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This week, researchers are getting ready to learn about earth and Mars, in places that you might not expect.

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Space is risky business, and  scientists and engineers can spend   decades developing, constructing, and testing equipment before a spacecraft  gets anywhere near the launch pad. So, we got some exciting news  last week when NASA announced that the Psyche spacecraft team got the green  light to start putting everything together. If all goes well, the Psyche mission will  depart for the asteroid Psyche in August 2022.

The asteroid is officially designated 16 Psyche, and it’s orbiting the Sun in the  asteroid belt between Mars and Jupiter. The rock is about 226 kilometers across, and  based on things like its size and presumed mass,   it seems to mostly be made of  metals like iron and nickel — the same metals found in Earth’s core. That’s not to say that,  like, Psyche came from Earth.

But researchers do think the asteroid  may be the core of an old protoplanet, one that formed and was mostly  demolished by collisions   during the formation of the solar system. So by studying this far-flung asteroid, scientists  might be able to learn more about Earth’s insides, which are way more difficult to visit  despite being literally right underneath us. But!

Before it gets to the asteroid,  the spacecraft has to launch, and before it launches, it has to be put together. So, NASA spacecraft go through a few phases. It starts with Phase A, where the team  develops a basic concept for the mission.

And it ends with Phase F, where the  mission is officially shut down. Until recently, Psyche was in Phase C, where  the goal was to finalize the craft’s design, and manufacture all the scientific  instruments and other components. But now, after a thorough review, the news last  week was that those goals had been accomplished!

The mission was approved to enter Phase D. This means the team gets to  start the assembly process... and go through even more testing. And eventually,.

Phase D will turn into Phase E after  Psyche launches and reaches outer space. When the mission arrives at its asteroid in  2026, nearly a decade after it was approved, it will give us our first opportunity  to study a metallic asteroid up close — as opposed to the stony ones we’ve been to before. Over nearly two years, Psyche will study  the asteroid with a suite of instruments to   confirm what it’s made of, how old regions of the  surface are, what its gravitational field is like, and if it has a magnetic  field frozen into its rocks.

In particular, that magnetic field  will be especially interesting — because Earth’s magnetic field  is generated by its core. So if Psyche has remnants of a field like this, that could confirm the asteroid really  did start as the core of a protoplanet. And if it doesn’t?

We might just learn something unexpected  about the early solar system, instead. Not too far from Psyche, Mars’s moon  Phobos has also been in the news lately. Last week in the journal Nature Geoscience, scientists reported a way that we might  be able to study the moon in the future   to learn about what Mars looked like in the past.

So, Mars has been losing its  atmosphere for billions of years, thanks to things like interactions with  the air and particles from the Sun. We can tell because there’s ample evidence that the planet used to retain liquid water  on its surface. And on Mars in particular, you need a certain amount  of air pressure for that.

So, where did the gas go? Well, a lot of it just escaped into space. But in this new paper, one team proposed that some of those  atoms got trapped in the soil on Phobos.

And that future explorations could actually sample  them and bring them back to Earth for analysis. Now, Phobos isn’t a moon you hear a lot  about. Which is a bummer, because it’s great!

Despite being only 27 kilometers  across at its widest point, it’s actually the larger of Mars’s two moons. It also orbits super closely to the planet, about  60 times closer than our Moon is from the Earth. And although it’s small, we have  a lot of questions about it — including how it got there, and now, if it’s  hiding some of Mars’s old gas particles.

In their paper, this team used more than four  years of observations from NASA’s MAVEN orbiter. They studied the types of charged  particles in Phobos’s orbit, figuring out which ones came from  Mars, and which came from the Sun. Then, they calculated how many of those Martian  air particles could actually fall onto Phobos, and how deeply they might be buried.

In the end, the paper found that the moon   would have been absolutely bombarded  by these particles throughout history. And that they could be preserved a teeny  fraction of a meter beneath the moon’s surface. Like, like less than a hair’s width underground.  So, really not a lot of digging required.

Right now, only one side of Phobos faces Mars,  so that might be the best place to take a sample. But there could also be a range of  atmosphere records all over the moon. They could even include air  from billions of years ago, back when Mars was covered in liquid water.

So, studying these particles could help us  understand what the planet used to be like. And the great news is, we could learn more soon,   because there’s already a mission  to sample Phobos in the works. The Japan Aerospace Exploration Agency’s MMX   mission is expected to launch  in 2024.

And five years later, it will return the first  samples of Phobos’s surface. So just like Psyche, we’ll  have to wait to know more. But it’s sure to be worth it.

While we’re waiting on  results from Psyche and MMX, there’s plenty to learn in the meantime. Actually,  there’s so much to learn and so much to do   that finding the time to learn  something can be easier said than done. And that’s part of what led the  Blinkist team to make their app.

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