Astronomers Directly Image Betelgeuse’s Stellar Companion
Using the Speckle ‘Alopeke imaging on the north telescope of Gemini, half of the NSF Gemini International Gemini Observatory, astronomers have captured direct images of Betelgeuse – the lightest supergianteer on Earth – and its companion star.
Betelgeuse (right) and her companion stellar (left). Image credit: International Gemini Observatory / Noillab / NSF / Aura / M. Zamani, NSF’s Narsab.
Betelgeuse is a red supergiant aged 8 million years old located at around 724 light years on the shoulder of the Orion Constellation.
With a radius of about 1,400 times larger than that of the sun, it is one of the largest known stars.
Also known as Alpha Orionis or Alpha Ori, Betelgeuse is also one of the brightest stars, emitting more light than 100,000 suns.
The star approaches the end of its lifespan, and when it explodes, the event will be shiny enough to see during the day for weeks.
Betelgeuse has a main period of variability of approximately 400 days and a more extensive secondary period of about six years.
In 2019 and 2020, there was a sharp decrease in Betelgeuse’s brightness – an event called “Great Grease”.
The event led some to believe that an explosion of supernova was approaching quickly, but astronomers were able to determine that the gradation was caused by a large cloud of dust ejected with betelgeuse.
The great mystery of Gradin was resolved, but the event aroused a renewed interest in studying the red supergiant, which caused new analyzes of archive data on the star.
An analysis led scientists to propose that the cause of the variability at six years of Betelgeuse is the presence of a complementary star.
But when the NASA / ESA Hubble Spatial Telescope and the NASA Chandra X -ray observatory have sought this companion, no detection was carried out.
To search for Betelgeuse’s stellar, named Alpha Ori B or Betelbuddy, Dr. Steve Howell from the NASA Ames Research Center and his colleagues used the Speckle ‘Alopeke imaging on the Gemini North telescope.
“Speckle imaging is an astronomical imaging technique that uses very short exhibition times to freeze the distortions of the images caused by the earth’s atmosphere,” they said.
“This technique allows high resolution, which, combined with the 8.1 m mirror collection power of Gemini North, has enabled direct detection of the low companion companion.”
The analysis of the complementary star light allowed astronomers to determine the characteristics of the complementary star.
They found that it was six amplitudes weaker than betelger in the optical wavelength range, it has an estimated mass of about 1.5 solar masses, and it seems that it is a type A or B-sequence star-a hot star, young-white blue-white that has not yet initiated hydrogen burn in its nucleus.
The companion is at a distance relatively close to the betelge surface – about four times the distance between the earth and the sun.
This discovery is the first time that a nearby stellar companion has been detected in orbit in orbit a supergal star.
Even more impressive – the companion orbit well in the external extended atmosphere of betelgeuse, proving the incredible Alopeke resolution capacities.
“The capabilities of spots provided by the International Gemini Observatory continue to be a spectacular tool, open to all astronomers for a wide range of astronomy applications,” said Dr. Martin Still, director of the NSF program for the International Gemini Observatory.
“The delivery of the solution to the betelge problem that is located for hundreds of years will be an evocative success.”
The results appear today in the Astrophysical newspaper letters.
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Steve Howell and al. 2025. Discovery of probable direct imaging of the stellar companion of Betelgeuse. Apjlin press; DOI: 10.3847 / 2041-8213 / ADEAAF
