A team of researchers affiliated with institutions in Australia, the U.S. and France has found evidence of relatively recent water movement in meteorites that only recently collided with the Earth. In their paper published in the journal Science, the group describes their study of carbonaceous chondrite (CC) meteorites that landed on the surface of the Earth within the past century and what they found.

A lot of scientists believe that the water present on Earth came from meteorites. This theory has been difficult to prove because the meteorites recovered to date do not contain water and because chemical reactions that might have involved comet-borne water occurred millions of years ago. In this new effort, the researchers took a look at the idea from another angle—they studied isotopes in meteorites that have landed on Earth over just the past century.

Prior research has suggested that most, if not all, CC meteorites were formed approximately 4.5 billion years ago as part of larger asteroids. To find out if recent arrivals might have evidence of a water history, the researchers looked at uranium and thorium distributions in samples—the former is water-soluble while the latter is not.

A cubesat, largely built by undergraduate students and scheduled to launch on Sunday, will explore the feasibility of a new propulsion method that could enable very small satellites to move around Earth's orbit without carrying fuel. This could pave the way for tiny satellites that stay in orbit for long periods and operate in swarms, monitoring storms and natural disasters, for example.

A cubesat is about the size of a loaf of bread, designed to hitch a ride into space with a major mission. Cubesats are low-cost ways to test out new technologies or enable students to get hands-on experience with space exploration. MiTEE is scheduled to fly from the Mojave Air and Space Port on Virgin Orbit's Launch Demo 2.

While Earth's atmosphere is much thicker on the ground, a scattering of air particles stretch all the way up to low Earth orbit—the territory of about 60 percent of Earth-orbiting satellites. Small satellites are more strongly affected by the drag of the upper atmosphere than large satellites, slowing their orbits and causing them to drop toward the Earth.

"These smaller spacecraft just don't last very long, maybe even days to weeks, or a few months, dependent upon how high they are," said Brian Gilchrist, a professor of electrical engineering and computer science, who supervised the team.