astrobiology – Quanta Magazine

Doubts Grow About the Biosignature Approach to Alien-Hunting

Elise Cutts — Tue, 19 Mar 2024 13:50:35 +0000

In 2020, scientists detected a gas called phosphine in the atmosphere of an Earth-size rocky planet. Knowing of no way that phosphine could be produced except through biological processes, “the scientists assert that something now alive is the only explanation for the chemical’s source,” the New York Times reported. As “biosignature gases” go, the phosphine seemed like a home run. Until it wasn’t.

Source

Deep Beneath Earth’s Surface, Clues to Life’s Origins

Maya Wei-Haas — Thu, 04 Jan 2024 15:28:32 +0000

Near midnight on March 26, 1961, dark waters lapped at the hull of a converted naval barge as it queasily rocked in the Pacific Ocean. The ship had just arrived at this spot, some 240 kilometers off the Baja peninsula, after three days of fighting seas so rough the crew had lashed gear to the deck with heavy chains, “like a rogue elephant,” the novelist John Steinbeck, who was aboard the vessel...

Source

These Moons Are Dark and Frozen. So How Can They Have Oceans?

Robin George Andrews — Thu, 02 Nov 2023 14:49:29 +0000

For most of humankind’s existence, Earth was the only known ocean-draped world, seemingly unlike any other cosmic isle. But in 1979, NASA’s two Voyager spacecraft flew by Jupiter. Its moon Europa, a frozen realm, was decorated with grooves and fractures — hints that there might be something dynamic beneath its surface. “After Voyager, people suspected that Europa was weird and might have an ocean,”...

Source

An Explorer of Abyssal Depths Looks to Oceans on Other Worlds

Steve Nadis — Wed, 07 Jun 2023 14:04:43 +0000

As a boy growing up in Rochester, England, Chris German knew of his family’s strong maritime tradition, and he had no intention of continuing it. One of his grandfathers had served in the Royal Navy for much of his life, while the other had worked in the Chatham Naval Dockyard, as did German’s father and two uncles. Yet even though German attended a school founded in 1708 to train future ocean...

Source

A New Idea for How to Assemble Life

Philip Ball — Thu, 04 May 2023 14:40:01 +0000

Life on other worlds — if it exists — might be so alien as to be unrecognizable. There’s no guarantee that alien biology would use the same chemistries as on Earth, with familiar building blocks such as DNA and proteins. Scientists might even spot the signatures of such life forms without knowing they’re the work of biology. This problem is far from hypothetical. In April...

Source