The Pipe Nebula (left) and the Rho Ophiuchi cloud (right) in the Milky Way. Each inset map shows how much the light of background stars is dimmed as it passes through the cloud in question. Credit: Background: ESO/S. Guisard // Column-density maps: J. Kainulainen, MPIA
Understanding stars is fundamental to the science of astronomy: the astro in astronomy means star, after all. And courtesy of a new study researchers have a better understanding of how these things form providing insights not just into the stars themselves, but also into galactic and planetary evolution.
Astronomers werent totally in the dark about star formation. They knew that stars form within giant clouds of molecular gas (mostly hydrogen) and dust. When an area within the cloud becomes too full of molecules, it undergoes gravitational collapse the area attracts more stuff, which makes it denser and more massive, which attracts yet more stuff until enough stuff is there to ignite nuclear fusion, the process that fuels a star.
The problem was figuring out how to know when an area is too full of molecules. Whats the critical density at which gas clouds turn into stars?
Astronomers had long been trying to figure this out, and have devised many models of star formation. The only problem was, its pretty hard to measure how dense a gas cloud is to begin with.
Now astronomers have shown that they can determine a gas clouds density by analyzing how it distorts the light from distant stars behind it. The more a star dims, the more gas its traveling through, and therefore the denser the cloud is at that point.
Armed with a way of calculating a clouds density, the team carried out direct observations of 16 nearby star-forming gas clouds (within about 850 light-years of Earth) to determine a value for the critical density necessary to set off a new star: around 5,000 hydrogen molecules per cubic centimeter. Thats a lot lower than the theories had predicted (a whole order of magnitude lower, in some cases), which is surprising. Its unclear yet why the guesses were so far off. The findings appeared in this weeks Science.
Now that astronomers have this technique at their disposal, theyll be better able to test and refine their theories on star formation. That could mean a solution to one of the greatest challenges of astrophysics: being able to look at a gas cloud and predict how many stars will come out of it, and what kind of stars theyll be.
This gives researchers great predictive power in figuring out how galaxies (including our own) will behave in the future. Its also a boon to researchers who study planet formation, since star birth is the first step in the process of creating a solar system.
Read the rest here:
Stars Form Much More Readily Than Astronomers Thought
- I Spy With My Little Eye… - November 7th, 2009 [November 7th, 2009]
- A Crack Opens in the Ethiopian Landscape, Preparing the Way for a New Sea | 80beats - November 8th, 2009 [November 8th, 2009]
- The Politics of Addiction | The Intersection - November 8th, 2009 [November 8th, 2009]
- Finally! An iPhone App That Lets You Track Your Bathroom Habits | Discoblog - November 8th, 2009 [November 8th, 2009]
- Don’t Pack Your Bags Yet—New Planet-Finder Hobbled by Electronic Glitch | 80beats - November 8th, 2009 [November 8th, 2009]
- In Controversial Scent Lineups, a Dog’s Nose Picks Out the Perp | 80beats - November 8th, 2009 [November 8th, 2009]
- Are You a Cognitive Miser? | Cosmic Variance - November 8th, 2009 [November 8th, 2009]
- The Secret Lives and Loves of Great White Sharks | 80beats - November 8th, 2009 [November 8th, 2009]
- Britain’s New Protected Minority: Tree-Huggers | Discoblog - November 8th, 2009 [November 8th, 2009]
- Inspired by Maple Seeds, a Robotic Whirligig Takes To The Skies | Discoblog - November 8th, 2009 [November 8th, 2009]
- New Statesman on Accommodationism | The Intersection - November 8th, 2009 [November 8th, 2009]
- Laser-Powered Robot Climbs to Victory in the Space-Elevator Contest | 80beats - November 8th, 2009 [November 8th, 2009]
- Checking Back In With SEAPLEX | The Intersection - November 8th, 2009 [November 8th, 2009]
- Podcast: An Embarrassment of Genomes | The Loom - November 8th, 2009 [November 8th, 2009]
- A Baby Neutron Star, Swaddled in a Carbon Atmosphere | 80beats - November 8th, 2009 [November 8th, 2009]
- Butterfliiiies… iiinnnn… SPPPAAAAACCCCEEEEE! | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- My Slate Dialogue with Michael Specter Begins | The Intersection - November 8th, 2009 [November 8th, 2009]
- Musical, Fahrvergnügen-Inspired Staircase Makes Commuters Less Lazy | Discoblog - November 8th, 2009 [November 8th, 2009]
- Laser-Etched Fruit Is an Answer in Search of a Problem | Discoblog - November 8th, 2009 [November 8th, 2009]
- Ares and the carnivals | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- Toddler Gets a Telescoping, Prosthetic Arm Bone That Grows With Him | 80beats - November 8th, 2009 [November 8th, 2009]
- Neutered HIV Virus Delivers Treatment to Fatally Ill Boys | 80beats - November 8th, 2009 [November 8th, 2009]
- Specter’s First Reply: Denialism Kills People | The Intersection - November 8th, 2009 [November 8th, 2009]
