Hubble Blue Bubble Nebula WR 31a: Photogenic Wolf-Rayet Star

Summary: The Hubble blue bubble nebula WR 31a is a Wolf-Rayet cloud whose same-named star “lives fast and dies hard” as a supernova in a few hundred thousand years.

Hubble blue bubbles appears to encircle Wolf–Rayet star known as WR 31a; image credit -- ESA/Hubble & NASA, Acknowledgement --Judy Schmidt: NASA Mission Hubble Team, "Hubble’s Blue Bubble," Feb. 26, 2016, Generally not subjec to copyright in the United States, via NASA

Hydrogen castoffs and stellar winds are responsible for the photogenic Hubble blue bubble nebula WR 31a, according to a statement Feb. 26, 2016, by the National Aeronautics and Space Administration (NASA).

The bubble belongs to a dust-, helium- and hydrogen-rich nebula that surrounds a stellar type discovered in 1867 by French astronomers Georges Rayet and Charles Wolf. The cloud’s formation comes from stellar winds of 2.2 million to 5.4 million miles (3.6 million to 9 million kilometers) per hour removing outer stellar layers.

Scientists at the European Space Agency describe the Hubble blue bubble nebula WR 31a as within the southern constellation Carina (Keel) 30,000 light-years away from Earth. They estimate that the nebula “is expanding at a rate of around 220,000 kilometers (136,700 miles) per hour!”

WR 31a fits into categories of “live fast and die hard” stars whose original masses are at least 20 times that of the solar system’s Sun. Scientists give the Hubble blue bubble nebula WR 31a an age of around 20,000 years and its star an existence of a few hundred thousand years. The solar system’s Sun in contrast has an estimated age of about 4.5 billion years and an expected lifespan of at least 5 billion years more. A Wolf-Rayet star is far less long-lived because hydrogen supplies are consumed rapidly and gases begin getting stripped away by stellar winds in early evolutionary stages.

Scientists judge that the mass of a Wolf-Rayet star is half that of the original in less than 100,000 years.

Scientists know that the Hubble blue bubble nebula WR 31a exhibits an immediately recognizable spectrum because of rapid, vast emissions of highly ionized helium and nitrogen. The loss of hydrogen from the outer layers of WR 31a leads the Wolf-Rayet star into the evolutionary stage of fusing heavy elements for fuel. The switch to elements far heavier than hydrogen means that WR 31a, as a Wolf-Rayet star, will explode as a supernova whose material will get recycled.

Scientists note that, as the “spectacular supernova” WR 31a, “the stellar material expelled from its explosion will later nourish a new generation of stars and planets.” They offer the designations ESO 128-18 and Hen 3-519 as two other names by which WR 31a will be remembered.

Scientists provide as famous examples of Wolf-Rayet stars Gamma Velorum in the southern constellation Vela (Ship Sails) and Theta Muscae in the southern constellation Musca (Fly). The two previously mentioned Wolf-Rayet stars qualify respectively as the brightest and closest such celestial object in the first case and the second-brightest in the second.

RMC 136a1, in the Tarantula Nebula of the Large Magellanic Cloud, remains the biggest Wolf-Rayet star and the hottest, most massive, most luminous of all known stars.

The Hubble’s Advanced Camera for Surveys’ Wide Field Camera serves as source of the image made through a wide V-band (F606W) and a near-infrared (F814W) filter.

NASA takes its Hubble blue bubble nebula WR 31a from amateur astronomer Judy Schmidt’s submission to Hubble’s Hidden Treasures competition.

WR 31a is located about 30,000 light years away, in Carina the Keel constellation: NASA Goddard Images @NASAGoddardPix, via Twitter Feb. 26, 2016

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

t: NASA Mission Hubble Team, "Hubble’s Blue Bubble," Feb. 26, 2016, Generally not subjec to copyright in the United States, via NASA @ https://www.nasa.gov/image-feature/goddard/2016/hubbles-blue-bubble

WR 31a is located about 30,000 light years away, in Carina the Keel constellation: NASA Goddard Images @NASAGoddardPix, via Twitter Feb. 26, 2016, @ https://twitter.com/NASAGoddardPix/status/703247376136458241

For further information:

Dvorsky, George. 26 February 2016. “This Massive Star Sure Is Beautiful, Too Bad It’s Doomed.” Gizmodo.
Available @ http://gizmodo.com/this-massive-star-sure-is-beautiful-too-bad-its-doomed-1761498692

European Space Agency. 26 February 2016. “Hubble’s Blue Bubble.” National Aeronautics and Space Administration > Missions > Hubble Space Telescope.
Available @ http://www.nasa.gov/image-feature/goddard/2016/hubbles-blue-bubble

Fox News. 29 February 2016. “Hubble Captures Star’s Stunning Blue Bubble.” Fox News > Science > Astronomy.
Available @ http://www.foxnews.com/science/2016/02/29/hubble-captures-stars-stunning-blue-bubble.html

Goodwin, Martha. 29 February 2016. “'Blue Bubble' Nebula Is the Star of Hubble’s New Photo Shoot.” Lighthouse News Daily.
Available @ http://www.lighthousenewsdaily.com/tag/wr31a/

Luciani, Massimo. 24 February 2016. “The Star WR 31a and the Bubble Nebula Surrounding It Photographed by the Hubble Space Telescope.” Tachyon Beam > 2016 > February 24.
Available @ http://english.tachyonbeam.com/2016/02/24/the-star-wr-31a-and-the-bubble-nebula-surrounding-it-photographed-by-the-hubble-space-telescope/

NASA Goddard Images @NASAGoddardPix. 26 February 2016. "Stunning view 30,000 light years away, as Hubble enters a Blue Period. We're liking it!" Twitter.
Available @ https://twitter.com/NASAGoddardPix/status/703247376136458241

NewsBeat Social. 29 February 2016. "Look: Hubble Captures Brilliant Blue 'Bubble.'" YouTube.
Available @ https://www.youtube.com/watch?v=2_84yi84638

Prostak, Sergio. 22 February 2016. “Hubble Space Telescope Snaps Incredible Image of Wolf-Rayet Star.” Sci-News > Astronomy.
Available @ http://www.sci-news.com/astronomy/hubble-image-wolf-rayet-star-03648.html