Featured Research

from universities, journals, and other organizations

Young star suggests our sun was a feisty toddler

Date:
June 5, 2013
Source:
Harvard-Smithsonian Center for Astrophysics
Summary:
If you had a time machine that could take you anywhere in the past, what time would you choose? Most people would probably pick the era of the dinosaurs in hopes of spotting a T. rex. But many astronomers would choose the period, four and a half billion years ago, that our solar system formed. New work suggests that our sun was both active and "feisty" in its infancy, growing in fits and starts while burping out bursts of X-rays.

TW Hydrae system. This artist's conception illustrates what we would see if we could zoom in on the TW Hydrae system. We are viewing the star nearly pole-on, where streamers of gas from the surrounding protoplanetary disk funnel onto the star. Research shows that this growth process, also known as accretion, is clumpy and episodic. By studying TW Hydrae we can learn what our Sun was like when it was only 10 million years old.
Credit: David A. Aguilar (CfA)

If you had a time machine that could take you anywhere in the past, what time would you choose? Most people would probably pick the era of the dinosaurs in hopes of spotting a T. rex. But many astronomers would choose the period, four and a half billion years ago, that our solar system formed.

Related Articles


In lieu of a working time machine, we learn about the birth of our Sun and its planets by studying young stars in our galaxy. New work suggests that our Sun was both active and "feisty" in its infancy, growing in fits and starts while burping out bursts of X-rays.

"By studying TW Hydrae, we can watch what happened to our Sun when it was a toddler," said Nancy Brickhouse of the Harvard-Smithsonian Center for Astrophysics (CfA). She presented the findings today in a press conference at a meeting of the American Astronomical Society.

Brickhouse and her colleagues reached this conclusion by studying the young star TW Hydrae, located about 190 light-years from Earth in the southern constellation Hydra the Water Snake. TW Hydrae is an orange, type K star weighing about 80 percent as much as our Sun. It is about 10 million years old, and is still accreting gas from a surrounding disk of material. That same disk might contain newborn planets.

In order to grow, the star "eats" gas from the disk. However, the disk doesn't extend all the way to the star's surface, so the star can't dine from it directly. Instead, infalling gas gets funneled along magnetic field lines to the star's poles.

Fortunately, we are looking almost directly down on one of the star's poles. As a result, we can study the accretion process in detail.

"We're looking right where the action is," said team member Andrea Dupree of the CfA.

Infalling material smashes into the star, creating a shock wave and heating the accreting gas to temperatures greater than 5 million degrees Fahrenheit. The gas glows with high-energy X-rays. As it continues moving inward, the gas cools and its glow shifts to optical wavelengths of light. To study the process, Brickhouse and her team combined observations from NASA's Chandra X-ray Observatory with those from ground-based optical telescopes.

"By gathering data in multiple wavelengths we followed the gas all the way down. We traced the whole accretion process for the first time," explained Brickhouse.

They found that accretion was clumpy and episodic in building a star. At one point the amount of material landing on the star changed by a factor of five over the course of a few days.

"The accretion process changes from night to night. Things are happening all the time," stated Dupree.

Some of the infalling material is pushed away in a stellar wind much like the solar wind that fills our solar system. Some gets channeled into giant loops and stellar prominences.

Astronomers have known that young stars are much more magnetically active than our middle-aged Sun, but now they can actually probe the interplay between the star's magnetic fields and the protoplanetary disk.

"The very process of accretion is driving magnetic activity on TW Hydrae," added Brickhouse.


Story Source:

The above story is based on materials provided by Harvard-Smithsonian Center for Astrophysics. Note: Materials may be edited for content and length.


Cite This Page:

Harvard-Smithsonian Center for Astrophysics. "Young star suggests our sun was a feisty toddler." ScienceDaily. ScienceDaily, 5 June 2013. <www.sciencedaily.com/releases/2013/06/130605133600.htm>.
Harvard-Smithsonian Center for Astrophysics. (2013, June 5). Young star suggests our sun was a feisty toddler. ScienceDaily. Retrieved January 26, 2015 from www.sciencedaily.com/releases/2013/06/130605133600.htm
Harvard-Smithsonian Center for Astrophysics. "Young star suggests our sun was a feisty toddler." ScienceDaily. www.sciencedaily.com/releases/2013/06/130605133600.htm (accessed January 26, 2015).

Share This


More From ScienceDaily



More Space & Time News

Monday, January 26, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Water Fleas Prepare for Space Voyage

Water Fleas Prepare for Space Voyage

Reuters - Innovations Video Online (Jan. 26, 2015) Scientists are preparing a group of water fleas for a unique voyage into space. The aquatic crustaceans, known as Daphnia, can be used as a miniature model for biomedical research, and their reproductive and swimming behaviour will be tested for signs of stress while on board the International Space Station. Jim Drury went to meet the team. Video provided by Reuters
Powered by NewsLook.com
Mars Rover Opportunity Celebrates 11-Year Anniversary

Mars Rover Opportunity Celebrates 11-Year Anniversary

Rumble (Jan. 26, 2015) Eleven years ago NASA&apos;s Opportunity rover touched down on Mars for what was only supposed to be a 90-day mission. Since then it has traveled 25.9 miles (41.7 kilometers), further than any other off-Earth surface vehicle has ever driven. Credit to &apos;NASA&apos;. Video provided by Rumble
Powered by NewsLook.com
NASA's On Course To Take Pluto's Best Photo Ever

NASA's On Course To Take Pluto's Best Photo Ever

Newsy (Jan. 25, 2015) NASA&apos;s New Horizons probe is en route to snap a picture of Pluto this summer, but making sure it doesn&apos;t miss its one chance to do so starts now. Video provided by Newsy
Powered by NewsLook.com
Rosetta Captures Stunning Views, Diverse Data Of Comet 67P

Rosetta Captures Stunning Views, Diverse Data Of Comet 67P

Newsy (Jan. 23, 2015) The first images of the European Space Agency&apos;s Rosetta probe comet orbit could provide clues about its origin and how it got its unique shape. Video provided by Newsy
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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