Mars may have once had a carbon cycle more favorable for life
Mars, one of our closest planetary neighbors, has fascinated people for hundreds of years, partly because it is so similar to Earth. It is about the same size, contains similar rocks and minerals, and is not too much farther out from the Sun. Because Mars and Earth share so many features, scientists have long wondered …
Pearl Young overcame barriers and ‘raised hell’ at NASA
Thirteen years before any other woman joined the National Advisory Committee for Aeronautics – or the NACA, NASA’s predecessor – in a technical role, a young lab assistant named Pearl Young was making waves in the agency. Her legacy as an outspoken and persistent advocate for herself and her team would pave the way for …
New theory explains how water first arrived on Earth
When Earth first formed, it was too hot to retain ice. This means all the water on our planet must have originated from extraterrestrial sources. Studies of ancient terrestrial rocks suggest liquid water existed on Earth as early as 100 million years after the Sun’s formation–practically “immediately” on an astrophysical timescale. This water, now over …
Why meteorites have less water than the asteroid bits returned by space probes
Much of what scientists know about the early solar system comes from meteorites – ancient rocks that travel through space and survive a fiery plunge through Earth’s atmosphere. Among meteorites, one type – called carbonaceous chondrites – stands out as the most primitive and provides a unique glimpse into the solar system’s infancy. The carbonaceous …
Extraordinary evidence needed to claim discovery of extraterrestrial life
The detection of life beyond Earth would be one of the most profound discoveries in the history of science. The Milky Way galaxy alone hosts hundreds of millions of potentially habitable planets. Astronomers are using powerful space telescopes to look for molecular indicators of biology in the atmospheres of the most Earth-like of these planets. …
Potential sign of life found on a distant planet and why many are still skeptical
A team of astronomers announced on April 16, 2025, that in the process of studying a planet around another star, they had found evidence for an unexpected atmospheric gas. On Earth, that gas – called dimethyl sulfide – is mostly produced by living organisms. In April 2024, the James Webb Space Telescope stared at the …
Gaia telescope ends mission to create 3D map of Milky Way
On Thursday 27 March, the European Space Agency (ESA) sent its last messages to the Gaia Spacecraft. They told Gaia to shut down its communication systems and central computer and said goodbye to this amazing space telescope. Gaia has been the most successful ESA space mission ever, so why did they turn Gaia off? What …
Building blocks of life found within asteroid Bennu
A bright fireball streaked across the sky above mountains, glaciers and spruce forest near the town of Revelstoke in British Columbia, Canada, on the evening of March 31, 1965. Fragments of this meteorite, discovered by beaver trappers, fell over a lake. A layer of ice saved them from the depths and allowed scientists a peek …
100 years ago Edwin Hubble settled astronomy’s ‘Great Debate’
A hundred years ago, astronomer Edwin Hubble dramatically expanded the size of the known universe. At a meeting of the American Astronomical Society in January 1925, a paper read by one of his colleagues on his behalf reported that the Andromeda nebula, also called M31, was nearly a million light years away – too remote …
Blue Origin’s New Glenn rockets to orbit − a feat 15 years in the making
Just past 2 a.m. Eastern time on Jan. 16, 2025, a new rocket blasted off from the Cape Canaveral Space Force Station in Florida. By reaching orbit, Blue Origin’s New Glenn rocket launch has marked a milestone for a commercial space company that has big ambitions. As a space policy expert, I see New Glenn’s …