A rain of metallic stardust lit up the skies of Mars in the wake of the close passage of Comet Siding Spring, which roared past the Red Planet last October.
This is according to the instruments aboard NASA’s MAVEN spacecraft, which made the first direct detection of sodium, magnesium, aluminum, chromium, nickel, copper, zinc, iron and other metals high in the Martian atmosphere that can be linked directly to the material sloughing off the comet.
We’re told to never judge a book by its cover, but it’s apparently fine to judge what lies inside Mars by listening to the echoes of meteorite impacts.
We know very little about the interior of the Red Planet. We know that once it had a global magnetic field and active volcanoes, but it’s unclear if the core is still molten or not. If it is, plate tectonics and earthquakes (which are called marsquakes on Mars) are a possibility.
To find out, the next spacecraft to arrive on Mars will come equipped with precise seismometers to detect tremors. The InSight Lander will listen carefully for seismic waves caused by meteorites, and use the data to make some educated guesses at what materials it passed through along the way.
A tiny, clay-filled bubble found in a Martian meteorite boosts the chances that Mars was habitable for life, according to a new study.
While scientists have not yet found proof that life exists on Mars, NASA’s Curiosity rover has found evidence that the planet could have supported life in the past. Clay minerals discovered by the rover suggest liquid water, in rivers, lakes and streams, once flowed on Mars’ surface.
The new study also discovered evidence for clay minerals on Mars, but the clues come from a Martian meteorite that fell in Egypt in 1911.
This rock encountered by NASA’s Curiosity Mars rover is an iron meteorite called “Lebanon,” similar in shape and luster to iron meteorites found on Mars by the previous generation of rovers, Spirit and Opportunity. Lebanon is about 2 yards or 2 meters wide (left to right, from this angle). The smaller piece in the foreground is called “Lebanon B.”
This view combines a series of high-resolution circular images taken by the Remote Micro-Imager (RMI) of Curiosity’s Chemistry and Camera (ChemCam) instrument with color and context from rover’s Mast Camera (Mastcam). The component images were taken during the 640th Martian day, or sol, of Curiosity’s work on Mars (May 25, 2014).
The imaging shows angular shaped cavities on the surface of the rock. One possible explanation is that they resulted from preferential erosion along crystalline boundaries within the metal of the rock. Another possibility is that these cavities once contained olivine crystals, which can be found in a rare type of stony-iron meteorites called pallasites, thought to have been formed near the core-mantle boundary within an asteroid.
A huge meteorite impact on Mars five million years ago blasted toward Earth many of the rocks that scientists scrutinize to learn more about the Red Planet, a new study reveals.
The cosmic crash left a 34-mile-wide (55 kilometers) gouge on Mars called Mojave Crater and is the source of all “shergottite” or igneous rock Martian meteorites found on Earth, researchers say. Examining the crater and the meteorites also led to new revelations about how old the rocks are.
A meteorite reveals clues to how Mars lost its thick, carbon dioxide-rich atmosphere and became a cold, rocky desert, researchers say.
They say the Lafayette meteorite shows signs of carbonation – where minerals absorb CO2 in a reaction with water.
Mars lost its protective blanket about 4 billion years ago, perhaps because of the loss of its magnetic field, space impacts, or chemical processes.
Carbonation may be the key factor, they write in Nature Communications.
Case closed. After several decades of speculation and the gathering of imperfect evidence, Mars rover Curiosity has positively identified hundreds of meteorites found all over the Earth as Martians. The discovery is not unexpected, but it allows the science to go forward with renewed confidence in conjectures about the Red Planet. In particular, Curiosity’s findings could help scientists figure out exactly how Mars lost the vast majority of its atmosphere, why, and how long ago it happened.
Arizona State University’s Center for Meteorite Studies has acquired a significant new sample for its collection, a rare martian meteorite that fell in southern Morocco in July 2011. It is the first martian fall in around fifty years.
Since the observed fall of the famed Ensisheim meteorite in 1492, there have been around 1,200 recovered meteorite falls. A “fall” is a meteorite that was witnessed by someone as it fell from the sky, whereas a “find” is a meteorite that was not observed to fall but was later found and collected. Only a handful of witnessed meteorite falls occur each year.
The chance of finding a meteorite is exceedingly small. The chance of witnessing a meteorite fall and finding it is even smaller – and the probability that the fall is a martian meteorite is smaller yet.
A meteorite that fell to Earth last July in Morocco has proven to be a rare chunk of Mars. Only a handful of Martian meteorites are known, and only five (counting the new find) come from meteorites whose fall was witnessed. That’s important because it tells scientists how long it has been lying on the ground, and therefore how much contamination it might have picked up. In this case, about a dozen pieces (such as the one shown, right), totalling several kilograms, were recovered from Morocco in late December.
“Because it’s only been on the ground for six months or less, it hasn’t been exposed to much contamination,” says Chris Herd, a planetary geologist specializing in meteorites at the University of Alberta, Edmonton, Canada. Herd chairs an international meteoritics committee that yesterday certified the rocks as coming from Mars and approved their name – Tissint – in honour of the village near which they were found.
Exactly a century ago, on June 28, 1911, an explosion shook the Nakhla region of Alexandria in Egypt at 9 a.m. Soon after, around 40 chunks of meteorite debris from the high altitude blast rained down. 22 pounds (10 kilograms) of the bolide were recovered by witnesses of this cosmic event.
The Smithsonian received two samples of the Nakhla meteorite the following August and then acquired a larger 480 gram (one pound) piece in 1962 (pictured top). By the 1970’s, the Smithsonian had collected 650 grams (1.4 pounds) of the meteorite.
