Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Astronomers take revealing peek at star factory

13.01.2005


Observations eventually expected lead to increased understanding of interstellar dust and gas

Using NASA’s orbiting Far Ultraviolet Spectroscopic Explorer, a team of astronomers from The Johns Hopkins University and elsewhere has taken an unprecedented peek beneath the "skirts" of the tunic-clad Orion the Hunter and come away with observations that may lead to enhanced knowledge of how interstellar dust absorbs and scatters ultraviolet starlight. "Understanding interstellar dust is important. After all, this is the stuff out of which, ultimately, planets, stars and even people are made," said team member Richard Conn Henry, a professor in the Henry A. Rowland Department of Physics and Astronomy at Johns Hopkins. Henry presented findings during the American Astronomical Society’s meeting this week in San Diego.

The constellation Orion, named for its resemblance to a powerful, tunic-clad hunter wielding a club and sword, is probably the greatest star factory in our galaxy, with thousands of young, hot, blue stars emerging from its great clouds of gas and dust. Led by Jayant Murthy of the Indian Institute of Astrophysics, the team examined data FUSE recorded near the most active region of current star formation.



What they saw surprised them.

"FUSE detected a spectrum of ultraviolet light in a region where there is no star at all," said Murthy, who spent many years at Johns Hopkins before going to the Indian Institute. "The spectrum is of light reflecting from the dust in a region near a quite bright star, whose spectrum is very similar to that of the reflected light we detected. At first, we thought that particular star was the original source of the light. But a closer look revealed that, despite the similarity, there were differences -- differences striking enough to allow us to conclude that the star in question could not be the source of the light that is scattering from the dust. So where was that light coming from?"

Team members suspect that the light in question emanated from the Trapezium, a cluster of stars located in the heart of the Orion Nebula. So named because the configuration of its stars resembles a geometric quadrilateral with two parallel sides, the Trapezium not only is one of the most famous multiple star systems in the night sky, but is also -- at only about 1 million years old -- the youngest.

"The ultimate aim of this work is to understand exactly in what manner the light gets reflected: What is this interstellar dust from which the stars are born?" asks David Sahnow, a research scientist in the Department of Physics and Astronomy at Johns Hopkins and a member of the investigating team. "To what extent does the dust absorb the light, and to what extent does it scatter it? For that light which is scattered, does it go backward, forward, or sideways?"

Perhaps one of the most interesting aspects of this investigation into interstellar dust is that it happened serendipitously.

"This is a great example of how science works sometimes, how you can stumble across something valuable while looking for something else," said Murthy. "We were actually taking engineering tests at some semi-random places in the sky while FUSE was thermalizing, and we noticed this. Our discovery that FUSE’s high spectral resolution can actually be applied to diffuse radiation has additional ramifications. High spectral resolution is often a key to physical understanding, and our Orion observation shows that we will be able to use this technique to more deeply understand the general diffuse background radiation over the sky."

NASA funded this research. The team hopes the agency will underwrite further investigations.

"We have submitted a proposal to NASA to use FUSE over the next year to explore the ramifications of our surprise discovery that FUSE can detect diffuse emission," Henry said. "By choosing targets carefully, we can get more easily interpreted data, allowing stronger conclusions regarding the nature of interstellar dust. The observed cosmic background is not fully understood and possibly is of new cosmological importance. We are confident that with FUSE and carefully implemented further observations, we can answer many questions for the first time."

The team’s paper on its observations of Orion has been accepted for publication by the Astrophysical Journal.

Designed and operated by a team of engineers and scientists at Johns Hopkins, FUSE is the largest astrophysics mission NASA has ever handed off to a university to manage. The 18-foot tall, 3,000 pound satellite has operated for five years from its perch 475 miles above the Earth’s surface, gathering unique data about everything from planets and nearby stars to galaxies and quasars billions of light years away.

Lisa DeNike | EurekAlert!
Further information:
http://www.jhu.edu
http://henry.pha.jhu.edu/orion.html

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>