Nav: Home

Massive stars grow same way as light stars, just bigger

July 08, 2019

Astronomers obtained the first detailed face-on view of a gaseous disk feeding the growth of a massive baby star. They found that it shares many common features with lighter baby stars. This implies that the process of star formation is the same, regardless of the final mass of the resulting star. This finding paves the way for a more complete understanding of star formation.

A protostar, a baby star still in the process of forming, is fed by a surrounding disk of gas falling towards the center. The details of the process, such as why stars form with a wide range of masses, are still unclear. Low mass stars are being formed in the vicinity of the Solar System, allowing astronomers to see the process up-close. On the other hand, massive protostars are rare, and even the nearest are located quite far away from us.

Kazuhito Motogi, an assistant professor at Yamaguchi University, Japan, and his team used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe a massive protostar called G353.273+0.641 (hereafter G353). Located 5500 light-years away in the constellation Scorpius, G353 has a mass 10 times larger than the Sun, and is still growing. It is a unique target among massive protostars because we can see its gaseous disk from straight above. ALMA has revealed detailed views of several other massive infant stars, however, most of them are in edge-on configurations, making it difficult to see the inner regions of the disks.

ALMA observations captured a rotating disk around G353 with a radius eight times larger than the orbit of Neptune. This sounds huge, but it is one of the smallest disks yet found around a massive protostar. ALMA also found that the disk is surrounded by an envelope of gas three times larger than the disk.

"We measured the gas infall rate from the outer envelope to the inner disk," says Motogi. "This helps us to estimate the age of the baby star. Surprisingly it is only 3000 years old, the youngest among known massive protostars. We are witnessing the earliest phase of the growth of a giant star."

Interestingly, the disk is not uniform; the south-eastern side of the disk is brighter than other parts. This is the first time astronomers have seen an asymmetric disk around a massive protostar. The team also found that the disk is highly unstable and going to fragment. The uneven disk might be caused by this instability. These features are often seen around smaller protostars, suggesting that the essential physical processes are the same in low-mass and high-mass star formation.

"Previous studies had implied that the formation process might be different for stars of different masses," says Motogi. "Our new observations show the similarity. This is an important step to understand how massive protostars gain mass from the surroundings."
-end-
The research team members are:

Kazuhito Motogi (Yamaguchi University), Tomoya Hirota (National Astronomical Observatory of Japan/SOKENDAI), Masahiro N. Machida (Kyushu University), Yoshinori Yonekura (Ibaraki University), Mareki Honma (National Astronomical Observatory of Japan/SOKENDAI), Shigehisa Takakuwa (Kagoshima University), and Satoki Matsushita (Academia Sinica Institute of Astronomy and Astrophysics)

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Yamaguchi University is a comprehensive national university with over 10,000 students in 9 faculties and 8 graduate schools. The university traces its origins back to Yamaguchi Kodo, a private school started in 1815. Yamaguchi University has put these values to words in our motto: "Discover it. Nourish it. Realize it. A Place of Wisdom," and contributes to local development and to the development of Japanese and international society through the three fields of education, research, and social contribution.

National Institutes of Natural Sciences

Related Star Formation Articles:

Star formation project maps nearby interstellar clouds
Astronomers have captured new, detailed maps of three nearby interstellar gas clouds containing regions of ongoing high-mass star formation.
Scientists discover pulsating remains of a star in an eclipsing double star system
Scientists from the University of Sheffield have discovered a pulsating ancient star in a double star system, which will allow them to access important information on the history of how stars like our Sun evolve and eventually die.
Distant milky way-like galaxies reveal star formation history of the universe
Thousands of galaxies are visible in this radio image of an area in the Southern Sky, made with the MeerKAT telescope.
Cascades of gas around young star indicate early stages of planet formation
What does a gestating baby planet look like? New research in Nature by a team including Carnegie's Jaehan Bae investigated the effects of three planets in the process of forming around a young star, revealing the source of their atmospheres.
Massive exoplanet orbiting tiny star challenges planet formation theory
Astronomers have discovered a giant Jupiter-like exoplanet in an unlikely location -- orbiting a small red dwarf star.
ALMA pinpoints the formation site of planet around nearest young star
Researchers using ALMA (Atacama Large Millimeter/submillimeter Array) found a small dust concentration in the disk around TW Hydrae, the nearest young star.
Star formation burst in the Milky Way 2-3 million years ago
A team led by researchers of the Institute of Cosmos Sciences of the University of Barcelona and the Besançon Astronomical Observatory have found, analysing data from the Gaia satellite, that a severe star formation burst occurred in the Milky Way about to and three thousand million years ago.
The rise and fall of Ziggy star formation and the rich dust from ancient stars
Researchers have detected a radio signal from abundant interstellar dust in MACS0416_Y1, a galaxy 13.2 billion light-years away in the constellation Eridanus.
Lifting the veil on star formation in the Orion Nebula
Writing in 'Nature', an international research team including astronomers from Cologne describe their discovery that stellar wind from a newborn star in the Orion Nebula is preventing more stars from forming nearby.
Massive star's unusual death heralds the birth of compact neutron star binary
Carnegie's Anthony Piro was part of a Caltech-led team of astronomers who observed the peculiar death of a massive star that exploded in a surprisingly faint and rapidly fading supernova, possibly creating a compact neutron star binary system.
More Star Formation News and Star Formation Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.