Earth Science News
STELLAR CHEMISTRY
Astronomers discover blazing Betelgeuse has companion star
Astronomers discover blazing Betelgeuse has companion star
by AFP Staff Writers
Paris (AFP) July 21, 2025

Since at least the time of the ancient Egyptians, people across the world have gazed up in awe at Betelgeuse, one of the brightest stars blazing in the night sky.

Now astronomers have discovered that this red supergiant, known to many as the hunter's shoulder in the Orion constellation, is being orbited by a much smaller companion star, a study said on Monday.

It is not the first time Betelgeuse has surprised stargazers.

Seemingly out of nowhere, the giant star dramatically dimmed for five months between 2019 and 2020, leading some scientists to suggest it could soon die in an epic supernova explosion.

Further observations revealed that this event -- known as the "Great Dimming" -- was actually caused by material ejected from the surface that cooled part of the star, creating a dust cloud that blocked its light.

But scientists could still not explain why Betelgeuse's brightness changes regularly, both on a 400-day cycle and another that lasts nearly six years.

In a paper titled "A Buddy for Betelgeuse" published in December, some researchers theorised that the longer variation could be caused by a hidden small star orbiting the behemoth.

Astronomers using the Gemini North telescope in Hawaii have now discovered this elusive companion, according to a new study in The Astrophysical Journal Letters.

- Little buddy -

This companion has a mass around 1.5 times greater than our Sun, the research estimated.

That means it is dwarfed by Betelgeuse, which is 1,000 times bigger than the Sun.

The companion star is around four times the distance from Betelgeuse as the Earth is from the Sun, which is quite close for a stellar companion.

The discovery is the first time such a close companion star has been detected orbiting a supergiant, according to a statement from the US research centre NOIRLab, which operates the Gemini Observatory.

Betelgeuse is more than 10,000 times brighter than the Sun, its blinding light making spotting anything nearby difficult.

Steve Howell, a NASA scientist who led the research team, said previous "papers that predicted Betelgeuse's companion believed that no one would likely ever be able to image it".

However the Gemini North telescope was able to spot the much smaller, dimmer star using a technique called speckle imaging.

This involves assembling many images taken with short exposure times to overcome the distortions that Earth's atmosphere causes ground-bound telescopes.

According to Greek myth, the giant hunter Orion claimed he would kill all the world's beasts, so Earth goddess Gaia sent a scorpion to kill him. God king Zeus then turned both Orion and the scorpion -- Scorpius -- into constellations.

Earlier, ancient Egyptians included Betelgeuse in the constellation Osiris, their god of the dead.

Even earlier, research has suggested that Indigenous Australians included Betelgeuse in their own constellations -- and had noticed the star's varying brightness.

pcl-dl/giv

ORION

Related Links
Stellar Chemistry, The Universe And All Within It

Subscribe Free To Our Daily Newsletters
Tweet

RELATED CONTENT
The following news reports may link to other Space Media Network websites.
STELLAR CHEMISTRY
Crystalline grains found in space ice challenge assumptions about its structure
London, UK (SPX) Jul 08, 2025
Ice commonly found in space is not entirely amorphous, as long believed, but instead contains nanoscale crystals, according to a new study by scientists at University College London (UCL) and the University of Cambridge. The findings revise long-held views about low-density amorphous ice, which forms under extremely cold conditions in comets, icy moons, and interstellar dust clouds. The research team used computer simulations and experimental methods to investigate the atomic-level structure of th ... read more

STELLAR CHEMISTRY
New Zealand farmers battle pine forests to 'save our sheep'

French anger over bee-killing pesticide piles pressure on Macron

Cognac maker Remy Cointreau lifts guidance after China deal

'Garden of Eden': Albania eyes up growing exotic fruit for Europe

STELLAR CHEMISTRY
Greece mulls water-saving moves as heatwave intensifies

Cook Islands wages war on 'plague' of hungry starfish

New global study shows freshwater is disappearing at alarming rates

Pacific climate pioneer still fears for island nation's future

STELLAR CHEMISTRY
World court climate ruling: non-binding but game changing

World's top court paves way for climate reparations

Hundreds protest over water shortages in drought-hit Iraq

Trump administration expected to say greenhouse gases aren't harmful

STELLAR CHEMISTRY
Bio inspired design approach aims to enhance durability and scalability of perovskite solar cells

Perovskite solar cell performance shows seasonal variation in long-term field test

Bifacial CuInSe2 solar cells achieve record efficiency on transparent substrates

Wind-driven tech powers solar panel dust removal without external electricity

STELLAR CHEMISTRY
Electron beam method converts Teflon waste into reusable gases

Italy fines oil giant Eni over bioplastic market abuse

Acid vapor boosts durability of carbon dioxide-to-fuel devices

Turning CO2 into Sustainable Fuels Could Revolutionize Clean Energy

STELLAR CHEMISTRY
Israel announces 'tactical pause' in Gaza to allow aid to starving

Extreme weather misinformation 'putting lives at risk,' study warns

Contaminated Fukushima soil delivered to Japan PM office

Western aid cuts cede ground to China in Southeast Asia: study

STELLAR CHEMISTRY
US Treasury chief says China talks could cover Iran, Russia oil buys

Top court takes aim at fossil fuels in sweeping ruling

U.N. report cites 'flagrant' violations by Russia and North Korea

Baghdad and Arbil agree to resume Kurdish oil exports: government

STELLAR CHEMISTRY
Xi says China, EU must deepen trust but bloc chief urges 'real solutions'

Trump announces 'massive' Japan trade deal

Tokyo's Nikkei leads Asian rally after Japan-US trade deal

US-China set to meet with extension of tariff pause on the cards

Subscribe Free To Our Daily Newsletters




The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.