Sidewinding young starjets spied by Gemin

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Image: The curvy young stellar jet, MHO 2147, snakes lazily through a star field in this image taken from Chile by the Gemini International Observatory, a program of NSF’s NOIRLab. The stellar jet is the outflow of a young star that is embedded in a black infrared cloud. Astronomers suspect that its lateral appearance is caused by the gravitational pull of companion stars. These crystal-clear observations were made using the Gemini South telescope’s adaptive optics system, which helps astronomers counteract the hazy effects of atmospheric turbulence.
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Credit: Gemini International Observatory/NOIRLab/NSF/AURA Acknowledgements: Image processing: TA Rector (University of Alaska Anchorage/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab) and D. de Martin (NSF’s NOIRLab) IP: L. Ferrero (Universidad Nacional de Córdoba)

Meandering stellar jets meander lazily through a star field in new images captured from Chile by the Gemini International Observatory, a program of NSF’s NOIRLab. The gently curved stellar jets are the outflow of young stars, and astronomers suspect that their sideways appearances are caused by the gravitational pull of companion stars. These crystal-clear observations were made using the Gemini South telescope’s adaptive optics system, which helps astronomers counteract the hazy effects of atmospheric turbulence.

Young stellar jets are a common by-product of star formation and are thought to be caused by the interaction between the magnetic fields of rotating young stars and the discs of gas around them. These interactions eject twin torrents of ionized gas in opposite directions, like those shown in two images captured by astronomers using the Gemini South telescope on Cerro Pachón on the edge of the Chilean Andes. Gemini South is one half of the Gemini International Observatory, a program of NSF’s NOIRLab, which includes twin 8.1-meter optical/infrared telescopes at two of the best observing sites on the planet. Its counterpart, Gemini North, is located near the summit of Maunakea in Hawai’i.

The jet in the first image, named MHO 2147, is about 10,000 light-years from Earth and lies within the galactic plane of the Milky Way, near the boundary between the constellations of Sagittarius and Ophiuchus. MHO 2147 snakes against a starry background in the image – a serpentine appearance appropriate for an object close to Ophiuchus. Like many of the 88 modern astronomical constellations, Ophiuchus has mythological roots – in ancient Greece it represented a variety of gods and heroes wrestling with a serpent. MHO 1502, the jet shown in the second image, is located in the constellation of Vela, about 2000 light years away.

Most star jets are straight but some can be roving or knotted. The shape of the jagged jets is thought to be related to some characteristic of the object or objects that created them. In the case of the two bipolar jets MHO 2147 and MHO 1502, the stars that created them are occulted.

In the case of MHO 2147, this central young star, which has the catchy identifier IRAS 17527-2439, is embedded in an infrared dark cloud – a region of cool, dense gas that is opaque to the infrared wavelengths depicted in this picture. [1]. The curvy shape of MHO 2147 is due to the direction of the jet changing over time, tracing a gentle curve on either side of the central star. These almost uninterrupted curves suggest that MHO 2147 was sculpted by continuous emission from its central source. Astronomers have discovered that the change in direction (precession) of the jet may be due to the gravitational influence of nearby stars acting on the central star. Their observations suggest that IRAS 17527-2439 may belong to a system of triple stars separated by more than 300 billion kilometers (nearly 200 billion miles).

MHO 1502, on the other hand, is embedded in a totally different environment – a star forming area known as the HII region. The bipolar jet is made up of a string of nodes, suggesting that its source, thought to be two stars, emits material intermittently.

These detailed images were captured by the Gemini South Adaptive Optics Imager (GSAOI), an instrument of the 8.1-meter-diameter Gemini South Telescope. Gemini South is perched atop Cerro Pachón, where dry air and negligible cloud cover make for one of the best viewing spots on the planet. Even atop Cerro Pachón, however, atmospheric turbulence causes the stars to blur and twinkle.

GSAOI works with GeMs, the Gemini Multiconjugate Adaptive Optics System, to cancel out this blurring effect using a technique called adaptive optics. By monitoring the twinkling of natural and man-made guide stars up to 800 times per second, GeMs can determine how atmospheric turbulence is distorting Gemini South observations [2]. A computer uses this information to fine-tune the shape of the deformable mirrors, canceling out the distortions caused by turbulence. In this case, the sharp adaptive optics images allowed more detail to be recognized in each node of the young stellar jets than in previous studies.

Remarks

[1] Astronomical objects can appear very different at different wavelengths. For example, the dust surrounding newborn stars blocks visible light but is transparent to infrared wavelengths. Something similar also happens here on Earth – doctors can see right through you with an x-ray machine even though human bodies are not transparent to visible wavelengths. Astronomers therefore study the Universe across the electromagnetic spectrum to learn as much as possible about the Universe.

[2] Adaptive optics systems on telescopes often use “natural guide stars”, which are bright stars located close to the target of an astronomical observation. Their brightness makes it easy to measure how much atmospheric turbulence distorts their appearance. Gemini South also uses artificial guide stars produced by shooting powerful lasers into the upper atmosphere.

More information

The observations of this image have been published in the article High resolution images of two agitated stellar jets, MHO 1502 and MHO 2147, obtained with GSAOI+GeMS, to be published in the journal Astronomy and astrophysics.

The team was made up of LV Ferrero (Universidad Nacional de Córdoba and Consejo Nacional de Investigaciones Científicas y Técnicas [CONICET]), G. Günthardt (Universidad Nacional de Córdoba), L. García (Universidad Nacional de Córdoba), M. Gómez (Universidad Nacional de Córdoba and CONICET), VM Kalari (Universidad de Chile and Gemini Observatory/NSF’s NOIRLab), and HP Saldaño (Universidad Nacional de Córdoba).

NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, ANID– Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC) and Vera C Rubin Observatory (in cooperation with the SLAC National Accelerator Laboratory). It is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, Maunakea in Hawai’i, and Cerro Tololo and Cerro Pachón in Chile. We recognize and recognize the very important cultural role and respect these sites have for the Tohono O’odham Nation, the Native Hawaiian community and the local communities of Chile, respectively.

Connections

contacts

Leticia Ferrero
National University of Cordoba
Tel: ​+54 9 351 4331063/4/5 int: 105
Email: [email protected]

Amanda Kocz
NOIRLab NSF Communications
Tel: +1 520 318 8591
Email: [email protected]


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