In just over two years, NASA will launch a probe to Psyche, an asteroid often dubbed as a “metal world”. Instead of being made mostly of ice, this asteroid’s composition is rocky-metallic. Why is it so important to study such a place? In short, the planet you stand on is made of the same materials.
Long ago, in the earliest epochs of the solar system, little bits of metallic rock like Psyche collided to form bigger worlds. These planetesimals are the building blocks of Earth, Venus, Mercury, Mars, and probably the cores of the giant planets. So, looking at this asteroid is like looking at the pieces that formed our planet.
About Psyche
Psyche was discovered in 1852 by Annibale de Gasparis. Its full official name is 16 Psyche, and it’s one of the ten most massive asteroids known in the solar system. It’s small, but it more than makes up for that with its interesting makeup. Psyche is very massive and has about 1 percent of the mass of the Asteroid Belt tied up in its 200-kilometer-wise body. It’s very likely to be the leftover iron core of a protoplanet, which would explain its massive properties. There has been water ice detected on its surface, probably delivered by impacts with other meteorites carrying ices.
Astronomers are still figuring out Psyche’s history, but the general story is that it probably was larger at one time (very early in the history of the solar system). As we all know, the infant solar system was a busy place. There were countless impacts among objects; some of them created larger objects. Some of them blew others apart.
That’s likely what happened to Psyche’s parent body. What was left is the current “version” of Psyche, and the rest of the pieces are scattered among the belt, or probably shattered into smaller ones by subsequent collisions. Another possibility is that the parent asteroid was leftover from the formation of the inner planets, and its outer layers battered away by continued collisions with other leftovers. Either story would explain why this asteroid is not much more than a metallic iron core with a layer of silicate rocks as a “surface”.
Asteroid Studies Teach about Past and Present
Planetary scientists are interested in asteroids for the role they play in the solar system. Certainly, they were part of our formational and collisional history. That “collisional part” is still a concern today, particularly about the asteroids that come close to our planet. Psyche isn’t one of those, however. The real value is in helping us understand that ancient time when Earth and other planets were still babies themselves.
The Psyche Orbiter
To explore this little world, NASA’s Psyche orbiter has to launch on 2022. If that happens, then it will head out on a trajectory that takes it past Mars for a gravity assist in 2023. The spacecraft arrives at Psyche in 2026. It will orbit for just under two years, studying the surface from ever-closer orbits.
The Psyche team has put together an interesting outreach plan. It’s called the “Innovation Toolkit”. First, if you want to learn more about the mission and spacecraft, they have a class for that! You sign up online and take the course at your own pace. The five-hour course gives a peek behind the scenes at what it’s like to plan a mission and carry it out.
The second course is a team-building exercise aimed at showing how diverse people can come together to focus on a single mission and “get ‘er done”. It’s all about collaboration and inclusivity to achieve some remarkable science goals.
The mission team plans to add other courses in the next couple of years, as the time for launch gets closer. There are also some very interesting videos and other activities available on the Psyche mission site. Check it out and follow along with the mission team as they closer to launch, and the exploration of Psyche.