- LRO sees a Moonslide | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- Al Gore’s New Book: A Focus on Solutions | The Intersection - November 8th, 2009 [November 8th, 2009]
- The Universe Has Us in Its Crosshairs | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- Makers of Universes | Cosmic Variance - November 8th, 2009 [November 8th, 2009]
- Can Your Pet Catch & Spread Swine Flu? Yes, If Your Pet’s a Ferret | 80beats - November 8th, 2009 [November 8th, 2009]
- Droid 2.0 Vs iPhone | The Intersection - November 8th, 2009 [November 8th, 2009]
- Tangled Bank News: An Excerpt and More | The Loom - November 8th, 2009 [November 8th, 2009]
- LHC Shut Down By Wayward Baguette, Dropped by Bird Saboteur | Discoblog - November 8th, 2009 [November 8th, 2009]
- Careidolia | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- Slate Reply to Specter Up–We Need a National Dialogue on Synthetic Biology | The Intersection - November 8th, 2009 [November 8th, 2009]
- Pray this doesn’t get passed | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- You Can’t Make This Stuff Up | Cosmic Variance - November 8th, 2009 [November 8th, 2009]
- Mother Tongue, Indeed: Newborn’s Cries Mimic Mama’s Accent | 80beats - November 8th, 2009 [November 8th, 2009]
- Ripped From the Journals: The Biggest Discoveries of the Week | 80beats - November 8th, 2009 [November 8th, 2009]
- Alternative Landscapes | The Loom - November 8th, 2009 [November 8th, 2009]
- Can an iPhone App Decipher Your Baby’s Cries? | Discoblog - November 8th, 2009 [November 8th, 2009]
- Reminder: Carl Sagan Day | Bad Astronomy - November 8th, 2009 [November 8th, 2009]
- Are There Pesticides in Your Soup? Dunk a Pollution Dipstick to Find Out. | 80beats - November 8th, 2009 [November 8th, 2009]
- Log in and Join the Conference - November 8th, 2009 [November 8th, 2009]
- Conference Ends - November 8th, 2009 [November 8th, 2009]
- Conference Archive Opens - November 8th, 2009 [November 8th, 2009]
- Galaxy Zoo - November 8th, 2009 [November 8th, 2009]
- .Astronomy 2009 Dates - November 8th, 2009 [November 8th, 2009]
- .Astronomy 2009: Programme and venue details - November 8th, 2009 [November 8th, 2009]
- .Astronomy Gets Some IYA Love - November 8th, 2009 [November 8th, 2009]
- 2009 Posters and Imagery - November 8th, 2009 [November 8th, 2009]
- 2009 Sponsors - November 8th, 2009 [November 8th, 2009]
- When in Holland… - November 8th, 2009 [November 8th, 2009]
- The WHAT Cloud? - November 8th, 2009 [November 8th, 2009]
- The Jewel Box - November 8th, 2009 [November 8th, 2009]
- Happy Halloween! - November 8th, 2009 [November 8th, 2009]
- Ares 1-X Launch - November 8th, 2009 [November 8th, 2009]
- Confessions of an Alien Hunter - November 8th, 2009 [November 8th, 2009]
- LRO Spies Apollo 17 Site - November 8th, 2009 [November 8th, 2009]
- Mercury in Color - November 8th, 2009 [November 8th, 2009]
- Hubble and M83 - November 8th, 2009 [November 8th, 2009]
- Cassini Flyby of Enceladus - November 8th, 2009 [November 8th, 2009]
- Preserving A Moth [Science Tattoo] | The Loom - December 12th, 2009 [December 12th, 2009]
- Another Russian rocket spiral lights up the sky | Bad Astronomy - December 12th, 2009 [December 12th, 2009]
- A (Very Gentle) Riddle to Complete Your Saturday - December 12th, 2009 [December 12th, 2009]
- Darwin Gets Swine Flu: The YouTube Edition | The Loom - December 12th, 2009 [December 12th, 2009]
- Happy Slothy Holidays | The Loom - December 12th, 2009 [December 12th, 2009]
- Jetting to Copenhagen | The Intersection - December 12th, 2009 [December 12th, 2009]
- Michael Gerson Attempts Thoughtfulness on “ClimateGate,” Then Gives it Up | The Intersection - December 13th, 2009 [December 13th, 2009]
- Incredible VISTA of the cosmos | Bad Astronomy - December 13th, 2009 [December 13th, 2009]
- Bundle up Sunday Night to Watch the Geminid Meteor Shower | 80beats - December 13th, 2009 [December 13th, 2009]
- “ClimateGate” a PR Disaster That Will Be “Taught in University Communications Courses” | The Intersection - December 13th, 2009 [December 13th, 2009]
- Is Google the Guardian Angel of Rainforests? | 80beats - December 13th, 2009 [December 13th, 2009]
- La ciencia es importante. Una vez mas. | Bad Astronomy - December 13th, 2009 [December 13th, 2009]
- Sensenbrenner Pulls an Inhofe, Asserts Global Warming is an “International Conspiracy” | The Intersection - December 13th, 2009 [December 13th, 2009]
- Let Kids Eat Dirt: Over-Cleanliness Linked to Heart Disease | 80beats - December 13th, 2009 [December 13th, 2009]
- What Are The Best Science Papers Of The Past Decade? | The Intersection - December 13th, 2009 [December 13th, 2009]
- Finally! Math Shows How to Cut Evenly Sized Pizza Slices | Discoblog - December 13th, 2009 [December 13th, 2009]
- Half-baked math | Bad Astronomy - December 13th, 2009 [December 13th, 2009]
- Can “Biological Passports” Save Sports From Doping? | 80beats - December 13th, 2009 [December 13th, 2009]
- Aiiiieeee! Slow down! | Bad Astronomy - December 13th, 2009 [December 13th, 2009]
- Weekly News Roundup: Bad Headlines, Martian moons, and Rotating Houses | Discoblog - December 13th, 2009 [December 13th, 2009]