Featured Research

from universities, journals, and other organizations

Peanut-shaped Stellar Explosion Spotted By Hubble

Date:
April 25, 2009
Source:
Royal Astronomical Society (RAS)
Summary:
Using the NASA/ESA Hubble Space Telescope (HST), astronomers have taken the first optical images of a dramatic stellar outburst and discovered a peanut-shaped bubble expanding rapidly into space.

HST/ACS image of the RS Ophiuchi remnant.
Credit: NASA/HST and Valerio Ribeiro

Using the NASA / ESA Hubble Space Telescope (HST), an international team of astronomers have taken the first optical images of a dramatic stellar outburst and discovered a peanut-shaped bubble expanding rapidly into space.

Team member Valerio Ribeiro, a graduate student from Liverpool John Moores University presented their results on Wednesday 22nd April at the European Week of Astronomy and Space Science conference at the University of Hertfordshire.

The scientists looked at a star in the constellation of Ophiuchus (known as RS Oph) which has undergone a series of outbursts over the last century. On 12th February 2006, Japanese amateur astronomers reported it had brightened once again and had even become visible to the unaided eye. This was the first eruption of RS Oph since 1985 and gave scientists the unprecedented opportunity to study it using new more powerful telescopes on the ground and in space, including the HST.

RS Oph consists of a white dwarf, a dead star about the size of Earth in orbit around a much larger star, a so called red giant. Due to its proximity the white dwarf pulls hydrogen rich gas from the outer layers of the red giant and roughly every 20 years the build up of gas on the white dwarf’s surface causes a cataclysmic thermonuclear explosion. The rise to maximum brightness takes place in less than a day and at its height the energy output of RS Oph increases to over 100,000 times that of the Sun. The eruption ejects a quantity of material equivalent to the mass of the Earth at speeds of several thousand kilometres per second.

The red giant is also continuously losing enormous amounts of gas in a wind that envelops the whole system. As a result, the explosion on the white dwarf occurs effectively inside its companion's atmosphere and the ejected gas then slams into it at very high speed.

Using the HST, observations of RS Oph were made 155 and 449 days after the outburst. Combined with spectroscopy from ground-based telescopes, the first images revealed a double-lobed “peanut” structure with material expanding outwards at between 1000 and 3000 km per second.

The team attribute the shaping of the nebula to the pre-existing red giant wind. In a binary system like this, material gathers towards the plane of the stars’ orbits while at the poles it is less dense. When the outburst takes place, the ejected material hits the high density gas in the orbital plane and slows down rapidly, while at the poles it moves more quickly. The result is the peanut shape seen in the HST images and confirmed earlier observations made using radio telescopes on the ground.

Valerio Ribeiro now hopes to watch RS Oph over the years to come. He comments, “There are some astronomers who believe systems like this will ultimately explode as supernovae. Our continuing work will help us find out if that will happen.”


Story Source:

The above story is based on materials provided by Royal Astronomical Society (RAS). The original article was written by Robert Massey. Note: Materials may be edited for content and length.


Cite This Page:

Royal Astronomical Society (RAS). "Peanut-shaped Stellar Explosion Spotted By Hubble." ScienceDaily. ScienceDaily, 25 April 2009. <www.sciencedaily.com/releases/2009/04/090422085837.htm>.
Royal Astronomical Society (RAS). (2009, April 25). Peanut-shaped Stellar Explosion Spotted By Hubble. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2009/04/090422085837.htm
Royal Astronomical Society (RAS). "Peanut-shaped Stellar Explosion Spotted By Hubble." ScienceDaily. www.sciencedaily.com/releases/2009/04/090422085837.htm (accessed August 28, 2014).

Share This




More Space & Time News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com
Space to Ground: Hello Georges

Space to Ground: Hello Georges

NASA (Aug. 18, 2014) Europe's ATV-5 delivers new science and the crew tests smart SPHERES. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins