This is it! Meet the Supermassive Black Hole at the Heart of the Milky Way

This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientist suggests its accretion disk may be more elongated than shown in this image. Image Credit: EHT
This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientist suggests its accretion disk may be more elongated than shown in this image. Image Credit: EHT

On April 10th, 2019, the international consortium known as the Event Horizon Telescope (EHT) announced the first-ever image of a supermassive black hole (SMBH). The image showed the bright disk surrounding the black hole at the center of the M87 galaxy (aka. Virgo A). In 2021, they followed up on this by acquiring an image of the core region of the Centaurus A galaxy and the radio jet emanating from it. Earlier this month, the European Southern Observatory (ESO) announced that the EHT would be sharing the results from its latest campaign – observations of Sagittarius A*!

This supermassive black hole resides at the center of the Milky Way Galaxy, roughly 27,000 light-years from Earth, 44 million km (27.34 million mi) in diameter, and has a mass of 4.31 million Suns. The campaign’s results were shared in an ESO press release and a series of live-streamed press conferences worldwide, including the ESO Headquarters in Munich, Germany. The team’s results (which were shared in six papers) were also published today in a special issue of The Astrophysical Journal Letters.

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We’ve Now Seen Planet-Forming Disks Around Hundreds of Young Stars. What Do They Tell Us?

ALMA's high-resolution images of nearby protoplanetary disks, which are results of the Disk Substructures at High Angular Resolution Project (DSHARP). The observatory is often used to look for planet birth clouds like these and the one around HD 169142. Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello
ALMA's high-resolution images of nearby protoplanetary disks, which are results of the Disk Substructures at High Angular Resolution Project (DSHARP). The observatory is often used to look for planet birth clouds like these and the one around HD 169142. Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello

Is our Solar System comparable to other solar systems? What do other systems look like? We know from exoplanet studies that many other systems have hot Jupiters, massive gas giants that orbit extremely close to their stars. Is that normal, and our Solar System is the outlier?

One way of addressing these questions is to study the planet-forming disks around young stars to see how they evolve. But studying a large sample of these systems is the only way to get an answer. So that’s what a group of astronomers did when they surveyed 873 protoplanetary disks.

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Our Complete Guide to This Weekend’s Total Lunar Eclipse

Becke eclipse
A mosaic of the # total lunar eclipse. Image credit and copyright: Christopher Becke.

Don’t miss one of the top astronomical events for 2022: Sunday night’s total lunar eclipse.

The first eclipse season of 2022 reaches its climax this coming weekend, with a fine total lunar eclipse transpiring on Sunday night into Monday morning. All of South America and most of North America will see the eclipse in its entirety, while Alaska and western Canada will see totality underway at moonrise, and western Europe will see the reverse at moonset near dawn.

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InSight Just Detected a Record-breaking Marsquake: Magnitude 5!

This spectrogram shows the largest quake ever detected on another planet. The marsquake struck the Red Planet on May 4 , 2022 and measured magnitude 5 . Courtesy NASA/JPL-Caltech/ETH/Zurich.
This spectrogram shows the largest quake ever detected on another planet. The marsquake struck the Red Planet on May 4 , 2022 and measured magnitude 5 . Courtesy NASA/JPL-Caltech/ETH/Zurich.

May 4th is unofficially known in sci-fi circles as Star Wars Day (“May the Fourth Be With You”) here on Earth. But, on another planet, far, far away, the date is now infamous to one of its robotic inhabitants. That’s the day the Mars InSight lander felt one of the strongest marsquakes ever to hit that world. It registered magnitude 5 and was the latest 1,313 quakes the lander detected since it arrived on Mars in 2018. InSight scientists are still analyzing the data to figure out exactly where on Mars the quake struck, and what may have caused it.

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‘The Clocks are Telling Lies:’ A New Book from Universe Today Writer Scott Alan Johnston

Scott Alan Johnston (that’s me!) joined the Universe Today team just over a year ago. Since then, I’ve written over 50 space news stories for the website – time flies when you’re having fun! But when I’m not writing articles here on Universe Today, I’m a historian of science, and I recently released a new book about the history of timekeeping.

Have you ever wondered why we tell time the way we do? Well, history buffs, come along for a journey:

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Martian Dust is Starting to Darken Ingenuity’s Solar Panels

This image of NASA’s Ingenuity Mars Helicopter was taken by the Mastcam-Z instrument of the Perseverance rover on June 15, 2021, the 114th Martian day, or sol, of the mission. The location, "Airfield D" (the fourth airfield), is just east of the "Séítah" geologic unit. Credits: NASA/JPL-Caltech/ASU/MSSS.

