. 24/7 Space News .
STELLAR CHEMISTRY
Study of supergiant star Betelgeuse unveils the cause of its pulsations
by Staff Writers
Tokyo, Japan (SPX) Feb 09, 2021

Stellar pulsation causes the star's brightness to vary, but the large dip in brightness in early 2020 is unprecedented. A comparison of direct images of the surface of Betelgeuse between January 2019 and December 2019 show that large portions of the star faded in December 2019, which could indicate a dust cloud appearing in front of it. The images were taken by the European Southern Observatory's (ESO's) Very Large Telescope. For brightness data, see the caption of Fig 2.

Betelgeuse is normally one of the brightest, most recognizable stars of the winter sky, marking the left shoulder of the constellation Orion. But lately, it has been behaving strangely: an unprecedentedly large drop in its brightness has been observed in early 2020 (Figure 1), which has prompted speculation that Betelgeuse may be about to explode.

To find out more, an international team of scientists, including Ken'ichi Nomoto at the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), conducted a rigorous examination of Betelgeuse.

They concluded that the star is in the early core helium-burning phase (which is more than 100,000 years before an explosion happens) and has smaller mass and radius -- and is closer to Earth -- than previously thought. They also showed that smaller brightness variations of Betelgeuse have been driven by stellar pulsations, and suggested that the recent large dimming event involved a dust cloud.

The research team is led by Dr. Meridith Joyce from the Australian National University (ANU), who was an invited speaker at Kavli IPMU in January 2020, and includes Dr. Shing-Chi Leung, a former Kavli IPMU project researcher and a current postdoctoral scholar at the California Institute of Technology, and Dr. Chiaki Kobayashi, an associate professor at the University of Hertfordshire, who has been an affiliate member of Kavli IPMU.

The team analyzed the brightness variation of Betelgeuse (Figure 2) by using evolutionary, hydrodynamic and seismic modelling. They achieved a clearer idea than before that Betelgeuse is currently burning helium in its core.

They also showed that stellar pulsations driven by the so-called kappa-mechanism is causing the star to continuously brighten or fade with two periods of 185 (+-13.5) days and approximately 400 days. But the large dip in brightness in early 2020 is unprecedented, and is likely due to a dust cloud in front of Betelgeuse, as seen in the image (Figure 1).

Their analysis reported a present-day mass of 16.5 to 19 solar mass -- which is slightly lower than the most-recent estimates. The study also revealed how big Betelgeuse is, as well as its distance from Earth. The star's actual size has been a bit of a mystery: earlier studies, for instance, suggested it could be bigger than the orbit of Jupiter.

However, the team's results showed Betelgeuse only extends out to two-thirds of that, with a radius 750 times the radius of the sun.

Once the physical size of the star is known, it will be possible to determine its distance from Earth. Thus far, the team's results show it is a mere 530 light years from us, or 25 percent closer than previously thought.

Their results imply that Betelgeuse is not at all close to exploding, and that it is too far from Earth for the eventual explosion to have significant impact here, even though it is still a really big deal when a supernova goes off. And as Betelgeuse is the closest candidate for such an explosion, it gives us a rare opportunity to study what happens to stars like this before they explode.

Standing on the Shoulders of Giants: New Mass and Distance Estimates for Betelgeuse through Combined Evolutionary, Asteroseismic, and Hydrodynamic Simulations with MESA

Research paper


Related Links
Kavli Institute For The Physics And Mathematics Of The Universe
Stellar Chemistry, The Universe And All Within It


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


STELLAR CHEMISTRY
An art lover dreams of space
Boston MA (SPX) Feb 04, 2021
It started with a movie. Supernovas filled the screen and exploded with galactic color. The voice of Neil DeGrasse Tyson narrated the beginning of the universe. At only 14 years old, Alana Sanchez was hooked. Prior to high school, Sanchez was primarily interested in visual arts and movies. She taught herself animation and aspired to work in the creative realm. However, her dreams quickly transformed after watching the popular science documentary, "Cosmos: A Spacetime Odyssey." Today, Sanchez is an ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
NASA completes spacewalk to finish power system upgrades

Calnetix Technologies Supplies Key Components for NASA's Next-Generation CO2 Removal System

For billionaire Jared Isaacman, the space tourism era begins

NASA will pay $500,000 for good ideas on food production in space

STELLAR CHEMISTRY
SpaceX Crew Dragon team to break US record for on Sunday

Private Chinese company launches smart suborbital rocket

NASA proceeds with plans for second hot fire test

Businessman plans first all-civilian SpaceX flight to benefit St. Jude's hospital

STELLAR CHEMISTRY
An innovative and non-destructive strategy to analyse material from Mars

Tianwen 1 makes orbital correction as Mars arrival draws near

Martian landslides caused by underground salts and melting ice?

China's space probe sends back its first image of Mars

STELLAR CHEMISTRY
Three generations dedicated to space program

China's space station core module, cargo craft pass factory review

China's space tracking ship completes satellite launch monitoring

Key modules for China's next space station ready for launch

STELLAR CHEMISTRY
Astra to Become the First Publicly Traded Space Launch Company on NASDAQ via Merger with Holicity

SpaceX launches fourth Starlink mission of 2021

SpaceX plans two communications satellite cluster launches in a day

Astroscale appoints new Director, GEO Spacecraft Systems

STELLAR CHEMISTRY
MDA extends satellite operations capability through contract award by the Canadian Space Agency

Discoveries at the edge of the periodic table: first ever measurements of einsteinium

Scientists figure out why food sometimes sticks to nonstick pans

Sony forecasts record profit after PlayStation 5 launch

STELLAR CHEMISTRY
SPIRou Stares at a Young Rebel: the AU Mic Planetary System

Harvard astronomer argues that alien vessel paid us a visit

Could game theory help discover intelligent alien life

TESS discovers four exoplanets orbiting a nearby sun-like star

STELLAR CHEMISTRY
Peering at the Surface of a Nearby Moon

A Hot Spot on Jupiter

The 15th Anniversary of New Horizons Leaving Earth

Juno mission expands into the future









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.