Tuesday, April 24, 2007

Star-Forming Region in the Carina Nebula

Credit for Hubble Image: NASA, ESA, N. Smith (University of California, Berkeley),
and The Hubble Heritage Team (STScI/AURA)

[Left] — A towering "mountain" of cold hydrogen gas laced with dust is the site of new star formation in the Carina Nebula. The great gas pillar is being eroded by the ultraviolet radiation from the hottest newborn stars in the nebula.

[Right] — A close-up look at the peak of one of these "pillars of creation" reveals unequivocal evidence that stars are being born inside the columns. A pencil-like streamer of gas shoots out in both directions from the pillar and plows into surrounding gas like a fire hose hitting a wall of sand. The jet is being launched from a newly forming star hidden inside the column. A similar jet appears near the bottom of the image. These stellar jets are a common signature of the birth of a new star.

Carina Nebula Details

Credit for Hubble Image: NASA, ESA, N. Smith (University of California, Berkeley),
and The Hubble Heritage Team (STScI/AURA)

This Hubble Space Telescope view of the central region of the Carina Nebula reveals a violent maelstrom of star birth. The fantasy-like landscape of the nebula is sculpted by the intense pressure of starlight from monster stars and their accompanying star clusters, as well as the hydrodynamics of their stellar winds of charged particles.

[Top] — An approximately one-light-year tall "pillar" of cold hydrogen towers above the wall of the molecular cloud. The 2.5-million-year-old star cluster called Trumpler 14 appears at the right side of the image. A small nugget of cold molecular hydrogen, called a Bok globule, is silhouetted against the star cluster.

[Center] — A Bok globule nicknamed the "caterpillar" appears at the right. Its glowing edge indicates that it is being photoionized by the hottest stars in the cluster. It has been hypothesized that stars may form inside such dusty cocoons. The top of the Keyhole Nebula, the most prominent feature embedded inside Carina, is on the left. Another Bok globule is in the foreground.

[Bottom] — These great clouds of cold hydrogen resemble summer afternoon thunderheads. They tower above the surface of a molecular cloud on the edge of the nebula. So-called "elephant trunk" pillars resist being heated and eaten away by blistering ultraviolet radiation from the nebula's brightest stars.

Carina Nebula

Credit for Hubble Image:NASA, ESA, N. Smith (University of California, Berkeley),
and The Hubble Heritage Team (STScI/AURA)

In celebration of the 17th anniversary of the launch and deployment of NASA's Hubble Space Telescope, a team of astronomers is releasing one of the largest panoramic images ever taken with Hubble's cameras. It is a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of star birth - and death - is taking place.

Hubble's view of the nebula shows star birth in a new level of detail. The fantasy-like landscape of the nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars that inhabit this inferno. In the process, these stars are shredding the surrounding material that is the last vestige of the giant cloud from which the stars were born.

The immense nebula contains at least a dozen brilliant stars that are roughly estimated to be at least 50 to 100 times the mass of our Sun. The most unique and opulent inhabitant is the star Eta Carinae, at far left. Eta Carinae is in the final stages of its brief and eruptive lifespan, as evidenced by two billowing lobes of gas and dust that presage its upcoming explosion as a titanic supernova.

The fireworks in the Carina region started three million years ago when the nebula's first generation of newborn stars condensed and ignited in the middle of a huge cloud of cold molecular hydrogen. Radiation from these stars carved out an expanding bubble of hot gas. The island-like clumps of dark clouds scattered across the nebula are nodules of dust and gas that are resisting being eaten away by photoionization.

The hurricane blast of stellar winds and blistering ultraviolet radiation within the cavity is now compressing the surrounding walls of cold hydrogen. This is triggering a second stage of new star formation.

Our Sun and our solar system may have been born inside such a cosmic crucible 4.6 billion years ago. In looking at the Carina Nebula we are seeing the genesis of star making as it commonly occurs along the dense spiral arms of a galaxy.

The immense nebula is an estimated 7,500 light-years away in the southern constellation Carina the Keel (of the old southern constellation Argo Navis, the ship of Jason and the Argonauts, from Greek mythology).

This image is a mosaic of the Carina Nebula assembled from 48 frames taken with Hubble Space Telescope's Advanced Camera for Surveys. The Hubble images were taken in the light of neutral hydrogen. Color information was added with data taken at the Cerro Tololo Inter-American Observatory in Chile. Red corresponds to sulfur, green to hydrogen, and blue to oxygen emission.