Astronomers Have Found the Star/Exoplanet Combo That’s the Best Twin to the Sun/Earth

An artist's illustration of TOI 700d, an Earth-size exoplanet that TESS found in its star's habitable zone. Image Credit: NASA

At times, it seems like there’s an indundation of announcements featuring discoveries of “Earth-like” planets. And while those announcements are exciting, and scientifically noteworthy, there’s always a little question picking away at them: exactly how Earth-like are they, really?

After all, Earth is defined by its relationship with the Sun.

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Gamma Rays Detected Coming From the Crab Nebula

Crab Nebula (Credit:NASA, ESA and Allison Loll/Jeff Hester (Arizona State University). Acknowledgement: Davide De Martin (ESA/Hubble))

Most people with any interest in astronomy know about the Crab Nebula. It’s a supernova remnant in the constellation Taurus, and its image is all over the place. Google “Hubble images” and it’s right there with other crowd favorites, like the Pillars of Creation.

The Crab Nebula is one of the most-studied objects in astronomy. It’s the brightest source of gamma rays in the sky, and that fact is being used to establish the function of a new telescope called the Schwarschild-Couder Telescope.

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Much of the Lithium Here on Earth Came from Exploding White Dwarf Stars

A classical novae contains a white dwarf, and a larger companion star in orbit around it. The white dwarf attracts gas from its companion, leading to a massive explosion. Illustration Credit: David Hardy

The Big Bang produced the Universe’s hydrogen, helium, and a little lithium. Since then, it’s been up to stars (for the most part) to forge the rest of the elements, including the matter that you and I are made of. Stars are the nuclear forges responsible for creating most of the elements. But when it comes to lithium, there’s some uncertainty.

A new study shows where much of the lithium in our Solar System and our galaxy comes from: a type of stellar explosion called classical novae.

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A New Telescope is Ready to Start Searching for Answers to Explain Dark Energy

An illustration of cosmic expansion. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

Back in 2015, construction began on a new telescope called the Dark Energy Spectroscopic Instrument (DESI). Later this year, it will begin its five-year mission. Its goal? To create a 3D map of the Universe with unprecedented detail, showing the distribution of matter.

That detailed map will allow astronomers to investigate important aspects of cosmology, including dark energy and its role in the expansion of the Universe.

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Supermassive Black Holes Grew by Consuming Gas and Entire Stars

This artist’s impression of a supermassive black hole and accretion disk, along with a relativistic jet emanating from its poles. Credit & ©: ESO/L. Calçada

Where do they come from, those beguiling singularities that flummox astrophysicists—and the rest of us. Sure, we understand the processes behind stellar mass black holes, and how they form from the gravitational collapse of a star.

But what about the staggering behemoths at the center of galaxies, those supermassive black holes (SMBH) that can grow to be billions of times more massive than our Sun?

How do they get so big?

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Interstellar Oumuamua Was a Dark Hydrogen Iceberg

Artist’s impression of the first interstellar asteroid/comet, "Oumuamua". This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Credit: ESO/M. Kornmesser

When Canadian astronomer Robert Weryk discovered `Oumuamua passing through our Solar System with the Pan-STARRS telescope, in October 2017, it caused quite a stir. It was the first interstellar object we’d ever seen coming through our neighbourhood. The excitement led to speculation: what could it be?

There was lots of fun conjecture on its origins. Was it an alien spacecraft? A solar sail? Or something more prosaic?

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Finally! Mars InSight’s Mole is Now Underground

On June 4th NASA reported that the Mole is finally making some headway. But the instrument is not producing any science yet. Image Credit: NASA/DLR/JPL

It looks like the InSight Lander’s Mole instrument is making some progress. After months of perseverance, the team operating the instrument has succeeded in getting the Mole at least some distance into the ground.

That’s a victory in itself, considering all the setbacks there’ve been. But it’s too soon to celebrate: there’s quite a ways to go before the Mole can deliver any science.

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Astronomers Find the Source of the Huge Bubbles of Gas Flowing Out of the Milky Way, Still No Idea What Caused Them

Astronomers used the WHAM telescope to measure huge outflows of gas extending from the Milky Way’s center known as the Fermi Bubbles. They were able to measure the velocity, density and pressure of the gas for the first time, confirming and extending previous measurements made by using a distant quasar as a light source to look through and measure the gas. IMAGE BY DHANESH KRISHNARAO AND NASA

There’s an unusual paradox hampering research into parts of the Milky Way. Dense gas blocks observations of the galactic core, and it can be difficult to observe in visible light from our vantage point. But distant galaxies don’t always present the same obstacles. So in some ways, we can observe distant galaxies better than we can observe our own.

In order to gain a better understanding of the Galactic Center (GC) and the Interstellar Medium (ISM), a team of astronomers used a telescope called the Wisconsin H-Alpha Mapper (WHAM) to look into the core of the Milky Way in part of the optical light spectrum.

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Evidence that Mars Used to Have a Ring

An illustration of Mars with a debris ring. Image Credit: SETI

Mars only has two moons: Phobos and Deimos. They’re strange, for moons, little more than lumpy, potato-shaped chunks of rock. They’re much too small for self-gravitation to have made them round. And one of them, Deimos, has an unusually tilted orbit.

What does that slight tilt tell us about Deimos? About Mars?

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About 3.5 Million Years Ago, a Stream of Gas Outside the Milky Way Would Have Lit Up the Night Sky

An illustration of our hominid ancestors, likely Australopithecus, walking at night, under the lit up stream of gas about 3.5 million years ago. Image Credit: NASA, ESA, G. Cecil (UNC, Chapel Hill), and J. DePasquale (STScI)

It’s a truism to point out that modern humans have only been around for the blink of an eye, relative to the age of the Universe. But the Universe was an active place long before we were around to observe all of that activity. And about 3.5 million years ago, it’s possible—if only remotely—that our ancient ancestors noticed something change in the night sky.

Would it have stirred something inside them? Impossible to know.

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