Studying a Star Before it is Born

December 4, 2009
An Infrared Array Camera false-color image of the dark cloud Lynds 43E and its environment. The bright object is a young star nearby in the sky to the dark cloud, which lies to the left in this picture but which is dark even at these infrared wavelengths. Credit: NASA Spitzer Space Telescope

(PhysOrg.com) -- The first phase of a star's formation are thought to begin deep inside a natal cloud of gas and dust. In the earliest stages, material coalesces under the influence of gravity into so-called "dense cores," which, because they absorb optical light, are sometimes seen in the sky as black shapes against a background of stars or nebulosity.

Using modern technologies, however, astronomers today can measure both faint infrared emission from the dust as well as millimeter emission from molecules in the gas. The molecules are especially powerful probes, because their emission is a diagnostic of the chemical history of the cloud, its temperature structure, its evolutionary history, its internal motions, and more.

Astronomers are particularly interested in the earliest stages of these dense cores, even before a star appears. Lynds 43E is one of these dense cores, and is among the most optically opaque clouds known. Its mass, estimated from submillimeter studies, is about 0.8 solar-masses. It is relatively close by, about 420 light-years, in the constellation of Ophiuchus, and is associated with a much larger . There is also a young star very nearby it that conveniently offers a comparison for studies.

SAO astronomer Tyler Bourke, together with three of his colleagues, studied the nature of Lynds 43E and its neighbor using millimeter observations of the molecule and a set of rarer molecules, combined with dust emission as measured by the Spitzer Space Telescope's infrared cameras and other facilities.

They modeled the data to derive the physical conditions in each source, and a picture of how the local chemistry evolved. The scientists present a reasonable picture of where the various molecules are located throughout the core (each one has its own characteristic distribution) and how that distribution likely has evolved in time. In the end, they conclude that this dense core is about 2 million years old. The results are an important step in the meticulous unraveling of the very earliest stages of star formation.

Provided by Harvard-Smithsonian Center for Astrophysics (news : web)

Explore further: Spitzer Catches Young Stars in Their Baby Blanket of Dust

Related Stories

Astronomers Decipher Nature of Mysterious Object

October 4, 2005

In an exercise that demonstrates the power of a multiwavelength investigation using diverse facilities, astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have deciphered the true nature of a mysterious ...

Massive Stars Near the Galactic Center

August 28, 2009

The Central Molecular Zone (CMZ) of our galaxy is a giant complex of molecular gas and dust situated in the innermost 700 light-years of the Milky Way. Although the galaxy is over 100,000 light-years in size, nearly 10% of ...

Turbulence May Promote the Birth of Massive Stars

February 23, 2009

(PhysOrg.com) -- On long, dark winter nights, the constellation of Orion the Hunter dominates the sky. Within the Hunter's sword, the Orion Nebula swaddles a cluster of newborn stars called the Trapezium. These stars are ...

Coronet: A Star Formation Neighbor

September 13, 2007

While perhaps not quite as well known as its star formation cousin of Orion, the Corona Australis region (containing, at its heart, the Coronet Cluster) is one of the nearest and most active regions of ongoing star formation.

Recommended for you

Hubble catches a transformation in the Virgo constellation

December 9, 2016

The constellation of Virgo (The Virgin) is especially rich in galaxies, due in part to the presence of a massive and gravitationally-bound collection of over 1300 galaxies called the Virgo Cluster. One particular member of ...

Scientists sweep stodgy stature from Saturn's C ring

December 9, 2016

As a cosmic dust magnet, Saturn's C ring gives away its youth. Once thought formed in an older, primordial era, the ring may be but a mere babe – less than 100 million years old, according to Cornell-led astronomers in ...

Khatyrka meteorite found to have third quasicrystal

December 9, 2016

(Phys.org)—A small team of researchers from the U.S. and Italy has found evidence of a naturally formed quasicrystal in a sample obtained from the Khatyrka meteorite. In their paper published in the journal Scientific Reports, ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

omatumr
1 / 5 (3) Dec 04, 2009
That is certainly not how the Sun formed!

The Sun formed on the collapsed core of a pre-existing star.

That conclusion is based on hundreds of measurements of the solar wind, solar flares, the solar photosphere, solar neutrinos, meteorites, the Earth, the Moon, Mars and Jupiter.

With kind regards,
Oliver K. Manuel
Emeritus Professor
Nuclear & Space Science
Fromer NASA PI for Apollo
http://myprofile....anuelo09

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.