Universe Today

October 3, 2023October 3, 2023 by Brian Koberlein

Astronomers Watched a Massive Star Just… Disappear. Now JWST Might Have Some Answers

Illustration of how a failed supernova can become a black hole. Credit: NASA/ESA/P. Jeffries (STScI)

In 2009 a giant star 25 times more massive than the Sun simply…vanished. Okay, it wasn’t quite that simple. It underwent a period of brightening, increasing in luminosity to a million Suns, just as if it was ready to explode into a supernova. But then it faded rather than exploding. And when astronomers tried to see the star, using the Large Binocular Telescope (LBT), Hubble, and the Spitzer space telescope, they couldn’t see anything.

The star, known as N6946-BH1, is now considered a failed supernova. The BH1 in its name is due to the fact that astronomers think the star collapsed to become a black hole rather than triggering a supernova. But that has been conjecture. All we’ve known for sure is that it brightened for a time then grew too dim for our telescopes to observe. But that has changed, thanks to the James Webb Space Telescope (JWST).

October 2, 2023October 2, 2023 by Carolyn Collins Petersen

New Horizons is Funded Through the Decade. Enough to Explore Another Kuiper Belt Object

Since its last flyby, of the Kuiper Belt object Arrokoth, the New Horizons mission has been exploring objects in the Kuiper Belt as well as performing heliospheric and astrophysical observations. Courtesy: Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute//Roman Tkachenko

The ongoing saga of the New Horizons mission—will it get truncated and its science team disbanded?—may have some resolution. Dr. Nicky Fox, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters announced last Friday that mission operations will continue until at least the end of the decade.

October 2, 2023October 2, 2023 by Brian Koberlein

It's Confirmed. M87's Black Hole is Actually Spinning

Schematic representation of the tilted accretion disk model. Credit: Cui et al. (2023), Intouchable Lab@Openverse and Zhejiang Lab

Fifty-five million light-years away, in the galaxy known as M87, lies a supermassive black hole. It is a powerfully active black hole with a mass of 6.5 billion Suns, and in 2019 it was the first black hole to be imaged directly. The radio image captured by the Event Horizon Telescope (EHT) shows a halo of ambient light warped by the black hole’s gravity and directed our way. On one side of the halo, the light is brighter, which according to general relativity is due to the rotation or spin of the black hole. It was the first direct confirmation that the black hole rotates. A new study published in Nature has given us more rotational evidence.

October 1, 2023October 1, 2023 by Andy Tomaswick

What’s the Link Between Gamma Ray Bursts and Supernovae? It Might Be Binary Stars

Gamma-ray bursts (GRBs) are some of the most violent events in the universe. Some have a power output equivalent to all of the other stars in the observable universe, at least in the spectrum of gamma rays. But we know very little about them. A new paper from researchers on an interdisciplinary team from seven countries puts forth a new theory about how at least one type of GRB happens – when a binary of two specific types of stars collapses and forms a black hole.

October 1, 2023October 1, 2023 by Matt Williams

Astronomers are Working to Put a Radio Telescope on the Far Side of the Moon by 2025

This artist’s rendering shows LuSEE-Night atop the Blue Ghost spacecraft scheduled to deliver the experiment to the far side of the moon. Credit: Firefly Aerospace

The Moon will be a popular destination for space programs worldwide in the coming years. By 2025, NASA’s Artemis III mission will land the first astronauts (“the first woman and first person of color”) onto the lunar surface for the first time since the end of the Apollo Era, over fifty years ago. They will be joined by multiple space agencies, as per the Artemis Accords, that will send European, Canadian, Japanese, and astronauts of other nationalities to the lunar surface. These will be followed in short order by taikonauts (China), cosmonauts (Russia), and vyomanauts (India), who will conduct similarly lucrative research and exploration.

