe Today via email:
“The total amount of power required to produce just one FRB pulse is as much as the Sun produces in a month! Although we might expect extraterrestrial civilizations to send short-duration signals, sending a signal over the very wide radio bandwidths over which FRBs are detected would require an improbably immense amount of energy. We expect that extraterrestrial civilizations would transmit over a very narrow range of radio frequencies, much like a radio station on Earth.
But regardless of whether these signals are natural or extra-terrestrial in origin, they do present some rather exciting possibilities for astronomical research and our knowledge of the Universe. Moving forward, Scholz and his team hope to identify the galaxy where the radio bursts originated, and plans to use test out some recently-developed techniques in the process.
“Next we would like to localize the source of the bursts to identify the galaxy that they are coming from,” he said. “This will let us know about the environment around the source. To do this, we need to use radio interferometry to get a precise enough sky location. But, to do this we need to detect a burst while we are looking at the source with such a radio telescope array. Since the source is not always bursting we will have to wait until we get a detection of a burst while we are looking with radio interferometry. So, if we’re patient, eventually we should be able to pinpoint the galaxy that the bursts are coming from.”
In the end, we may find that rapid burst radio waves are a more common occurrence than we thought. In all likelihood, they are being regularly emitted by rare and powerful stellar objects, ones which we’ve only begun to notice. As for the other possibility? Well, we’re not saying it’s aliens, but we’re quite sure others will be!
A colorized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. Image: NASA/JPL-Caltech/ Arizona State University
“What happened to Mars?” is one of the most compelling questions in space science. It probably wasn’t always the dead, dry, cold place it is now. Did its core cool and stop rotating, allowing the full glare of the sun to blast away its atmosphere and water, and kill anything that may have lived there? Was it struck by a large body, which incinerated its atmosphere, and led to its demise? Were there other causes?
According to a new research paper from Sylvain Bouley at the University of Paris-South, and his colleagues, it may have been a massive, ancient outpouring of molten rock that threw Mars off kilter and helped change Mars into what it is today.
The Tharsis region is an ancient lava complex on Mars that dates back to between 4.1 billion and 3.7 billion years ago. It’s located in Mars’ Western Hemisphere, right near the equator. It’s made up of three huge shield volcanoes—Arsia Mons, Pavonis Mons, and Ascraeus Mons. Collectively, they’re known as Tharsis Montes. (Olympus Mons, the largest volcano in the Solar System, is not a part of the Tharsis complex, though it is near it.)
Tharsis is over 5,000 km across and over 10 miles thick, making it the largest volcanic complex in the Solar System. That much mass positioned after Mars was already formed and had an established rotation would have been cataclysmic. Think what would happen to Earth if Australia rose up 10 miles.
An image of the Syria-Thaumasia region of the Tharsis complex, showing the volcano Arsia Mons on the left, and Valles Marineris on the northern edge. Brown areas are the highest altitude. Open Source Image: Arizona State University, JMars.
The new paper, published on March 2nd, 2016, in the journal Nature, says that the position of the Tharsis complex would have initiated a True Polar Wander (TPW.) Basically, what this means is that Tharsis’ huge mass would have forced Mars to shift its rotation, so that the location of Tharsis became the new equator.
It was thought that the emergence of Tharsis made Martian rivers—which formed later—flow the direction they do. But the study from Bouley and his colleagues shows that Martian rivers and valleys formed first—or maybe concurrently—and that the Tharsis TPW deformed the planet later.
The authors of the study calculated where the Martian poles would have been prior to Tharsis, and looked for evidence of polar conditions at those locations. The location of this ancient north pole contains a lot of ice today, and the location of the ancient south polar region also shows evidence of water.
What it all adds up to is that the disappearance of water on Mars probably happened at the same time as the TPW. Whether the appearance of the Tharsis lava complex, and the resulting cataclysmic shifting of Mars’ rotational orientation, were the cause of Mars losing its climate is not yet known for sure. But this study shows that the ancient volcanic cataclysm did at least help shape Mars into what it is today.
The view from the beach on Titan? A recent study has shown that Titan's seas experience very low waves, making it a perfect place for a probe to set down.Credit: NASA
Space is mostly vast and empty. So whenever we notice something like ripples on a lake, on the frozen moon of a gas giant, we take notice.