Like every solar-panel-powered vehicle on Mars, maintaining electrical power always becomes an issue at some point in the mission. Last week, mission controllers at the Jet Propulsion Laboratory lost contact with the Ingenuity Mars Helicopter. While they were able to re-establish communications, which is done through the Perseverance rover, engineers know that keeping Ingenuity’s batteries charged is going to be increasingly difficult as the dark winter is on the way to Jezero Crater.

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These are the Best Places to Search for Habitable Exomoons

An artist's conception of a potentially-habitable exomoon. It seems reasonable that exoplanets have exomoons, and now we're going to look for them. Credit: NASA

Our Solar System contains eight planets and more than 200 moons. The large majority of those moons have no chance of being habitable, but some of them—Europa and Enceladus, for example—are strong candidates in the search for life.

Is it the same in other solar systems?

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Artemis 1 Probably won't Launch Until August

The Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida, the right-hand center aft booster segment for Artemis I is stacked on the mobile launcher for the Space Launch System (SLS) on Jan. 7, 2021. Photo credit: NASA/Kim Shiflett

On March 17th, the Artemis I mission rolled out of the Vehicle Assembly Building (VLB) and was transferred to Launch Complex 39B at the NASA Kennedy Space Center in Florida. This was the first time that a fully-stacked Space Launch System (SLS) and Orion spacecraft were brought to the launchpad in preparation for a “wet dress rehearsal.” To mark the occasion, NASA released a video of the event that featured a new song by Pearl Jam’s Eddie Vedder (“Invincible”).

Unfortunately, technical issues forced ground controllers to scrub the dress rehearsal repeatedly and return the Artemis I to the VLB on April 26th. This was followed by reports that these issues were addressed and that Artemis I rocket would return to LC 39B by early- to mid-June. Meanwhile, an official NASA statement (issued on Thursday, May 8th) says that the official launch of the mission is not likely to take place until August at the earliest.

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The Tonga Eruption Reached Space!

The GOES-17 satellite captured images of an umbrella cloud generated by the underwater eruption of the Hunga Tonga-Hunga Ha’apai volcano on Jan. 15, 2022. The Tonga eruption sent crescent-shaped bow shock waves through the atmosphere, as well as numerous lightning strikes.
Credits: NASA Earth Observatory image by Joshua Stevens using GOES imagery courtesy of NOAA and NESDIS
What a massive volcanic eruption looks like from space. The GOES-17 satellite captured images of an umbrella cloud generated by the underwater eruption of the Hunga Tonga-Hunga Ha’apai volcano on Jan. 15, 2022. The Tonga eruption sent crescent-shaped bow shock waves through the atmosphere, as well as numerous lightning strikes. Credits: NASA Earth Observatory image by Joshua Stevens using GOES imagery courtesy of NOAA and NESDIS

Volcanic eruptions do more than send lava and clouds of noxious gas across the landscape, and trigger tsunamis and sonic booms. Sometimes they reach for space! In the case of the January 2022 underwater eruption of Tonga-Hunga Ha’apai, it sent a pressure wave through all altitudes of Earth’s atmosphere. Seismic stations and weather stations around the world (including the one on my front deck) recorded that wave as it boomeranged around the planet! And, there was another surprising result. The Tonga eruption breached Earth’s atmosphere and caused space-weather-like disruptions at the edge of space.

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Mars' Carbon Dioxide Glaciers are on the Move

Mars’ south polar ice cap. Credit: ESA / DLR / FU Berlin /

In 1666, famed Italian astronomer and mathematician Giovanni Cassini (the man who discovered four of Saturn’s largest moons) observed the Martian polar ice caps for the first time. However, it was not until the late-18th century, when Sir William Herschel recorded his own observations, that the connection to Earth’s own ice caps was established. In his subsequent treatise, “On the remarkable appearances at the polar regions on the planet Mars” (1784), noted how the southern cap grew and shrunk due to seasonal changes.

With the development of modern telescopes and robotic explorers, scientists have learned a great deal more about these polar deposits. In 2011, they learned that unlike the northermost ice sheet, the southern cap is largely composed of frozen carbon dioxide (aka. “dry ice”). According to new research led by the Planetary Science Institute (PSI), glaciers of carbon dioxide ice have been moving and carving features in the southern polar region for more than 600,000 years – and are on the move right now!

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