Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A snow line in an infant solar system: Astronomers take first images

19.07.2013
Like the elevation in the Rocky Mountains where the snow caps begin, a snow line in a solar system is the point where falling temperatures freeze and clump together water or other chemical compounds that would otherwise be vapor. Astronomers believe snow lines in space serve a vital role in forming planets because frozen moisture can help dust grains stick together.

Astronomers have, for the first time, directly imaged a snow line at another star. Using the new Atacama Larger Millimeter/submillimeter Array (ALMA) telescope in Chile, they obtained radio-wavelength images of the carbon monoxide snow line around TW Hydrae, a young star 175 light-years away from Earth. TW Hydrae, in the constellation Hydra, is believed to be our closest infant solar system.

"We've had evidence of snow lines in our own solar system, but now we're able to see one with our own eyes. That is exciting," said Edwin Bergin, professor of astronomy in the University of Michigan College of Literature, Science and the Arts. Bergin is co-author on a paper on the results published in Science Express on July 18.

Different chemical compounds freeze at different distances from a central star. In our own solar system, water freezes at about five times the distance from the Earth to the sun, between the orbits of Mars and Jupiter. Various chemical compounds' snow lines may be linked to the formation of specific kinds of planets. The carbon monoxide line in our system corresponds to the orbit of Neptune, and it could also mark the starting point where smaller icy bodies like comets and dwarf planets like Pluto would form, according to the National Radio Astronomy Observatory.

Until now, snow lines have only been detected by their spectral signature. They have never been imaged directly, so their precise location and extent could not be determined.

"ALMA has given us the first real picture of a snow line around a young star, which is extremely exciting because of what it tells us about the very early period in the history of our own solar system," said co-author Chunhua "Charlie" Qi, a researcher with the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "We can now see previously hidden details about the frozen outer reaches of another solar system, one that has much in common with our own when it was less than 10 million years old."

Snow lines have been difficult to image because they only form in the relatively narrow central plane of a planet-forming disk. Above and below this region, radiation from the central star keeps the gases warm.

An outer cocoon of hot gas prevents astronomers from peering inside the disk where the gas is frozen. Instead, they hunted for a different molecule called diazenylium. Carbon monoxide gas destroys diazenylium, so it is only detectable in regions where the gas is frozen. It shines brightly in the millimeter portion of the electromagnetic spectrum, which can be detected by radio telescopes like ALMA.

By tracing the distribution of diazenylium, astronomers identified a boundary approximately 30 astronomical units from TW Hydrae. An astronomical unit is the average distance between the Earth and the sun.

"Using this technique, we were able to create, in effect, a photonegative of the carbon monoxide snow in the disk surrounding TW Hydrae," said Karin Öberg, also with Harvard but who was with the University of Virginia at the time of the observation. "With this, we could see the snow line precisely where theory predicts it should be—the inner rim of the diazenylium ring."

Öberg also points out that this snow line is particularly interesting since carbon monoxide ice is needed to form methanol, which is a building block of more complex organic molecules essential for life. Comets and asteroids could then ferry these molecules to newly forming Earth-like planets, seeding them with the ingredients for life.

ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA construction and operations are led on behalf of Europe by the European Southern Observatory, on behalf of North America by the National Radio Astronomy Observatory and on behalf of East Asia by the National Astronomical Observatory of Japan. The Joint ALMA Observatory provides the unified leadership and management of the construction, commissioning and operation of ALMA.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities Inc.

Nicole Casal Moore | EurekAlert!
Further information:
http://www.umich.edu

More articles from Physics and Astronomy:

nachricht First Juno science results supported by University of Leicester's Jupiter 'forecast'
26.05.2017 | University of Leicester

nachricht Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology

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: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>