Hubble Sees the Force Awakening in a Newborn Star

 

Herbig-Haro Jet HH 24

Acknowledgment: NASA, ESA, the Hubble Heritage (STScI/AURA)/Hubble-Europe (ESA) Collaboration, D. Padgett (GSFC), T. Megeath (University of Toledo), and B. Reipurth (University of Hawaii).  Credit: NASA and ESA. Release Images

This is an artist's concept of the fireworks that accompany the birth of a star. The young stellar object is encircled by a pancake-shaped disk of dust and gas left over from the collapse of the nebula that formed the star. Gas falls onto the newly forming star and is heated to the point that some of it escapes along the star's spin axis. Intertwined by magnetic fields, the bipolar jets blast into space at over 100,000 miles per hour. As seen from far away, they resemble a double-bladed lightsaber from the Star Wars film series. Credit: NASA, ESA, and A. Feild (STScI)

Just about anything is possible in our remarkable universe, and it often competes with the imaginings of science fiction writers and filmmakers. Hubble's latest contribution is a striking photo of what looks like a double-bladed lightsaber straight out of the Star Wars films. In the center of the image, partially obscured by a dark, Jedi-like cloak of dust, a newborn star shoots twin jets out into space as a sort of birth announcement to the universe. Gas from a surrounding disk rains down onto the dust-obscured protostar and engorges it. The material is superheated and shoots outward from the star in opposite directions along an uncluttered escape route — the star's rotation axis. Much more energetic than a science fiction lightsaber, these narrow energetic beams are blasting across space at over 100,000 miles per hour. This celestial lightsaber does not lie in a galaxy far, far away but rather inside our home galaxy, the Milky Way.

Just in time for the release of the movie "Star Wars Episode VII: The Force Awakens," NASA's Hubble Space Telescope has photographed what looks like a cosmic, double-bladed lightsaber.

In the center of the image, partially obscured by a dark, Jedi-like cloak of dust, a newborn star shoots twin jets out into space as a sort of birth announcement to the universe.

"Science fiction has been an inspiration to generations of scientists and engineers, and the film series Star Wars is no exception," said John Grunsfeld, astronaut and associate administrator for NASA's Science Mission Directorate. “There is no stronger case for the motivational power of real science than the discoveries that come from the Hubble Space Telescope as it unravels the mysteries of the universe."

This celestial lightsaber does not lie in a galaxy far, far away, but rather inside our home galaxy, the Milky Way. It's inside a turbulent birthing ground for new stars known as the Orion B molecular cloud complex, located 1,350 light-years away.

When stars form within giant clouds of cool molecular hydrogen, some of the surrounding material collapses under gravity to form a rotating, flattened disk encircling the newborn star.

Though planets will later congeal in the disk, at this early stage the protostar is feeding on the disk with a Jabba-like appetite. Gas from the disk rains down onto the protostar and engorges it. Superheated material spills away and is shot outward from the star in opposite directions along an uncluttered escape route — the star's rotation axis.

Shock fronts develop along the jets and heat the surrounding gas to thousands of degrees Fahrenheit. The jets collide with the surrounding gas and dust and clear vast spaces, like a stream of water plowing into a hill of sand. The shock fronts form tangled, knotted clumps of nebulosity and are collectively known as Herbig-Haro (HH) objects. The prominent HH object shown in this image is HH 24.

Just to the right of the cloaked star, a couple of bright points are young stars peeking through and showing off their own faint lightsabers — including one that has bored a tunnel through the cloud towards the upper-right side of the picture.

Overall, just a handful of HH jets have been spotted in this region in visible light, and about the same number in the infrared. Hubble's observations for this image were performed in infrared light, which enabled the telescope to peer through the gas and dust cocooning the newly forming stars and capture a clear view of the HH objects.

