exoplanets

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Exoplanets Around Barnard's Star Are Uninhabitable
2 months ago
- Barnard's Star is the closest single star system to Earth, located less than 6 light-years away, and hosts four confirmed exoplanets discovered between 2024 and 2025.
- These exoplanets have masses between Earth and Mars but are likely uninhabitable due to high levels of periclase (magnesium oxide) that prevent water storage.
- The planets orbit extremely close to their star (1% to 4% of Earth-Sun distance), are tidally locked, and lost their atmospheres after about 2 billion years due to stellar radiation.
- Despite instability risks, the three inner planets maintain orbital resonance (9:12:16) which stabilizes the system.
- The research, published in Monthly Notices of the Royal Astronomical Society, links stellar and planetary composition to assess habitability, aiding future missions like PLATO.
NASA's Roman Telescope vs. Webb: the telescope that will map a billion galaxies
2 months ago
- The Nancy Grace Roman Space Telescope will launch on August 30, 2026, from Kennedy Space Center on a SpaceX Falcon Heavy.
- Roman features a 2.4-meter mirror, similar to Hubble's, but with a camera 100 times wider, enabling surveys 1,000 times faster than Hubble.
- It will map over a billion galaxies and find up to 200,000 exoplanets, focusing on dark energy, dark matter, and planetary demographics.
- Roman includes an active coronagraph that can detect planets 100 million times fainter than their stars, a technology demonstration for future missions.
- The telescope will generate about 1.4 TB of data daily, with open access to all astronomers immediately after calibration.
- Roman will work synergistically with the James Webb Space Telescope, using wide surveys to identify targets for Webb's deep follow-up observations.
Will We Ever Find Alien Civilizations?
2 months ago
- The search for alien civilizations is a long-standing question, but remains unanswered despite occasional intriguing signals.
- David Kipping uses statistical approaches to assess habitable worlds and biosignatures, rather than chasing individual detections.
- Exomoons are considered a promising place to search for life due to their potential habitability and influence on planets.
- The Drake equation organizes the search for intelligent life but has limitations due to unknown parameters; a birth-death model simplifies it to a birth-to-death ratio.
- Statistical analysis suggests the universe is either crowded with civilizations or very lonely, with current observations favoring loneliness for technological life.
- SETI (Search for Extraterrestrial Intelligence) has not found clear signals, suggesting technological civilizations may be rare, though simpler life could still be common.
- UFO claims lack scientific rigor due to unknown false positive rates and reproducibility issues, making them difficult to assess.
- Exomoons can confound biosignature detection in exoplanet atmospheres, as mixed signals from moons and planets may lead to false positives.
- James Webb Space Telescope is advancing exoplanet characterization, but detecting unambiguous biosignatures remains challenging; an A/B testing method is proposed to differentiate life signals.
- The search for alien life enriches human curiosity and perspective, akin to art or poetry, and can inspire global cooperation and humility.
Large planets lighter than cotton candy
2 months ago
- Astronomers discovered two exceptionally low-density exoplanets, comparable in size to Jupiter but lighter than cotton candy.
- These 'super-puffs' orbit a star 1,110 light-years away in the Volans constellation and have densities likened to shaving foam.
- The planets are likely composed of hydrogen and helium, with potential white or blue coloration, pending confirmation by the Webb Telescope.
- Their orbits are unusually long, taking 139 and 232 days respectively, and they are rare, with fewer than 40 such planets confirmed among nearly 6,300 exoplanets.
- The discovery challenges existing models of planet formation, representing a cosmic puzzle for astronomers to solve.

exoplanets

Exoplanets Around Barnard's Star Are Uninhabitable

NASA's Roman Telescope vs. Webb: the telescope that will map a billion galaxies

Will We Ever Find Alien Civilizations?

Large planets lighter than cotton candy