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February 2nd, 2019
Near-Earth asteroid Bennu is 1,600 feet (500 meters) wide and contains hydrated minerals, according to scientists working on the NASA OSIRIS-REx spacecraft mission now underway. It could one day be mined for water by future explorers. Credit: NASA/Goddard/University of Arizona
A new study estimates that there are 440 to 1.3 billion U.S. tons of water that could be extracted from the minerals in near-Earth asteroids. That’s enough to fill between 160,000 and 480,000 Olympic-sized swimming pools.
A new study in the Journal of Geophysical Research: Planets, a publication of the American Geophysical Union, suggests there are between 26 and 80 hydrated near-Earth asteroids larger than a kilometer in diameter.
Of those, 8 to 26 of the asteroids are easier to get to than the surface of the Moon. The new study also estimates there are between 350 and 1,050 smaller hydrated objects easier to reach than the Moon.
Interplanetary space missions
“We know that there are minerals with water in them on asteroids. We know that from meteorites that have fallen to the ground.” said Andrew Rivkin of Johns Hopkins University Applied Physics Research Laboratory in Laurel, Maryland.
Rivkin is the lead author on the new paper — How Many Hydrated NEOs Are There? — with F. E. DeMeo of MIT.
As noted by Larry O’Hanlon, editor and online producer of the popular AGU Blogosphere, water in asteroids can provide hints about the nature of the early solar system, including clues about where Earth’s water and the Moon’s polar ice came from. It could also supply water and fuel to future interplanetary space missions, as noted by the authors of the new study.
Artist’s illustration of astronauts at an asteroid as well as other mining and transportation vehicles operating in space.
Credit: TransAstra Corporation & Anthony Longman
Mining companies
“Hydrated minerals are also of interest to asteroid mining companies, which hope to make their extraction and processing as the basis for their business,” explain Rivkin and DeMeo in their paper.
“For these reasons, we are interested in understanding how common hydrated asteroids are in the population of objects with orbits like the Earth’s. There are a few different ways we can make the calculation, but all of the estimates suggest that hydrated asteroids are more common than we would think from the pieces that fall to Earth, and that dozens of them are larger than 1 km in diameter and take less fuel for a round‐trip spacecraft than to the surface of the Moon,” the researchers explain.
Hot commodity
To get a better estimate would probably require a space telescope, like the James Webb Space Telescope, which is scheduled to launch in 2021, explains Rivkin.
Water is expected to be a hot commodity in space, as it is essential for human survival and can be used to propel spacecraft to other parts of the solar system, or to make propellant to refuel Earth-orbiting satellites.
Business plan for asteroid mining.
Credit: Joel Sercel/ICS Associates Inc. and TransAstra
To access the Journal of Geophysical Research: Planets paper – “How Many Hydrated NEOs Are There?” – go to:
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JE005584
Posted in Space News
