This week, there has been excitement around two different asteroid missions.
Saturday morning, NASA launched the mission Psyche to the asteroid 16 Psyche, while the first results from samples by the OSIRIS-REx mission and the asteroid Bennu were revealed.
Both missions will give us insight into the beginning of the Earth, as well as what the future may hold for Earth and space exploration.
There are three main different types of asteroids.
C-type asteroids, the chondrites, which are dark, and mostly clay and silicates.
The asteroid Bennu is a c-type.
There are also s-types, the stony asteroids, and the m-types, the metal rich asteroids, like Psyche.
16 Psyche, is a fairly large asteroid, about 230 kilometres across. It is one of the largest in the asteroid belt - that area between Mars and Jupiter.
In the early Solar System, it was very chaotic with protoplanets and other material constantly being formed, swept-up, and destroyed.
It took millions of years for the various bits of planet and rock to be cleaned and sorted out into the defined planets, and their orbits, around the sun.
The main theory behind Psyche is that during its protoplanet (baby planet) stage, it crashed into something, with most of the outer, softer layers breaking off, and the heavier, more metal-rich core, being left behind.
Our core is too far down to reach, but studying Psyche can give us insight into our own planet's core.
The other reason for studying it are the metals themselves.
Psyche, we think, is rich in nickel, gold, platinum, and other elements (in some cases, it would take hundreds of thousands of years of mining on Earth to get the same amount).
It will tell us if they can be used for resources, and resources that are rare or hard to get on Earth.
Space resource utilisation will be key for future space exploration, just like ice on the moon and its potential for fuel.
Currently taking everything with us is too inefficient. Using material in space is more efficient, and the future.
Using metals to manufacture and repair satellites, build infrastructure, and change space into a true space economy.
It will be better than always bringing stuff up with us.
Bennu, on the other hand, is like a loose pile of rubble rather than one solid metal chunk like Psyche.
Bennu is not located in the asteroid belt, but part of the Apollo group - a group of asteroids that are in an orbit around the sun that regularly cross Earth's orbit.
These near-Earth asteroids are the ones we worry about.
The first samples have showed lots of hydrated clays on the asteroid - water contained in this rich, dark soil - almost like space mud.
It also contained lots of carbon in organic compounds and material.
Figuring out the composition will tell us how well we can send a mission and divert the asteroid, like NASA's DART mission tested last year.
It also can give insight into how to life on Earth may have started - with one idea being that the ingredients and spark of life came from an asteroid hitting Earth.
Two different asteroids giving us a glimpse into the past, and an exciting future.
- Brad E. Tucker is an astrophysicist and cosmologist at Mt Stromlo Observatory and the National Centre for the Public Awareness of Science at the ANU.