At a meeting of the American Geophysical Union in San Francisco this week, it was reported that Cassini images of Saturn’s moon Titan showed light being reflected from the Ligeia Mare, a frigid sea of hydrocarbons on that moon. Subsequent images showed the same phenomenon on two other seas of Titan, as well. These are thought to be waves, the first waves detected anywhere other than Earth, and suggest that Titan has more geophysical activity than previously thought.
Surfers on Earth, known for seeking out remote and secretive locations, shouldn’t get too excited. According to mathematical modelling and radar imagery, these waves are only 1.5 cm (0.6 inches) tall, and they’re moving only 0.7 metres (2.3 feet) per second. Plus, they’re on a sea of liquid hydrocarbons—mostly methane—that is a frigid -180 degrees Celsius (-292 F.)
The left image shows a mosaic of images of Titan taken by the Cassini spacecraft in near infrared light. Titan’s polar seas are visible as sunlight glints off of them. The right image is a radar image of Kraken Mare. Credit: NASA Jet Propulsion Laboratory.
Planetary scientists are taking note, though, because these waves show that Titan has an active environment, rather than just being a moon frozen in time. It’s thought that the change in seasons on Titan is responsible for these waves, as Titan begins its 7 year summer. Processes related to the changing seasons on Titan have created winds, which have cause these ripples.
There’s other evidence of active weather on Titan, including dunes, river channels, and shorelines. But this is the first observation of active weather phenomena, rather than just the results. All together, it shows that Titan is a more active, dynamic environment than previously thought.
Titan’s hydrocarbon lakes are thought to be up to 200 metres (656 ft.) deep, and are clustered around the north polar region. Just one of its lakes is thought to contain approximately 9,000 cubic km of methane, which is about 40 times more than the Earth’s reserves of oil and gas.
Titan is the second largest moon in the Solar System, second only to Ganymede, and both moons are larger than the planet Mercury. Titan was discovered in 1655 by Christiaan Huygens.
The planet Venus, as imaged by the Magellan 10 mission. The planet's inhospitable surface makes exploration extremely difficult. Credit: NASA/JPL
The first spacecraft to reach the surface of another world was the Soviet Venera 3 probe. Venera 3 crash-landed on the surface of Venus on March 1, 1966, 50 years ago. It was the 3rd in the series of Venera probes, but the first two never made it.
Venera 3 didn’t last long. It survived Venus’ blistering heat and crushing atmospheric pressure for only 57 minutes. But because of that 57 minutes, its place in history is cemented.
With a temperature of 462 degree C. (863 F.,) and a surface pressure 90 times greater than Earth’s, Venus’ atmosphere is the most hostile one in the Solar System. But Venus is still a tantalizing target for exploration, and rather than letting the difficult conditions deter them, Venus is a target that NASA thinks it can hit.
The Venus Landsail—called Zephyr—could be the first craft to survive the hostile environment on Venus. If approved, it would launch in 2023, and spend 50 days on the surface of Venus. But to do so, it has to meet several challenges.
NASA thinks they have the electronics that can withstand the heat, pressure, and corrosive atmosphere of Venus. Their development of sensors that can function inside jet engines proves this, and is the kind of breakthrough that really helps to advance space exploration. They also have solar cells that should function on the surface of Venus.
But the thick cloud cover will prevent the Zephyr’s solar cells from generating much electricity; certainly not enough for mobility. They needed another solution for traversing the surface of Venus: the land sail.
An artist’s conception of what NASA’s Zephyr Landsail might look like on the surface of Venus. Image: NASA Glenn Research Center.
Venus has very slow winds—less than one meter per second—but the high density of the atmosphere means that even a slow wind will allow Zephyr to move effectively around the Venusian surface. But a land sail will only work on a surface without large rocks in the way. Thanks to the images of the surface of Venus sent back to Earth from the Venera probes, we know that a land sail will work, at least in some parts of the Venusian surface.
So Venus is back on the menu. With all the missions to other places in the Solar System, Venus is kind of forgotten, right here in our own backyard. But there’s actually a pretty rich history of missions to Venus, even though an extended visit to the surface has been out of reach. Since it’s been 50 years since Venera 3 reached the surface, now is a good time to look back at the history of the exploration of Venus.
