Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. 24/7 Space News .




IRON AND ICE
NASA's 3-D Study of Comets Reveals Chemical Factory at Work
by Staff Writers
Greenbelt MD (SPX) Aug 12, 2014


This rotating 3-D map shows how HCN molecules (made of hydrogen, carbon and nitrogen) are released from the nucleus of comet Lemmon and then spread evenly throughout the atmosphere, or coma. Similar maps revealed that HNC and formaldehyde are produced in the coma, rather than the comet's nucleus. Image courtesy Brian Kent/NRAO/AUI/NSF.

A NASA-led team of scientists has created detailed 3-D maps of the atmospheres surrounding comets, identifying several gases and mapping their spread at the highest resolution ever achieved.

"We achieved truly first-of-a-kind mapping of important molecules that help us understand the nature of comets," said Martin Cordiner, a researcher working in the Goddard Center for Astrobiology at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Cordiner led the international team of researchers.

Almost unheard of for comet studies, the 3-D perspective provides deeper insight into which materials are shed from the nucleus of the comet and which are produced within the atmosphere, or coma. This helped the team nail down the sources of two key organic, or carbon-containing, molecules.

The observations were conducted in 2013 on comets Lemmon and ISON using the Atacama Large Millimeter/submillimeter Array, or ALMA, a network of high-precision antennas in Chile. These comets are the first to be studied with ALMA.

The ALMA observations combine a high-resolution 2-D image of a comet's gases with a detailed spectrum at each point. From these spectra, researchers can identify the molecules present at every point and determine their velocities (speed plus direction) along the line-of-sight; this information provides the third dimension - the depth of the coma.

"So, not only does ALMA let us identify individual molecular species in the coma, it also gives us the ability to map their locations with great sensitivity," said Anthony Remijan, a scientist with the National Radio Astronomy Observatory, one of the organizations that operates ALMA, and a co-author of the study.

The researchers reported results for three molecular species, focusing primarily on two whose sources have been difficult to discern (except in comet Halley). The 3-D maps indicated whether each molecule was flowing outward evenly in all directions or coming off in jets or in clumps.

In each comet, the team found that two species - formaldehyde and HNC (made of one hydrogen, one nitrogen and one carbon) - were produced in the coma. For formaldehyde, this confirmed what researchers already suspected, but the new maps contained enough detail to resolve clumps of the material moving into different regions of the coma day-by-day and even hour-by-hour.

For HNC, the maps settled a long-standing question about the material's source. Initially, HNC was thought to be pristine interstellar material coming from the nucleus of a comet, whereas later work suggested other possible sources. The new study provided the first proof that HNC is produced during the breakdown of large molecules or organic dust in the coma.

"Understanding organic dust is important, because such materials are more resistant to destruction during atmospheric entry, and some could have been delivered intact to early Earth, thereby fueling the emergence of life," said Michael Mumma, Director of the Goddard Center for Astrobiology, and a co-author on the study.

"These observations open a new window on this poorly known component of cometary organics."

The observations, published by the Astrophysical Journal Letters, also were significant because modest comets like Lemmon and ISON contain relatively low concentrations of crucial molecules, making them difficult to probe in depth with Earth-based telescopes. The few comprehensive studies of this kind so far have been conducted on bright, blockbuster comets, such as Hale-Bopp. The present results extend them to comets of only moderate brightness.

.


Related Links
Goddard Space Flight Center
Asteroid and Comet Mission News, Science and Technology






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





IRON AND ICE
Rosetta and Philae: Profile of comet-chasing team
Paris (AFP) Aug 06, 2014
Following is a profile of the Rosetta spacecraft, its payload Philae and the instruments they carry: ROSETTA The backbone of the Rosetta mission is a large unmanned spacecraft designed to orbit 67P/Comet Churyumov-Gerasimenko as it races through the Solar System and scans its icy head with an array of hi-tech eyes. This orbiter, Rosetta, is a 2.9-tonne box measuring 2.8 x 2.1 x 2.0 m ... read more


IRON AND ICE
China to test recoverable moon orbiter

China to send orbiter to moon and back

August supermoon will be brightest this year

Manned Moon Mission to Cost Russia $2.8 Bln

IRON AND ICE
Opportunity Heads to 'Marathon Valley'

NASA Mars Curiosity Rover: Two Years and Counting on Red Planet

Robotic Rock Climbers Could Uncover Clues to Mars' Past

Russia To Construct Landing Pad For ExoMars Mission

IRON AND ICE
Introducing this year's underground astronauts

American Spaceports

NASA Selects Proposals for Advanced Energy Storage Systems

NEEMO 18 Aquanauts Complete Underwater Mission

IRON AND ICE
More Tasks for China's Moon Mission

China's Circumlunar Spacecraft Unmasked

China to launch HD observation satellite this year

Lunar rock collisions behind Yutu damage

IRON AND ICE
ESA's cargo vessel ready for space delivery

Robonaut Upgrades, Spacewalk Preps and Cargo Ops for ISS Crew

US EVAa Delayed; Crew Preps For Russian EVA, Robonaut Upgrades

Europe's Fifth and Final Resupply Ship Launches to Station

IRON AND ICE
ATK Passes Critical Design Review for NASA's Space Launch System Booster

Russia to Decide on Future of Sea Launch Project by End of 2014

SpaceX launches AsiaSat8 into orbit via Falcon 9 rocket

United Launch Alliance Launches Two Rockets in Just Four Days

IRON AND ICE
Rotation of Planets Influences Habitability

Planet-like object may have spent its youth as hot as a star

Young binary star system may form planets with weird and wild orbits

Hubble Finds Three Surprisingly Dry Exoplanets

IRON AND ICE
BAE Systems touts its Artisan radar system

Association of satellite operators joins program for space safety

USN Moderates CubeSat RF Communications Standards Meeting

IT outsourcing boom boosts struggling Bulgaria




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.