Having facilities in orbit of the Moon, like the Artemis Base Camp, the International Lunar Research Station, and others, will enable all manner of scientific research that is not possible on Earth or in Earth orbit. This includes radio astronomy, which would be free of terrestrial interference on the far side of the Moon and sensitive enough to detect light from previously unexplored cosmological periods. This is the purpose of a pathfinder project known as the Lunar Surface Electromagnetics Experiment-Night (LuSEE-Night) that will leave for the Moon next year and spend the next 18 months listening to the cosmos!

October 1, 2023October 3, 2023 by Laurence Tognetti

Supernovae Struck the Earth 3 Million and 7 Million Years Ago

X-ray image of the Tycho supernova, also known as SN 1572, located between 8,000 and 9,800 light-years from Earth. Its core collapse could result in a neutron star or a black hole, depending on final mass. (Credit: X-ray: NASA/CXC/RIKEN & GSFC/T. Sato et al; Optical: DSS)

A recent study examines how the Earth was hit by blasts from supernovae (plural form of supernova (SN)) that occurred 3 million years ago (Mya) and 7 Mya with the goal of ascertaining the distances of where these blasts originated. Using the live (not decaying) radioactive isotope 60-Fe, which is produced from supernovae, a team of researchers at the University of Illinois was able to determine the approximate astronomical distances to the blasts, which they refer to as Pliocene Supernova (SN Plio, 3 Mya) and the Miocene Supernova (SN Mio, 7 Mya).

October 1, 2023October 1, 2023 by Brian Koberlein

The World's Largest Radio Telescope has Scanned Barnard's Star for Extraterrestrial Signals

Artist depiction of the surface of a super-Earth orbiting a red dwarf. Credit: ESO/M. Kornmesser

Barnard’s Star is a small red dwarf just six light-years from Earth. Despite its proximity, it was only noticed in 1916 when E. E. Barnard found it had a particularly high proper motion. It had appeared in photographic plates taken by Harvard Observatory in the late 1800s, but as a small dim star, no one took notice of it. Since its discovery, Barnard’s Star has been one of the most studied red dwarfs.

September 30, 2023September 30, 2023 by Andy Tomaswick

Let the Robot Take the Wheel. Autonomous Navigation in Space

Tracking spacecraft as they traverse deep space isn’t easy. So far, it’s been done manually, with operators of NASA’s Deep Space Network, one of the most capable communication arrays for contacting probes on interplanetary journeys, checking data from each spacecraft to determine where it is in the solar system. As more and more spacecraft start to make those harrowing trips between planets, that system will not be scalable. So engineers and orbital mechanics experts are rushing to solve this problem – and now a team from Politecnico di Milano has developed an effective technique that would be familiar to anyone who has seen an autonomous car.

September 30, 2023September 30, 2023 by Brian Koberlein

The Milky Way's Mass is Much Lower Than We Thought

The rotation curve of our galaxy compared to the Keplerian rotation curve. Credit: Jiao, Hammer et al. / Observatoire de Paris – PSL / CNRS / ESA / Gaia / ESO / S. Brunier

How massive is the Milky Way? It’s an easy question to ask, but a difficult one to answer. Imagine a single cell in your body trying to determine your total mass, and you get an idea of how difficult it can be. Despite the challenges, a new study has calculated an accurate mass of our galaxy, and it’s smaller than we thought.

September 29, 2023September 29, 2023 by Laurence Tognetti

Since Aliens Obey the Laws of Physics, Can We Guess What They Look Like?

Since time immemorial, humans have gazed up at the stars and wondered if we’re alone in the universe. We have asked if there are other intelligent beings out there in the vastness of the cosmos, also known as extraterrestrial intelligence (ET). Yet, despite our best efforts, we have yet to confirm the existence of ET outside of the Earth. While the search continues, it’s fair to speculate if they might look “human” or humanoid in appearance, or if they could look like something else entirely. Here, we present a general examination and discussion with astrobiologists pertaining to what ET might look like and what environmental parameters (e.g., gravity, atmospheric makeup, stellar activity) might cause them to evolve differently than humans.