Space

February 8, 2013

NASA TELESCOPES DISCOVER STROBE-LIKE FLASHES IN A SUSPECTED BINARY PROTOSTAR

[Left] This is a false-color, infrared-light Spitzer image of LRLL 54361 inside the star-forming region IC 348 located 950 light-years away. The Spitzer Space Telescope discovered an unusual variable object that has the typical signature of a protostar. The object emits a burst of light every 25.34 days.

[Center] This Hubble Space Telescope monochromatic-color image resolves the detailed structure around the protostar, consisting of two cavities that are traced by light scattered off their edges above and below a dusty disk. The cavities were likely blown out of the surrounding natal envelope of dust and gas by an outflow launched near the central object.

[Right] This is an artist’s impression of the hypothesized central object that may be two young binary stars. Astronomers propose that the flashes are due to material in a circumstellar disk suddenly being dumped onto the growing stars and unleashing a blast of radiation each time the stars get close to each other in their orbit.

WASHINGTON — Two of NASA’s great observatories, the Spitzer and
Hubble space telescopes, have teamed up to uncover a mysterious
infant star that behaves like a strobe light.

Every 25.34 days, the object, designated LRLL 54361, unleashes a burst
of light. Although a similar phenomenon has been observed in two
other young stellar objects, this is the most powerful such beacon
seen to date.

The heart of the fireworks is hidden behind a dense disk and envelope
of dust. Astronomers propose the light flashes are caused by periodic
interactions between two newly formed stars that are binary, or
gravitationally bound to each other. LRLL 54361 offers insights into
the early stages of star formation when lots of gas and dust is being
rapidly accreted, or pulled together, to form a new binary star.

Astronomers theorize the flashes are caused by material suddenly being
dumped onto the growing stars, known as protostars. A blast of
radiation is unleashed each time the stars get close to each other in
their orbits. This phenomenon, called pulsed accretion, has been seen
in later stages of star birth, but never in such a young system or
with such intensity and regularity.

“This protostar has such large brightness variations with a precise
period that it is very difficult to explain,” said James Muzerolle of
the Space Telescope Science Institute in Baltimore, Md. His paper
recently was published in the science journal Nature.

Discovered by NASA’s Spitzer Space Telescope, LRLL 54361 is a variable
object inside the star-forming region IC 348, located 950 light-years
from Earth. Data from Spitzer revealed the presence of protostars.
Based on statistical analysis, the two stars are estimated to be no
more than a few hundred thousand years old.

The Spitzer infrared data, collected repeatedly during a period of
seven years, showed unusual outbursts in the brightness of the
suspected binary protostar. Surprisingly, the outbursts recurred
every 25.34 days, which is a very rare phenomenon.

Astronomers used NASA’s Hubble Space Telescope to confirm the Spitzer
observations and reveal the detailed stellar structure around LRLL
54361. Hubble observed two cavities above and below a dusty disk. The
cavities are visible by tracing light scattered off their edges. They
likely were blown out of the surrounding natal envelope of dust and
gas by an outflow launched near the central stars. The disk and the
envelope prevent the suspected binary star pair from being observed
directly. By capturing multiple images over the course of one pulse
event, the Hubble observations uncovered a spectacular movement of
light away from the center of the system, an optical illusion known
as a light echo.

Muzerolle and his team hypothesized the pair of stars in the center of
the dust cloud move around each other in a very eccentric orbit. As
the stars approach each other, dust and gas are dragged from the
inner edge of a surrounding disk. The material ultimately crashes
onto one or both stars, which triggers a flash of light that
illuminates the circumstellar dust. The system is rare because close
binaries account for only a few percent of our galaxy’s stellar
population. This is likely a brief, transitory phase in the birth of
a star system.

Muzerolle’s team next plans to continue monitoring LRLL 54361 using
other facilities including the European Space Agency’s Herschel Space
Telescope. The team hopes to eventually obtain more direct
measurements of the binary star and its orbit.

For related images and video, visit:

http://hubblesite.org/news/2013/04

For more information on Hubble visit:

www.nasa.gov/hubble

http://hubblesite.org/

For more information on Spitzer, visit:

www.nasa.gov/spitzer




All of this week's top headlines to your email every Friday.


 
 

 

Headlines May 20, 2015

News: Top secret X-37B space plane blasts off on fourth mission - One of the most mysterious craft ever to go into orbit blasted off on a top secret mission this morning.   Business: R&D budget request rises for U.S. Special Operations - The leadership of U.S. Special Operations Command said the force and its acquisitions –...
 
 

News Briefs May 20, 2015

North Korea ‘many years’ from developing submarine missile A top U.S. military officer says North Korea is many years away from being able to launch ballistic missiles from a submarine. But vice chairman of the U.S. Joint Chiefs of Staff, Adm. James Winnefeld, said May 19 such missiles could eventually present a hard-to-detect danger to...
 
 
Boeing photograph

Boeing-upgraded French AWACS take flight

Boeing photograph A French AWACS aircraft patrols the skies as part of a routine mission. The French AWACS fleet is in the midst of the Mid-Life Upgrade that modernizes the capabilities on board. Initial operating capability of...
 

 
CAE photograph

MH-60R FMS team supports Royal Australian Navy

CAE photograph A military representative ìfliesî the MH-60R Seahawk tactical operational flight trainer over Sydney, Australia, during a recent simulation event. In February, the Royal Australian Navy procured a trainer, simi...
 
 
boeing-E4B

Boeing returns Air Force E-4B aircraft to service ahead of schedule

Boeing recently completed maintenance on a U.S. Air Force E-4B advanced airborne command post earlier than planned, enabling the Air Force to quickly return the vital aircraft to operational service. It was the first E-4B servi...
 
 
Photograph by Linda KC Reynolds

Olympic Athletes make it special for everyone

A Special Olympics athlete is presented a medal by TSgt. Roger Rouse, assistant NCOIC at F-35 Avionics. More than 300 athletes and 80 military personnel participated in the event at Palmdale High School. Sincerely appreciated, ...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>