A White Christmas on Mars.
A White Christmas on Mars.
Tag: geology
Data from Messenger now shows that as Mercury cooled it shrunk far more than earlier data had indicated.
Data from Messenger now shows that as Mercury cooled it shrunk far more than earlier data had indicated.
A new census of these ridges, called lobate scarps, has found more of them, with steeper faces, than ever before. The discovery suggests that Mercury shrank by far more than the previous estimate of 2-3 kilometres, says Paul Byrne, a planetary scientist at the Carnegie Institution for Science in Washington DC. He presented the results today at a meeting of the American Geophysical Union in San Francisco, California.
The finding helps explain how Mercury’s huge metallic core cooled off over time. It may also finally reconcile theoretical scientists, who had predicted a lot of shrinkage, with observers who had not found evidence of that — until now. “We are resolving a four-decades-old conflict here,” Byrne told the meeting.
Gale Crater held at least one lake in the past, and that lake existed for longer and more recently than expected.
More news from Curiosity: Gale Crater held at least one lake in the past, and that lake existed for longer and more recently than expected.
Curiosity has succeeded in dating the age of one of its rock samples, the first time this has ever been done remotely on another planet.
Curiosity has succeeded in dating the age of one of its rock samples, the first time this has ever been done remotely on another planet.
The second rock Curiosity drilled for a sample on Mars, which scientists nicknamed “Cumberland,” is the first ever to be dated from an analysis of its mineral ingredients while it sits on another planet. A report by Kenneth Farley of the California Institute of Technology in Pasadena, and co-authors, estimates the age of Cumberland at 3.86 billion to 4.56 billion years old. This is in the range of earlier estimates for rocks in Gale Crater, where Curiosity is working.
This is significant engineering and scientific news. In the past the only way to date the rocks on another world was to bring them back to Earth. This was how the moon’s geology was dated. On Mars, dating has only been done by crater counting, comparing those counts with those on the Moon, and then making a vague guess. To have the ability to date rocks remotely means that geologists can begin to sort out the timeline of Mars’s geology without having to bring back samples.
Seismic data now suggests that a volcano is beginning to stir far beneath the Antarctica icecap.
Seismic data now suggests that a volcano is beginning to stir far beneath the Antarctica icecap.
The article can’t resist noting how a really big eruption could melt a lot of ice and change the climate, neither of which is very likely.
New data suggesting the presence of granite on Mars also suggests that the planet is more geologically complex than previously believed.
The uncertainty of science: New data suggesting the presence of granite on Mars also suggests that the planet is more geologically complex than previously believed.
In my years of science writing, I can’t count the number of times I’ve written the phrase “more complex than previously believed.” For some reason, modern scientists seem to always assume that things will be simple, with one straight-forward answer. From gamma ray bursts to supernovae to planetary formation to whatever, the first example found and the first theory developed from that first example has repeatedly been expected to explain everything.
But that’s not how things work. Instead, the closer scientists have looked, the more complex and interesting things have always become. Many different things can cause gamma ray bursts. Supernovae come in many types. Solar systems don’t have to resemble ours. Everything is always more complex than you first believe.
Scientists would get things wrong less often if they simply kept this thought in mind, at all times.
The geology of Vesta as seen by Dawn appears to contradict the present models for that asteroid’s origin.
The uncertainty of science: The geology of Vesta as seen by Dawn appears to contradict the present models for that asteroid’s origin.
Geologists have determined that the magma reservoir under Yellowstone is much bigger than previously thought.
The uncertainty of science: Geologists have determined that the magma reservoir under Yellowstone is much bigger than previously thought.
Jamie Farrell, a postdoctoral researcher at the University of Utah, mapped the underlying magma reservoir by analysing data from more than 4,500 earthquakes. Seismic waves travel more slowly through molten rock than through solid rock, and seismometers can detect those changes.
The images show that the reservoir resembles a 4,000-cubic-kilometre underground sponge, with 6–8% of it filled with molten rock. It underlies most of the Yellowstone caldera and extends a little beyond it to the northeast.
The geologists also noted that the threat from a huge volcanic eruption is less of a concern than that of earthquakes.
Scientists believe they have identified the remains of a supervolcano on Mars.
Scientists believe they have identified the remains of a supervolcano on Mars.
This volcano would apparently be bigger than Mars’s four giant volcanoes that are still the biggest known in the solar system.
The strange and alien plant life of Socotra Island.
The strange and alien plant life of Socotra Island.
Data from the 2011 Virginia 5.6 magnitude earthquake suggests that the North American continent had drifted above a mantle hotspot millions of years ago.
Data from the 2011 Virginia 5.6 magnitude earthquake suggests that the North American continent had drifted above a mantle hotspot millions of years ago.
Want to land on an asteroid? Watch out, a gentle touchdown might cause avalanches everywhere!
Want to land on an asteroid? Watch out, a gentle touchdown might cause avalanches everywhere!
“Now I dream of snowboarding down a Martian sand dune on a block of dry ice.”
A new high resolution image from Mars Express illustrates the violent landslides and lava flows off the eastern flank of Olympus Mons, the solar system’s largest volcano.
A new high resolution image from Mars Express illustrates the violent landslides and lava flows off the eastern flank of Olympus Mons, the solar system’s largest volcano.
Asteroid 2012 DA14 might experience seismic activity when it zips pass the Earth tomorrow.
Asteroid 2012 DA14 might experience seismic activity, an asteroid quake, when it zips pass the Earth tomorrow.
[MIT scientist Richard] Binzel imagines what an astronaut floating alongside such an asteroid might see: “The surface could slowly sway or rock by a few centimeters. Other things to look for would be puffs of asteroid-dust rising from the surface and gentle avalanches on the steepest slopes of craters.” In rare cases, “rubble pile” asteroids might break apart during the encounter and then re-form as Earth recedes into the distance.
Curiosity has obtained its first drill sample.
Curiosity has obtained its first drill sample.
Researcher have found that the best way to protect the gothic cathedrals of Europe from air pollution might be to coat them with olive oil.
Researchers have found that the best way to protect the Gothic cathedrals of Europe from air pollution might be to coat them with olive oil.
Want to learn something of the geology of the Grand Canyon?
Want to learn something of the geology of the Grand Canyon? The Geological Society of America has just published a special volume of papers, with the introductory and afterword [pdf] chapters available online.
Those two chapters provide a very good layman’s summary of the geological state-of-the-art of the Grand Canyon. Very worthwhile reading if you plan to hike down in the near future.
A river on Titan.
The press lets Curiosity get the better of them
The big news is out. Today the eagerly awaited press conference at the American Geophysical Society meeting in San Francisco on the recent results from the Mars rover Curiosity was finally held. The announced results had been hyped like crazy when rumors began to spread a few weeks ago that Curiosity had discovered something truly spectacular.
Well, here are some of the headlines heralding the results.
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