Posted on by Evan Gough

5,000 Exoplanets!

An artist's illustration of NASA's TESS with Earth and the Moon. Image Credit: NASA

Before NASA’s TESS (Transiting Exoplanet Survey Satellite) mission launched in 2018, astronomers tried to understand what it would find in advance. One study calculated that TESS would find between 4430 and 4660 new exoplanets during its primary two-year-long mission.

The primary mission (PM) is over, and TESS is in its extended mission (EM) now. The extended mission is 1.5 years old, and TESS has discovered 176 confirmed exoplanets and 5164 candidates. Scientists are still going through data from the primary mission, so the data might be hiding many more exoplanets. And TESS isn’t finished yet.

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Posted on by Evan Gough

Is That a Fossil on Mars? Non-Biological Deposits can Mimic Organic Structures

NASA's Perseverance rover, which is searching signs of ancient life on Mars. Some of the rocks in this image are volcanic in origin. (credit: NASA/JPL-Caltech/MSSS)
NASA's Perseverance rover, which is searching signs of ancient life on Mars. Some of the rocks in this image are volcanic in origin. (credit: NASA/JPL-Caltech/MSSS)

There’s nothing easy about searching for evidence of life on Mars. Not only do we somehow have to land a rover there, which is extraordinarily difficult. But the rover needs the right instruments, and it has to search in the right location. Right now, the Perseverance lander has checked those boxes as it pursues its mission in Jezero Crater.

But there’s another problem: there are structures that look like fossils but aren’t. Many natural chemical processes produce structures that mimic biological ones. How can we tell them apart? How can we prepare for these false positives?

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