The Soviet Union dominated the exploration of Venus. The Venera probes went all the way up to Venera 16, though some were orbiters rather than landers. From one perspective, the whole Venera program was plagued with problems. Many of the craft failed completely, or else had malfunctions that crippled them. But they still returned important information, and achieved many firsts, so the Venera program overall has to be considered a success.
The Soviet Union did not like to acknowledge or talk about space missions that failed. They often changed the name of a mission if it failed, so the names and numbers can get a little confusing.
Venera 4 was actually the first spacecraft to transmit any data from another world. On October 18th, 1967, it transmitted data from Venus’ atmosphere, but none from the surface. There were actually ten Venera missions before it, but most of them didn’t make it to Venus, suffering explosions or failing to leave Earth’s orbit and crashing back to the surface of Earth. Two of the Venera probes, numbers 1 and 2, suffered a loss of communications, so their fate is unknown.
After Venera 4’s relative success, there was another failed craft that fell back to Earth. Then on May 16th, 1969, Venera 5 successfully entered Venus’ atmosphere, and made it to within 26 kilometers of the surface before being crushed by the pressure. The next day—the Soviets often launched missions in pairs—Venera 6 entered the atmosphere of Venus and successfully transmitted data. It made it deeper into the atmosphere before being crushed within 11 kilometers of the surface.
Venera 7 was a successful mission. On December 15th, 1970, it landed on the surface of Venus and survived for 23 minutes. Venera 7 was the very first broadcast from the surface of another planet.
In 1972 Venera 8 survived for 50 minutes on the surface, followed by Venera 9 in 1975. Venera 9 survived for 53 minutes and sent back the first black and white images of the surface of Venus. Venera 10 landed 3 days after Venera 9 and survived 65 minutes, and also sent photos back. Grainy and blurry, but still amazing!
Images from Venera 9 (top) and Venera 10 (bottom). Public Domain Images, courtesy of NASA/National Space Science Data Center.
December 1978 saw the arrival of Venera 11 and 12, surviving 95 and 112 minutes respectively. Venera 11’s camera failed, but Venera 12 recorded what is thought to be lightning.
In March 1982, Venera 13 and 14 arrived. 13 took the first color images of the surface of Venus, and both craft took soil samples. Venera 15 and 16—both orbiters—arrived in 1983 and mapped the northern hemisphere.
The first color pictures taken of the surface of Venus by the Venera-13 space probe. Credit: NASA
The Soviet Unions final missions to Venus were Vega 1 and Vega 2, in 1985, which combined landings on Venus and flybys of Halley’s comet into each mission. Vega 1’s surface experiments failed, while Vega 2 transmitted data from the surface for 56 minutes.
The United States has also launched several mission to Venus, though none have been landers. Spacecraft in the Mariner series studied Venus from orbit and during flybys, sometimes getting quite close to the cloud tops.
In 1962 and 1967, Mariner 2 and 5 completed flybys of Venus and transmitted data back to Earth. Mariner 5 came as close as 4094 km of the surface. In February 1974, Mariner 10 approached Venus and came to within 5,768 km. It returned color images of Venus, and then used gravitational assist—the first spacecraft to ever do so—to propel itself to Mercury.
Mariner 10’s Venus. Image: NASA
In December 1978, the Pioneer Venus Orbiter reached Venus and studied the atmosphere, surface, and other aspects of Venus. It lasted until August 1992, when its fuel ran out and it was destroyed when it entered the atmosphere.
On August 1990, the Magellan mission reached Venus and used radar to map the surface of the planet. On October 1994, Magellan entered the Venusian atmosphere and was destroyed, but not before successfully mapping over 99% of the planet’s surface.
Deployment of Magellan with Inertial Upper Stage booster. Credit: NASA
Messenger was a NASA mission to Mercury that was launched in August 2004. It did two flybys of Venus, in October 2006 and June 2007.
The Venus Express, a European Space Agency mission, orbited Venus and studied the atmosphere and plasma of Venus. Of special interest to Venus Express was the study of what role greenhouse gases played in the formation of the atmosphere.
In 2010, the Japanese Space Agency launched Akatsuki, also known as the Venus Climate Orbiter. It’s role is to orbit Venus and study the atmospheric dynamics. It will also look for evidence of lightning and volcanic activity.
If there’s one thing that space exploration keeps teaching us, it’s to expect the unexpected. Who knows what we’ll find on Venus, if the Land Sail mission is approved, and it survives for its projected 50 days.
