Universe Today

December 11, 2023December 11, 2023 by Mark Thompson

15 Years of Data Reveal the Events Leading Up to Betelgeuse’s “Great Dimming”

Betelgeuse's dimming over the years. Image: ESO's Very Large Telescope

Anyone who regularly watches the skies may well be familiar with the constellation Orion the hunter. It is one of the few constellations that actually looks like the thing it is supposed to look like rather than some abstract resemblance. One prominent star is Betelgeuse and back in 2020 it dimmed to a level lower than ever before in recorded history. A team of astronomers have been studying the event with some fascinating results.

December 11, 2023December 11, 2023 by Andy Tomaswick

A Giant Stream of Stars is Flowing in Deep Space

The space between galaxies has long been considered a dead area. Single rogue stars may pop stars may pop up here or there, but the majority of this cosmic backward was considered empty by astronomers. But now, a paper from astronomers at various European and California institutions has found a trail of stars flowing between galaxies in a cluster.

December 10, 2023December 10, 2023 by Andy Tomaswick

Scientists Found Evidence Of A Nearby Kilonova 3.5 Million Years Ago

Most of the times astronomers reported dramatic, cataclysmic events like neutron star mergers or the creation of a black hole; they are taking place light years away, typically in in another galaxy. While we can observe their destructive power through the light they emit, they have minimal impact on Earth. However, a relatively recent discovery of certain types of isotopes at the bottom of the ocean hints at one of these events happening fairly close to home. And it probably didn’t happen all that long ago.

December 9, 2023December 9, 2023 by Mark Thompson

What Could a Next Generation Event Horizon Telescope Do?

Image of the M87 black hole by EHT and a CGI image photon ring. Image credit: EHT, Center for Astrophysics | Harvard & Smithsonian

Telescopes have come a long way in a little over four hundred years! It was 1608 that Dutch spectacle maker Hans Lippershey who was said to be working with a case of myopia and, in working with lenses discovered the magnifying powers if arranged in certain configurations. Now, centuries on and we have many different telescope designs and even telescopes in orbit but none are more incredible than the Event Horizon Telescope (EHT). Images las year revealed the supermassive black hole at the centre of our Galaxy and around M87 but now a team of astronomers have explored the potential of an even more powerful system the Next Generation EHT (ngEHT).

December 9, 2023December 9, 2023 by Mark Thompson

Iran Sent a Capsule Capable of Holding Animals into Orbit.

Image of the launch of the Salaman rocket by the Iranian Space Agency

Despite popular opinion, the first animals in space were not dogs or chimps, they were fruit flies launched by the United States in February 1947. The Soviet Union launched Laika, the first dog into space in November 1957 and now, it seems Iran is getting in on the act. A 500kg capsule known as the “indigenous bio-capsule” with life support capability was recently launched atop the Iranian “Salman” rocket. It has been reported by some agencies that there were animals on board but no official statement has been released.

December 8, 2023December 9, 2023 by Matt Williams

If Our Part of the Universe is Less Dense, Would That Explain the Hubble Tension?

Ten areas in the sky were selected as “deep fields” that the Dark Energy Camera imaged several times during the survey, providing a glimpse of distant galaxies and helping determine their 3D distribution in the cosmos. Credit: NSF/DES/NOIRLab/DOE/FNAL/AURA/University of Alaska Anchorage/

In the 1920s, Edwin Hubble and Georges Lemaitre made a startling discovery that forever changed our perception of the Universe. Upon observing galaxies beyond the Milky Way and measuring their spectra, they determined that the Universe was expanding. By the 1990s, with the help of the Hubble Space Telescope, scientists took the deepest images of the Universe to date and made another startling discovery: the rate of expansion is speeding up! This parameter, denoted by Lambda, is integral to the accepted model of cosmology, known as the Lambda Cold Dark Matter (LCDM) model.

Since then, attempts to measure distances have produced a discrepancy known as the “Hubble Tension.” While it was hoped that the James Webb Space Telescope (JWST) would resolve this “crisis in cosmology,” its observations have only deepened the mystery. This has led to several proposed resolutions, including the idea that there was an “Early Dark Energy” shortly after the Big Bang. In a recent paper, an international team of astrophysicists proposed a new solution based on an alternate theory of gravity that states that our galaxy is in the center of an “under-density.”

December 8, 2023December 9, 2023 by Brian Koberlein

Did the Last Great Galactic Merger Create the Milky Way's Bar?

Milky Way. Image credit: NASA/JPL-Caltech/R. Hurt (SSC/Caltech)

The Milky Way is a spiral galaxy. More specifically, it is a barred spiral galaxy, meaning that within its central region, there is a bar shape off of which the spirals emanate. About two-thirds of spiral galaxies are barred spirals, and astronomers have thought this difference is just a variance in how density waves cluster stars in a galaxy. But a new study suggests that the bar of the Milky Way may have been caused by an ancient collision with another galaxy.

December 8, 2023December 8, 2023 by Carolyn Collins Petersen

A Star Near the Center of the Milky Way is a Visitor from Beyond

The alien star S0-6 is spiraling toward Sagittarius A*, the Milky Way's central supermassive black hole. S0-6 likely came from another galaxy. Courtesy: Miyagi University of Education/NAOJ. Image credit: NASA/JPL

There’s an alien red giant star orbiting in the center of our galaxy. It’s called S0-6 and has chemical fingerprints from its birthplace far outside the Milky Way. This ancient star is spiraling slowly in toward the supermassive black hole Sagittarius A* (Sgr A*) at the heart of the Milky Way. Eventually, it could get drawn into the black hole and destroyed after traveling for tens of thousands of years to get there.

December 8, 2023December 8, 2023 by Laurence Tognetti

The International Space Station Celebrates 25 Years in Space

NASA recently celebrated the 25^th anniversary of the International Space Station (ISS) with a space-to-Earth call between the 7-person Expedition 70 crew and outgoing NASA Associate Administrator, Bob Cabana, and ISS Program Manager, Joel Montalbano. On December 6, 1998, the U.S.-built Unity module and the Russian-built Zarya module were mated in the Space Shuttle Endeavour cargo bay, as Endeavour was responsible for launching Unity into orbit that same day, with Zarya having waited in orbit after being launched on November 20 from Kazakhstan.

December 7, 2023December 9, 2023 by Nancy Atkinson

Fly Slowly Through Enceladus' Plumes to Detect Life

The plumes of Enceladus have phosphate-rich ice grains entrained. Credit: NASA — A NASA illustrations of Cassini flying through the plumes of Enceladus. Credit: NASA.

Enceladus is blasting water into space from the jets at its southern pole. This makes it the ideal place to send a dedicated mission, flying the spacecraft through the plumes with life-detection instruments s. A new study suggests that a spacecraft must proceed carefully through the plumes, keeping its speed below 4.2 km/second (2,236 miles per hour). Using a specialized, custom-built aerosol impact spectrometer at these speeds will allow fragile amino acids to be captured by the spacecraft’s sample collector. Any faster, they’ll shatter, providing inclusive results.