astronomy
14 posts
The TRAPPIST-1 System: Seven Earth-Sized Worlds and the Best Odds Yet for Life
In 2017, astronomers announced seven Earth-sized planets orbiting a small red dwarf star just 40 light-years away, with three in the habitable zone. TRAPPIST-1 has become the most studied planetary system beyond our own and the most compelling target for the search for life.
Jun 19, 2026 · 8 minThe Moons of Mars: Phobos, Deimos, and Their Mysterious Origins
Mars has two small, lumpy moons — Phobos and Deimos — that look nothing like our Moon and defy easy explanation. Phobos is slowly spiraling inward and will crash or disintegrate within 50 million years. A Japanese mission will bring back samples to settle their mysterious origins.
Jun 14, 2026 · 7 minRadio Astronomy and SETI: Listening for Signals from Other Civilizations
Radio waves are the obvious first medium for interstellar communication — they travel at the speed of light and pass through dust. In 1960, Frank Drake began the first systematic search for extraterrestrial intelligence. Sixty-five years later, the search continues with enormously more powerful instruments.
Jun 10, 2026 · 7 minBiosignatures: How Scientists Would Recognize Life on Another World
If life exists on another planet, how would we know? We cannot visit most exoplanets, but we can analyze the light filtering through their atmospheres. A living biosphere leaves chemical fingerprints that dead chemistry alone cannot produce.
Jun 3, 2026 · 7 minExtremophiles and What They Tell Us About Life Across the Cosmos
Life on Earth has colonized boiling volcanic springs, deep-ocean vents, Antarctic ice, acid lakes, and nuclear reactors. Organisms that thrive in these extremes — extremophiles — have transformed what astrobiologists consider possible on other worlds.
Jun 2, 2026 · 7 minHydrothermal Vents and the Leading Theory of How Life Began on Earth
Life on Earth began roughly 3.7 to 4 billion years ago, within a few hundred million years of the planet forming. The leading hypothesis today points to hydrothermal vents on the ocean floor, where chemical gradients could drive the first metabolic reactions.
Jun 1, 2026 · 7 minThe Giant Impact Hypothesis and How the Moon Was Born
The Moon is unusually large for a rocky planet's companion, shares Earth's orbital plane, and is remarkably similar in composition to Earth's outer layers. The leading explanation is violent: a Mars-sized body called Theia struck the young Earth.
May 31, 2026 · 7 minHow Our Solar System Formed from a Collapsing Molecular Cloud
About 4.6 billion years ago, a cloud of gas and dust in the Milky Way collapsed under its own gravity, forming the Sun and a spinning disc of material that eventually became every planet, moon, and asteroid in the solar system.
May 30, 2026 · 7 minSpace Weather and Auroras: How the Sun Shapes Our Magnetic Shield
The Sun constantly streams charged particles past Earth at hundreds of kilometers per second. When disrupted by solar flares or coronal mass ejections, this stream produces auroras, disrupts satellites, and in extreme cases can knock out power grids.
May 28, 2026 · 7 minPanspermia and the Possibility That Life Hitchhikes Between Worlds
Life on Earth could be a descendant of life from Mars. Or life on Mars, if we find it, could be a descendant of ours. The idea that biology can travel between planets — shielded inside rocks blasted off by asteroid impacts — is not science fiction. It is a serious scientific hypothesis with growing experimental support.
May 14, 2026 · 3 minFast Radio Bursts: The Deepest Mystery in Modern Astronomy
For a few milliseconds, a fast radio burst releases more energy than the Sun emits in three days. Then it is gone. Astronomers detected the first one in archival data in 2007; by 2020 we had identified hundreds, some of them repeating. We now know they come from across the universe, and in one case from within our own galaxy. We still do not fully understand what makes them.
May 13, 2026 · 4 minWhat a Type II Civilization's Megastructures Would Look Like to Our Telescopes
A civilization capable of harnessing the full output of its star would leave signatures visible across light-years: dimming patterns, heat signatures, unusual spectral features. The science of megastructure detection is a real field of astronomy, and a handful of star systems have already attracted attention.
May 2, 2026 · 4 minCould a Wandering Rogue Planet Ever Host Life or a Future Colony?
Astronomers believe there are more rogue planets — worlds flung out of their solar systems, drifting alone through the galaxy — than stars. Most are frozen and dark. A small fraction might not be. And some futurists have asked whether rogue planets could serve as generation-ship way stations or even destinations.
Apr 29, 2026 · 4 minThe Fermi Paradox and the Great Filter: Where Is Everyone?
The universe is 13.8 billion years old, contains hundreds of billions of galaxies, each with hundreds of billions of stars, and a significant fraction of those stars have Earth-like planets. Yet we see no signs of anyone else. The Fermi paradox is not a curiosity — it is one of the most important questions in science, and the leading answer is terrifying.
Apr 28, 2026 · 4 min