The Hubble Imaged Some Globular Clusters in an Unusual Place: Near the Milky Way’s Centre

Most globular clusters are found in the Milky Way's halo. But some, like the glittering globular cluster Terzan 12, are near the galactic centre. Image Credit: ESA/Hubble & NASA, R. Cohen (Rutgers University)

Our galaxy has about 200 Globular Clusters (GCs,) and most of them are in the galaxy’s halo. Astronomers think most GCs were taken from dwarf galaxies and merged with the Milky Way due to the galaxy’s powerful gravity. That explains why so many of them are on the outskirts of the galaxy. But they’re not all in the halo. Some are towards the Milky Way’s galactic bulge. What are globular clusters doing there?

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JWST Accidentally Found 21 Brown Dwarfs

This artist's conception illustrates the brown dwarf named 2MASSJ22282889-431026, observed by NASA's Hubble and Spitzer space telescopes. Brown dwarfs are more massive and hotter than planets but lack the mass required to become stars. Image credit: NASA
This artist's conception illustrates the brown dwarf named 2MASSJ22282889-431026, observed by NASA's Hubble and Spitzer space telescopes. Brown dwarfs are more massive and hotter than planets but lack the mass required to become stars. Image credit: NASA

When you launch humanity’s most powerful telescope, you expect results. The JWST has delivered excellent results by detecting ancient galaxies, identifying chemicals in exoplanet atmospheres, and peering into star-forming regions with more detail and clarity than any other telescope.

But every time a new telescope is about to enter service, astronomers tell us they’re excited not only about the expected results but also about the surprising results. And like other telescopes, the JWST has also delivered some surprises. While going about its business, the JWST has discovered 21 brown dwarfs.

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A Black Hole Nibbles on a Star Every 22 Days, Slowly Consuming it

A star is ripped apart by a black hole. Credit: Mark Garlick

Astronomers working with NASA’s Neil Gehrels Swift Observatory have spotted something unusual. The observatory’s X-Ray Telescope (XRT) has captured emissions from a supermassive black hole (SMBH) in a galaxy about 500 million light-years away. The black hole is repeatedly feeding on an unfortunate star that came too close.

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A Last-Minute Addition to the Solar Orbiter Allows it to See More Deeply into the Sun’s Atmosphere

A clever astronomer made a last minute hack to the Solar Orbiter's Extreme Ultraviolet Imager, allowing it to capture better images. Image Credit: ESA & NASA/Solar Orbiter/EUI Team; F. Auchère et al (2023); Solar disc: NASA/STEREO

Spacecraft instruments are highly specialized and can take years to design, build, and test. But a last-minute hack to one of the instruments on the ESA’s Solar Orbiter has allowed the spacecraft to take some difficult observations it would otherwise have been unable to take.

It’s all because of one astronomer and an instrument door.

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As Night Falls, India’s Lunar Lander/Rover Goes to Sleep. Probably Forever

India's Pragyan lunar rover has been put into sleep mode after the end of its first lunar day. There's still a chance it could reawaken, but there's no guarantee. Image Credit: ISRO

India’s Chandrayaan-3 mission delivered its Vikram lander and Pragyan rover to the lunar surface on August 23rd. Now, as the lunar day ends two weeks later, the rover’s mission may be over. The Indian Space Research Organisation (ISRO) has put Pragyan into sleep mode.

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TESS Finds a Planet That Takes 482 Days to Orbit, the Widest it’s Seen so Far

An artist's rendition of the two planets and star in the TOI-4600 system. One of them has the longest orbit of any planet yet found by TESS. Image Credit: Tedi Vick

We’re rapidly learning that our Solar System, so familiar to us all, does not represent normal.

A couple of decades ago, we knew very little about other solar systems. Astronomers had discovered only a handful of exoplanets, especially around pulsars. But that all changed in the last few years.

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JWST Gazes into the Dark Molecular Clouds at the Heart of the Milky Way

The Central Molecular Zone; the Heart of the Milky Way. Image Credit: Henshaw / MPIA

There’s an unusual object near the Milky Way’s heart that astronomers call “The Brick.” It’s a massive cloud of gas called an infrared dark cloud (IDC). The Brick is dense and turbulent like others of its type, but for some reason, it shows few signs of star formation.

Why?

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NASA Satellite Spots the Crash Site for Luna 25

Luna 25's crash site near Pontécoulant G crater. Image Credit: NASA’s Goddard Space Flight Center/Arizona State University

Poor Russia. They can’t seem to get much right. Their most recent failure is their Luna 25 spacecraft. It was supposed to land near the Moon’s south pole but instead crashed into the surface on August 19th.

Now NASA’s Lunar Reconnaissance Orbiter (LRO) has spotted Luna 25’s final resting place.

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Is Anyone Planning for Diplomacy with an Extraterrestrial Civilization?

Artist impression of an alien civilization. Image credit: CfA

Imagine we detect an interstellar object entering our Solar System. At first, astronomers think it’s just another natural interloper like Oumuamua or comet Borisov. We’re warming up to the idea of visitors from other parts of the galaxy, though they’ve been inanimate so far.

But then, what if it becomes clear that something’s different about this visitor? What if it moves unnaturally or somehow behaves purposefully? What if it takes up a stable orbit somewhere? What if, as we gather more evidence, it becomes clear that it’s a probe of some sort sent to us intentionally? What if it communicates with us?

Suddenly, as if thrust into a science fiction plot, humanity is in a totally different situation. What do we do?

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Did this Supernova Explode Twice?

Artist view of a binary system before a type Ia supernova. Credit: Adam Makarenko/W. M. Keck Observatory

All supernovae are exploding stars. But the nature of a supernova explosion varies quite a bit. One type, named Type 1a supernovae, involves a binary star where one of the pair is a white dwarf. And while supernovae of all types usually involve a single explosion, astronomers have found something that breaks that mould: A Type 1a supernova that may have detonated twice.

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