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Star Formation: Herbig-Haro 46/47

Jets emitted by young stars Full Story Below

Gas takes the shape of a diagonal hourglass.
Larger hourglass shape of dust and gas overlays tiny dots.
Dispersed, elongated spheres overlay a star field. Dispersed, elongated spheres overlay a star field.
A thin stream of light emerges from dark cloud. A thin stream of light emerges from dark cloud.
Many bright shapes overlay a dark cloud that hides stars. Many bright shapes overlay a dark cloud that hides stars.
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By looking at the coldest gas at the edge of a blown-out cavity, researchers can determine where the jets point.

The central stars and the hot, glowing gas of the inner cavity appear in far-infrared light.

Near-infrared light pierces though the dark cloud, but scattered light traces its faint outline.

One jet is largely obscured by the dark cloud of gas and dust, and the other results in a blue shock wave.

As two young stars spin, nearby gas flows onto the stars and is launched as opposing jets.


Star Formation: Herbig-Haro 46/47

A nearby example of star formation.

Star formation is an ongoing recycling process: Gravity shapes new stars from the gas and dust surrounding them, which is known as a molecular cloud. Once formed, young stars shape the dusty environment around them, blowing gas and dust out of some areas while compressing it in others. In visible light, forming stars are hidden inside thick cocoons of dust, but they emit light at other wavelengths that passes through the dust clouds and can be detected by telescopes, which provide researchers opportunities to study more of the ongoing mechanics at work.

Herbig-Haro objects like HH 46/47 are some of the nearest young stars, which make them ideal laboratories to study star formation. As stars form, they regulate how much material falls onto them from a surrounding cloud of gas and dust in part by sending out jets. HH 46/47 is made up of a pair of forming stars, but they are far enough away from other, nearby stars, which means they can form without the influence of winds from those surrounding stars. Observations across the electromagnetic spectrum, from radio to visible light, allow astronomers to identify and “peer through” HH 46/47’s surrounding molecular cloud. This has allowed them to identify the infrequent, opposing jets its stars send out and study how those jets send shock waves through the surrounding gas.

Quick Facts: Herbig-Haro 46/47

Also known as: HH 46/47

Distance from Earth: 1,470 light-years

Size: Approximately 2 light-years across

Type of object: Forming stars with jets

Location in the sky: Vela Constellation

Did you know: When astronomer Bart Bok made a follow-up observation of HH 46/47 in 1978, he identified the jets ejected by these forming stars for the first time.

Explore More About Star Formation

Find out more with these additional resources from NASA’s Universe of Learning

Astro vis Astroviz
Flight through the Orion Nebula in Visible and Infrared
Astropix AstroPix
Star Formation Nebulas
Universe unplugged Universe Unplugged
A Star is Born!
Universe of learning NASA’s Universe of Learning
Lagoon Nebula Astrophoto Challenge

Credits: Herbig-Haro 46/47

Radio image from the Atacama Large Millimeter/submillimeter Array (ALMA): ESO/ALMA (ESO/NAOJ/NRAO)/H. Arce

Far-infrared image from the Spitzer Space Telescope: NASA/JPL-Caltech/T. Velusamy (JPL)

Near-infrared image from the Víctor M. Blanco 4-m Telescope at the Cerro Tololo Inter-American Observatory: NOAO/AURA/NSF/John Bally (University of Colorado)

Visible light image from ESO’s New Technology Telescope at the La Silla Observatory: ESO/Bo Reipurth

Multi-wavelength image (radio, infrared, visible): ESO/ALMA (ESO/NAOJ/NRAO)/H. Arce; Bo Reipurth

Content development by Claire Blome, Dr. Kelly Lepo, Yesenia Perez

Design by Zena Levy

Web development by Isaar Sadr, Lara Wilkinson

Subject-matter expertise provided by Dr. John Bally