These young stellar jets are ideal targets for NASA's upcoming James Webb Space Telescope, which will have even greater infrared wavelength vision to see deeper into the dust surrounding newly forming stars.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4514
villard@stsci.edu

Mathias Jäger
ESA/Hubble, Garching, Germany
011-49-176-6239-7500
mjaeger@partner.eso.org

Deborah Padgett
NASA Goddard Space Flight Center, Greenbelt, Maryland
deborah.l.padgett@nasa.gov

Bo Reipurth (available only after Jan. 8, 2016)
University of Hawaii, Hilo, Hawaii
reipurth@ifa.hawaii.edu

Tom Megeath
University of Toledo, Toledo, Ohio
megeath@physics.utoledo.edu

Source: HubbleSite

Searching for Orphan Stars Amid Starbirth Fireworks

The HH 24 jet complex emanates from a dense cloud core that hosts a small multiple protostellar system known as SSV63. The nebulous star to the south is the visible T Tauri star SSV59. Color image based on the following filters with composite image color assignments in parenthesis: g (blue), r (cyan), I (orange), hydrogen-alpha (red), sulfur II (blue)) images obtained with GMOS on Gemini North in 0.5 arcsecond seeing, and NIRI. Field of view is 4.2x5.1 arcminutes, orientation: north up, east left. Image produced by Travis Rector.  Credit: Gemini Observatory/AURA/B. Reipurth, C. Aspin, T. Rector.  Download JPG 945KB | TIFF 7.8MB 

A new Gemini Observatory image reveals the remarkable “fireworks” that accompany the birth of stars. The image captures in unprecedented clarity the fascinating structures of a gas jet complex emanating from a stellar nursery at supersonic speeds. The striking new image hints at the dynamic (and messy) process of star birth. Researchers believe they have also found a collection of runaway (orphan) stars that result from all this activity.

Gemini Observatory has released one of the most detailed images ever obtained of emerging gas jets streaming from a region of newborn stars. The region, known as the Herbig-Haro 24 (HH 24) Complex, contains no less than six jets streaming from a small cluster of young stars embedded in a molecular cloud in the direction of the constellation of Orion.

"This is the highest concentration of jets known anywhere," says Principal Investigator Bo Reipurth of the University of Hawaii’s Institute for Astronomy (IfA), who adds, "We also think the very dynamic environment causes some of the lowest mass stars in the area to be expelled, and our Gemini data are supporting that idea."

Reipurth along with co-researcher, Colin Aspin, also at the IfA, are using the Gemini North data from the Gemini Multi-Object Spectrograph (GMOS), as well as the Gemini Near-Infrared Imager, to study the region which was discovered in 1963 by George Herbig and Len Kuhi. Located in the Orion B cloud, at a distance of about 400 parsecs, or about 1,300 light-years from our Solar System, this region is rich in young stars and has been extensively studied in all types of light, from radio waves to X-rays.

"The Gemini data are the best ever obtained from the ground of this remarkable jet complex and are showing us striking new detail," says Aspin. Reipurth and Aspin add that they are particularly interested in the fine structure and "excitation distribution" of these jets.

"One jet is highly disturbed, suggesting that the source may be a close binary whose orbit perturbs the jet body," says Reipurth.

The researchers report that the jet complex emanates from what is called a Class~I protostar, SSV63, which high-resolution infrared imaging reveals to have at least five components. More sources are found in this region, but only at longer, submillimeter wavelengths of light, suggesting that there are even younger, and more deeply embedded sources in the region. All of these embedded sources are located within the dense molecular cloud core.

A search for dim optical and infrared young stars has revealed several faint optical stars located well outside the star-forming core. In particular, a halo of five faint Hydrogen-alpha emission stars (which emit large amounts of red light) has been found with GMOS surrounding the HH 24 Complex well outside the dense cloud core. Gemini spectroscopy of the hydrogen alpha emission stars show that they are early or mid-M dwarfs (very low-mass stars), with at least one of which being a borderline brown dwarf.

The presence of these five very low-mass stars well outside the star-forming cloud core is puzzling, because in their present location the gas is far too tenuous for the stars to have formed there. Instead they are likely orphaned protostars ejected shortly after birth from the nearby star-forming core. Such ejections occur when many stars are formed closely together within the same cloud core. The crowded stars start moving around each other in a chaotic dance, ultimately leading to the ejection of the smallest ones.

A consequence of such ejections is that pairs of the remaining stars bind together gravitationally. The dense gas that surrounds the newly formed pairs brakes their motion, so they gradually spiral together to form tight binary systems with highly eccentric orbits. Each time the two components are closest in their orbits they disturb each other, leading to accretion of gas, and an outflow event that we see as supersonic jets. The many knots in the jets thus represent a series of such perturbations.

Source: Gemini Observatory