betelgeuse Archives

August 28, 2024August 28, 2024 by Mark Thompson

Is Betelgeuse Actually a Binary Star?

This image, made with the Atacama Large Millimeter/submillimeter Array (ALMA), shows the red supergiant Betelgeuse — one of the largest stars known. In the millimeter continuum the star is around 1400 times larger than our Sun. The overlaid annotation shows how large the star is compared to the Solar System. Betelgeuse would engulf all four terrestrial planets — Mercury, Venus, Earth and Mars — and even the gas giant Jupiter. Only Saturn would be beyond its surface. Link Betelgeuse captured by ALMA Scientific paper

Betel-gurz or Beetle-juice has been a favourite among amateur astronomers for many years. However you pronounce it, its unexpected dimming draw even more attention to this red supergiant variable star in Orion. It has a few cycles of variability, one of them occurs over a 2,170 day period, 5 times longer than its normal pulsation period. A paper has just been published that suggests a companion star of 1.17 solar masses could be the cause. It would need an orbit about 2.43 times the radius of Betelgeuse and it might just lead to the modulation of dust in the region that causes the variations we see.

May 30, 2024May 30, 2024 by Andy Tomaswick

A New Telescope Can Observe Even in Broad Daylight

Astronomy is a profession that, so far, has only been done at night, at least on Earth. Light from the Sun overwhelms any light from other stars, making it impractical for both professional and amateur astronomers to look at the stars during daytime. There are several disadvantages to this, not the least of which is that many potentially exciting parts of the sky aren’t visible at all for large chunks of the year as they pass too close to the Sun. To solve this, a team from Macquarie University, led by graduate student Sarah Caddy, developed a multi-camera system for a local telescope that allows them to observe during daytime.

March 7, 2024March 7, 2024 by Mark Thompson

Betelgeuse’s Surface is Boiling Furiously

Simulation of Betelgeuse's boiling surface

Of all the stars in the sky, betelgeuse must be among the most enigmatic. One of its many mysteries surrounds the speed of its rotation which is surprisingly fast for a supergiant star. If it were placed where the Sun was, then its photosphere (visible layer) would be out around the orbit of Jupiter and it would be moving at 5 km/s. A new study now hints that instead of high rotation, it may be that the surface is boiling so furiously that it has been mistakingly identified as fast rotation.

January 10, 2024January 10, 2024 by Evan Gough

A Giant Star is Fading Away. But First, it Had an Enormous Eruption

Astronomers from Georgia State University’s CHARA Array have captured the first close-up images of a massive star known as RW Cephei that recently experienced a strange fading event. The images are providing new clues about what’s happening around the massive star approximately 16,000 light years from Earth. Image Credit: GSU/CHARA, Anugu et al. 2023

About 16,000 light-years away, a massive star experienced an unusual dimming event. This can happen in binary stars when one star passes in front of the other. It can also be due to intrinsic reasons like innate variability. But this star dimmed by as much as one-third, a huge amount.

What happened?

December 3, 2023December 3, 2023 by Mark Thompson

Does Betelgeuse Even Rotate? Maybe Not

Image showing Betelgeuse (top left) and the dense nebulae of the Orion molecular cloud complex (Rogelio Bernal Andreo) — Orion and the molecular cloud covering the region. Betelgeuse is the red star in the upper left. (Credit : Rogelio Bernal Andreo)

Betelgeuse is the well known red giant star in the corner of Orion the hunter. The name translated in some languages means ‘armpit of the giant’ which I think of all the star names, is simply the best! Betelgeuse has been fascinating observers of late not only because it unexpectedly faded a few years ago but more recently a study shows it’s super fast rotational speed which is, when compared to other supergiants, is like nothing seen before.

September 16, 2022September 16, 2022 by Laurence Tognetti

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?

July 18, 2022July 20, 2022 by Scott Alan Johnston

Betelgeuse and Antares Have Been Observed for Over 2,000 Years. Astronomers can use This to Figure out how old They are

Stars don’t usually evolve fast enough for humans to notice them change within one lifetime. Even a hundred lifetimes won’t do – astronomical processes are just too slow. But not always. There are some phases of stellar evolution that happen quickly, and when they do, they can be tracked. A new paper posted to ArXiv last week uses astronomical observations found in ancient Roman texts, medieval astronomical logs, and manuscripts from China’s Han Dynasty to trace the recent evolution of several bright stars, including red supergiant Antares, and Betelgeuse: one of the most dynamic stars in our sky. With observations from across the historical record, the paper suggests that Betelgeuse may have just recently passed through the ‘Hertzsprung gap,’ the transitional phase between a main sequence star and its current classification as a red supergiant.

June 16, 2022June 16, 2022 by Evan Gough

Astronomers Caught Betelgeuse Just Before it Started Dimming and Might Have Seen a Pressure Wave Rippling Through its Atmosphere

Betelgeuse was the first star directly imaged -- besides our own Sun, of course. Image obtained by the Hubble Space Telescope. Credit: Andrea Dupree (Harvard-Smithsonian CfA), Ronald Gilliland (STScI), NASA and ESA

A couple of years ago, Betelgeuse generated much interest when it started dimming. That caught the attention of astronomers worldwide, who tried to understand what was happening. Was it about to go supernova?

Evidence showed that dust was the most likely culprit for the red supergiant’s dimming, though there are still questions. A new study shows that the star was behaving strangely just before the dimming.

March 9, 2021March 9, 2021 by Andy Tomaswick

VY Canis Majoris is “Like Betelgeuse on Steroids”

The disappearance of a star can take many forms. It could go supernova. It could turn into a black hole. Or it could just fade away quietly. Sometimes, the last of these is actually the most interesting to observe. That is the case for one of the largest stars ever found – VY Canis Majoris, a red supergiant approximately 3840 light years away in the Canis Major constellation.

January 25, 2021January 25, 2021 by Paul M. Sutter

Astronomers Hoped to see Evidence of Dark Matter Particles Inside Betelgeuse. No Luck

An artist's impression of Betelgeuse. Its surface is covered by large star spots, which reduce its brightness. During their pulsations, such stars regularly release gas into their surroundings, which condenses into dust. Image Credit: MPIA graphics department

Axions are a hypothetical particle that might explain the existence of dark matter. But it might occasionally interact with normal matter, especially in the cores of stars. A team of physicists have searched for evidence of axions in Betelgeuse and come up with nothing. It doesn’t mean that the axion doesn’t exist, but it does mean that it will be harder to find.