Earth-Sized Planet Found At One of the Lightest Red Dwarfs

Artist’s conception of a rocky Earth-mass exoplanet like Wolf 1069 b orbiting a red dwarf star. If the planet has retained its atmosphere, chances are high that it would feature liquid water and habitable conditions over a wide area of its dayside. Image Credit: NASA/Ames Research Center/Daniel Rutter

Astronomers have found another Earth-sized planet. It’s about 31 light-years away and orbits in the habitable zone of a red dwarf star. It’s probably tidally locked, which can be a problem around red dwarf stars. But the team that found it is optimistic about its potential habitability.

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Hubble’s New View of the Tarantula Nebula

A snapshot of the Tarantula Nebula (also known as 30 Doradus) is the most recent Picture of the Week from the NASA/ESA Hubble Space Telescope. Image Credit: ESA/Hubble & NASA, C. Murray, E. Sabbi; Acknowledgment: Y. -H. Chu

The Tarantula Nebula, also called 30 Doradus, is the brightest star-forming region in our part of the galaxy. It’s in the Large Magellanic Cloud (LMC) and contains the most massive and hottest stars we know of. The Tarantula Nebula has been a repeat target for the Hubble since the telescope’s early years.

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Curiosity Finds Another Metal Meteorite on Mars

NASA's Curiosity Mars rover captured this image of an iron-nickel meteorite nicknamed "Cacao" on Jan, 28, 2023, the 3,725th Martian day, or sol, of the mission. Image Credit: NASA/JPL-Caltech/MSSS

MSL Curiosity is going about its business exploring Mars. The high-tech rover is currently exploring the sulphate-bearing unit on Mt. Sharp, the central peak in Mars’ Gale Crater. Serendipity placed a metal meteorite in its path.

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Hungry Black Hole was Already Feasting 800 Million Years After the Big Bang

Artist view of an active supermassive black hole. Credit: ESO/L. Calçada

Black holes swallow everything—including light—which explains why we can’t see them. But we can observe their immediate surroundings and learn about them. And when they’re on a feeding binge, their surroundings become even more luminous and observable.

This increased luminosity allowed astronomers to find a black hole that was feasting on material only 800 million years after the Universe began.

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This Binary System is Destined to Become a Kilonova

This is an artist’s impression of the first confirmed detection of a star system that will one day form a kilonova — the ultra-powerful, gold-producing explosion created by merging neutron stars. Image Credit: CTIO/NOIRLab/NSF/AURA/J. da Silva/Spaceengine/M. Zamani

Kilonovae are extraordinarily rare. Astronomers think there are only about 10 of them in the Milky Way. But they’re extraordinarily powerful and produce heavy elements like uranium, thorium, and gold.

Usually, astronomers spot them after they’ve merged and emitted powerful gamma-ray bursts (GRBs.) But astronomers using the SMARTS telescope say they’ve spotted a kilonova progenitor for the first time.

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How Can We Know if We’re Looking at Habitable exo-Earths or Hellish exo-Venuses?

How can astronomers tell exo-Earths and exo-Venuses apart? Polarimetry might be the key. Image Credits: NASA

The differences between Earth and Venus are obvious to us. One is radiant with life and adorned with glittering seas, and the other is a scorching, glowering hellhole, its volcanic surface shrouded by thick clouds and visible only with radar. But the difference wasn’t always clear. In fact, we used to call Venus Earth’s sister planet.

Can astronomers tell exo-Earths and exo-Venuses apart from a great distance?

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Astronomers Detect a Second Planet Orbiting Two Stars

Artist's impression of Kepler-16b, the first planet known to definitively orbit two stars - what's called a circumbinary planet. The planet, which can be seen in the foreground, was discovered by NASA's Kepler mission. Credit: NASA/JPL-Caltech/T. Pyle

Planets orbiting binary stars are in a tough situation. They have to contend with the gravitational pull of two separate stars. Planetary formation around a single star like our Sun is relatively straightforward compared to what circumbinary planets go through. Until recently, astronomers weren’t sure they existed.

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Don’t Bother Trying to Destroy Rubble Pile Asteroids

Detailed view of the rubble-pile asteroid 25143 Itokawa visited by the Japanese spacecraft Hayabusa in 2005. Credit: JAXA

The asteroids in our Solar System are survivors. They’ve withstood billions of years of collisions. The surviving asteroids are divided into two groups: monolithic asteroids, which are intact chunks of planetesimals, and rubble piles, which are made of up fragments of shattered primordial asteroids.

It turns out there are far more rubble pile asteroids than we thought, and that raises the difficulty of protecting Earth from asteroid strikes.

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It’s Already Hard Enough to Block a Single Star’s Light to See its Planets. But Binary Stars? Yikes

Binary stars are common and imaging their planets will be a challenge. How can astronomers block all that light so they can see the planets? This artist's illustration shows the eclipsing binary star Kepler 16, as seen from the surface of an exoplanet in the system. Image Credit: NASA

Detecting exoplanets was frontier science not long ago. But now we’ve found over 5,000 of them, and we expect to find them around almost every star. The next step is to characterize these planets more fully in hopes of finding ones that might support life. Directly imaging them will be part of that effort.

But to do that, astronomers need to block out the light from the planets’ stars. That’s challenging in binary star systems.

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Webb NIRISS Instrument has Gone Offline

Artist impression of the James Webb Space Telescope. Credit: ESA.

The JWST is having a problem. One of its instruments, the Near Infrared Imager and Slitless Spectrograph (NIRISS,) has gone offline. The NIRISS performs spectroscopy on exoplanet atmospheres, among other things.

It’s been offline since Sunday. January 15th due to a communications error.

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