Astronomers Find a Sun-like Star Orbiting a Nearby Black Hole

Gaia BH1 is a Sun-like star co-orbiting with a black hole estimated at 10 times the Sun's mass. Credit: ESO/L. Calcada

In 1916, Karl Schwarzchild theorized the existence of black holes as a resolution to Einstein’s field equations for his Theory of General Relativity. By the mid-20th century, astronomers began detecting black holes for the first time using indirect methods, which consisted of observing their effects on surrounding objects and space. Since the 1980s, scientists have studied supermassive black holes (SMBHs), which reside at the center of most massive galaxies in the Universe. And by April 2019, the Event Horizon Telescope (EHT) collaboration released the first image ever taken of an SMBH.

These observations are an opportunity to test the laws of physics under the most extreme conditions and offer insights into the forces that shaped the Universe. According to a recent study, an international research team relied on data from the ESA’s Gaia Observatory to observe a Sun-like star with strange orbital characteristics. Due to the nature of its orbit, the team concluded that it must be part of a black hole binary system. This makes it the nearest black hole to our Solar System and implies the existence of a sizable population of dormant black holes in our galaxy.

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Mars Might Have Been Covered in Lakes in the Ancient Past

Artist's impression of Mars during the Noachian Era. Credit: Ittiz/Wikipedia Commons

Ever since robotic explorers began visiting the Red Planet during the 1960s and 70s, scientists have puzzled over Mars’ surface features. These included flow channels, valleys, lakebeds, and deltas that appear to have formed in the presence of water. Since then, dozens of missions have been sent to Mars to explore its atmosphere, surface, and climate to learn more about its warmer, wetter past. In particular, scientists want to know how long water flowed on the surface of Mars and whether it was persistent or periodic in nature.

The ultimate purpose here is to determine whether rivers, streams, and standing bodies of water existed long enough for life to emerge. So far, missions like Curiosity and Perseverance have gathered volumes of evidence that show how hundreds of large lakebeds once dotted the Martian landscape. But according to a new study by an international team of researchers, our current estimates of Mars’ surface water may be a dramatic understatement. Based on a meta-analysis of years’ worth of satellite data, the team argues that ancient lakes may have once been a very common feature on Mars.

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The First cry From a Brand new Baby Star

With its helical appearance resembling a snail’s shell, this reflection nebula seems to spiral out from a luminous central star in this new NASA/ESA Hubble Space Telescope image. The star in the centre, known as V1331 Cyg and located in the dark cloud LDN 981 — or, more commonly, Lynds 981 — had previously been defined as a T Tauri star. A T Tauri is a young star — or Young Stellar Object — that is starting to contract to become a main sequence star similar to the Sun. What makes V1331Cyg special is the fact that we look almost exactly at one of its poles. Usually, the view of a young star is obscured by the dust from the circumstellar disc and the envelope that surround it. However, with V1331Cyg we are actually looking in the exact direction of a jet driven by the star that is clearing the dust and giving us this magnificent view. This view provides an almost undisturbed view of the star and its immediate surroundings allowing astronomers to study it in greater detail and look for features that might suggest the formation of a verylow-mass object in the outer circumstellar disc.

The early universe was a much different place than our own, and astronomers do not fully understand how baby stars grew up in that environment. And while instruments like the James Webb Space Telescope will pierce back into the earliest epochs of star formation, we don’t always have to work so hard – there may be clues closer to home.

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A new way to Discover Planets? Astronomers Detect an Exoplanet by Seeing its Trojan Belts

Artist view of a planet and protoplanetary disk around a young star. Credit: M.Weiss/Center for Astrophysics | Harvard & Smithsonian

Although we have found thousands of exoplanets in recent years, we really only have three methods of finding them. The first is to observe a star dimming slightly as a planet passes in front of it (transit method). The second is to measure the wobble of a star as an orbiting planet gives it a gravitational tug (Doppler method). The third is to observe the exoplanet directly. Now a new study in the Astrophysical Journal Letters has a fourth method.

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Can Astronomers Predict Which Stars Are About to Explode as Supernovae?

In a recent study submitted to High Energy Astrophysical Phenomena, a team of researchers from Japan discuss strategies to observe, and possibly predict precursor signatures for an explosion from Local Type II and Galactic supernovae (SNe). This study has the potential to help us better understand both how and when supernovae could occur throughout the universe, with supernovae being the plural form of supernova (SN). But just how important is it to detect supernovae before they actually happen?

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Saturn Might Have Torn a Moon Apart to Make its Rings

Saturn's rings in all their glory. Image from the Cassini orbiter as Saturn eclipsed the Sun. Image Credit: By NASA / JPL-Caltech / Space Science Institute
Saturn's rings in all their glory. Image from the Cassini orbiter as Saturn eclipsed the Sun. Image Credit: By NASA / JPL-Caltech / Space Science Institute

Saturn is a world of surprises. The Voyager 1 and 2 flybys and later on, the Cassini mission, opened our collective eyes to intricate details in its rings and atmosphere. They also gave us up-close and personal looks at those amazing moons. But, one thing they didn’t show us was Saturn’s proposed moon Chrysalis. That’s because it doesn’t exist. Well, actually, it is there, but in the form of those dazzling rings.

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The History of the Sun is Written on the Moon

A 300 megapixel photo of our Sun, taken by using a specially modified telescope, compiling over 150,000 individual images. Credit and copyright: Andrew McCarthy.

If you want to learn about the history of the Sun, then look no further than the Moon. That’s the recommendation of a team of scientists who hope to harness future Artemis lunar missions to help understand the life history of our home star.

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