The Stellar Demolition Derby in the Centre of the Galaxy

This illustration shows stars orbiting close to the Milky Way's central supermassive black hole. The black hole accelerates stars nearby and sends them crashing into one another. Credit: ESO/L. Calçada/Spaceengine.org

The region near the Milky Way’s centre is dominated by the supermassive black hole that resides there. Sagittarius A*’s overwhelming gravity creates a chaotic region where tightly packed, high-speed stars crash into one another like cars in a demolition derby.

These collisions and glancing blows change the stars forever. Some become strange, stripped-down, low-mass stars, while others gain new life.

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A New Map Shows the Universe’s Dark Energy May Be Evolving

This image shows a slice of the 3D map of galaxies collected in the first year of the Dark Energy Spectroscopic Instrument (DESI) Survey. Earth is at the tip, with the furthest galaxies plotted at distances of 11 billion light-years. Each point represents one galaxy. This version of the DESI map includes 600,000 galaxies — less than 0.1% of the survey's full volume. Image Credit: DESI Collaboration/NOIRLab/NSF/AURA/R. Proctor

At the Kitt Peak National Observatory in Arizona, an instrument with 5,000 tiny robotic eyes scans the night sky. Every 20 minutes, the instrument and the telescope it’s attached to observe a new set of 5,000 galaxies. The instrument is called DESI—Dark Energy Survey Instrument—and once it’s completed its five-year mission, it’ll create the largest 3D map of the Universe ever created.

But scientists are getting access to DESI’s first data release and it suggests that dark energy may be evolving.

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A New Tabletop Experiment to Search for Dark Matter

Astronomers are getting a new tool to help them in the hunt for Dark Matter. This is a rendering of the BREAD design, which stands for Broadband Reflector Experiment for Axion Detection. The ‘Hershey’s Kiss’-shaped structure funnels potential dark matter signals to the copper-colored detector on the left. The detector is compact enough to fit on a tabletop. Image courtesy BREAD Collaboration

What is Dark Matter? We don’t know. At this stage of the game, scientists are busy trying to detect it and map out its presence and distribution throughout the Universe. Usually, that involves highly-engineered, sophisticated telescopes.

But a new approach involves a device so small it can sit on a kitchen table.

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Perseverance Finds its Dream Rock

This Martian rock, named Bunsen Peak, contains minerals that formed in the presence of water. On Earth, these water-deposited carbonate minerals are good at preserving ancient organic material. Image Credit: NASA/JPL-Caltech

If there’s a Holy Grail on Mars, it’s probably a specific type of rock: A rock so important that it holds convincing clues to Mars’ ancient habitability.

Perseverance might have just found it.

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The Large Magellanic Cloud isn’t Very Metal

This image shows the Large and Small Magellanic Clouds in the sky over the ESO's Paranal Observatory and the four telescopes of the VLT. Image Credit: By ESO/J. Colosimo - http://www.eso.org/public/images/potw1511a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=38973313

The Large Magellanic Cloud (LMC) is the Milky Way’s most massive satellite galaxy. Because it’s so easily observed, astronomers have studied it intently. They’re interested in how star formation in the LMC might have been different than in the Milky Way.

A team of researchers zeroed in on the LMC’s most metal-deficient stars to find out how different.

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How Animal Movements Help Us Study the Planet

This map shows how elephants moved across Kruger National Park in South Africa over one year. Image Credit: Thaker, M., et al. (2019)

Scientists have been underutilizing a key resource we can use to help us understand Earth: animals. Our fellow Earthlings have a much different, and usually much more direct, relationship with the Earth. They move around the planet in ways and to places we don’t.

What can their movements tell us?

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Want to Leave the Solar System? Here’s a Route to Take

A future interstellar probe mission aims to travel beyond the heliosphere to the local interstellar medium to understand where our home came from and where it is going. Credit: John Hopkins Applied Physics Laboratory.

The edge of the Solar System is defined by the heliosphere and its heliopause. The heliopause marks the region where the interstellar medium stops the outgoing solar wind. But only two spacecraft, Voyager 1 and Voyager 2, have ever travelled to the heliopause. As a result, scientists are uncertain about the heliopause’s extent and its other properties.

Some scientists are keen to learn more about this region and are developing a mission concept to explore it.

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Curiosity has Reached an Ancient Debris Channel That Could Have Been Formed by Water

The steep path NASA’s Curiosity Mars rover took to reach Gediz Vallis channel is indicated in yellow in this visualization made with orbital data. At lower right is the point where the rover veered off to get an up-close look at a ridge formed long ago by debris flows from higher up on Mount Sharp. NASA/JPL-Caltech/UC Berkeley

Like a pilgrim seeking wisdom, NASA’s MSL Curiosity has been working its way up Mt. Sharp, the dominant central feature in Gale Crater. Now, almost 12 years into its mission, the capable rover has reached an interesting feature that could tell them more about Mars and its watery history. It’s called the Gediz Vallis channel.

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Where Are All These Rogue Planets Coming From?

An artist's illustration of a rogue planet, dark and mysterious. Image Credit: NASA

There’s a population of planets that drifts through space untethered to any stars. They’re called rogue planets or free-floating planets (FFPs.) Some FFPs form as loners, never having enjoyed the company of a star. But most are ejected from solar systems somehow, and there are different ways that can happen.

One researcher set out to try to understand the FFP population and how they came to be.

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The Hubble Aims Its Powerful Ultraviolet Eye at Super-Hot Stars

This is a Hubble Space Telescope image of a star-forming region containing massive, young, blue stars in 30 Doradus, the Tarantula Nebula. Located within the Large Magellanic Cloud, this is one of the regions observed by a newly-completed survey named ULLYSES. Image Credit: NASA, ESA, STScI, Francesco Paresce (INAF-IASF Bologna), Robert O'Connell (UVA), SOC-WFC3, ESO

Some stars are so massive and so energetic that they’re a million times brighter than the Sun. This type of star dominated the early Universe, playing a key role in its development and evolution. The first of its kind are all gone now, but the modern Universe still forms stars of this type.

These hot, blue stars emit powerful ultraviolet energy that the Hubble can detect from its perch in Low-Earth Orbit.

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