Category Archives: Gemini Observatory

american astronomical society, Gemini Observatory, Orion, Orion Nebula

Bullets of Star Formation

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Clumps of Supersonic Gas Point Back to Hot Young Stars

 

 

This image reveals exquisite details in the outskirts of the Orion Nebula. The large adaptive optics field-of-view (85 arcseconds across) demonstrates the system’s extreme resolution and uniform correction across the entire field. The three filters used for this composite color image include [Fe II], H2, and, K(short)-continuum (2.093 microns) for blue, orange, and white layers respectively. The natural seeing while these data were taken ranged from about 0.8 to 1.1 arcseconds, with AO corrected images ranging from 0.084 to 0.103 arcsecond. Each filter had a total integration (exposure) of 600 seconds. In this image, the blue spots are clouds of gaseous iron “bullets” being propelled at supersonic speeds from a region of massive star formation outside, and below, this image’s field-of-view. As these “bullets” pass through neutral hydrogen gas it heats up the hydrogen and produces the pillars that trace the passage of the iron clouds.
Principal Investigator(s): John Bally and Adam Ginsberg, University of Colorado and the GeMS/GSAOI commissioning team; Data processing/reduction: Rodrigo Carrasco, Gemini Observatory; Color image composite: Travis Rector, University of Alaska Anchorage. Image Courtesy: Gemini Observatory/AURA
The universe is not a static place. Things change all the time. So, the more often you look at an object or process in the cosmos, the more information you’ll get about how it changes over time. Astronomers take advantage of this to get what you might call a “time varying” view of something like the Sun or a planet or a star-forming region (for example). The process gets very interesting when they use newer technology to study something that seems familiar, like the Orion Nebula.

The Gemini Observatory observed a region of the Orion Nebula in 2007 and imaged what are called “bullets”. These almost look like tunnels through the clouds of gas and dust that make up the nebula. They are actually strong winds blowing gas off of massive stars at incredibly high speeds. As these “wind bullets” speed out, they carve out these tubular wakes as much as a fifth of a light-year long.

Those original images were some of the best taken of this region at the time, and they showed dynamic action surrounding hot young stars in the nebula.

Now, the Gemini Observatory has studied these again, this time using an a technology called adaptive optics and laser guide stars to gain a sharp clear image of these bullets in the Orion Nebula. The laser guide stars are artificial stars that are made using a special laser that shoots into the sky and provides astronomers a guide to aim at. They read those stars and use what they see to “adapt” the telescope system to account for the atmospheric aberration between the telescope and the sky. The process provides very clear, almost Hubble-like images, but from the ground.

The new images show more detail and, if you look closely between the originals and the new ones, you can make out a little bit of dynamic motion in the clouds themselves.

Check out the new image here, and then go over to the Gemini page and look at a previous image of the bullets — you can see clear improvements that are giving astronomers a great new tool to check out the Orion Nebula better than ever before.

 

 

galaxies, galaxy interactions, galaxy shapes, Gemini Observatory

Not Your Typical Science Fair Project

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Australian Students and Gemini Observatory

Image of NGC 6872 (left) and companion galaxy IC 4970 (right) locked in a tango as the two galaxies gravitationally interact. The galaxies lie about 200 million light-years away in the direction of the constellation Pavo (the Peacock). Image credit: Sydney Girls High School Astronomy Club, Travis Rector (University of Alaska, Anchorage), Ángel López-Sánchez (Australian Astronomical Observatory/Macquarie University), and the Australian Gemini Office.

Remember back when you entered the science fair at school? I remember a winning entry that I did — something about yeast that my mother helped cook up.  I didn’t get to go get my ribbon for that one because I was at home with measles. Nowadays, kids get vaccinated for measles (the smart parents all do this), and so having spotty bumps on one’s skin is no excuse for missing out on a science fair award.

A group of students from Sydney Girls High School in Australia went way beyond science fair with their idea — to use Gemini Observatory to study a pair of interacting galaxies called NGC 6872 and IC 4970. They were participating in a country-wide contest to suggest scientifically interesting and aesthetically pleasing objects for the observatory’s telescope to snare with its 8-meter mirror.

The contest sponsors liked their proposal so much that it was selected as the winner, and the image at right was the result. The main instrument used to make this image was the Gemini Multi-Object Spectrograph (GMOS), in its imaging mode on the Gemini South telescope in Chile.

The primary galaxy in the image (NGC 6872) shows what happens when galaxies interact and their original structure and form is distorted. When galaxies like these get too close to each other, the mutual gravitational pull starts to distort their structures. Their spiral arms get stretched out to enormous distances, with streamers of starburst knots following along. In NGC 6872, the arms have been stretched out to span hundreds of thousands of light-years—many times further than the spiral arms of our own Milky Way galaxy.

Over hundreds of millions of years, NGC 6872’s arms will fall back toward the central part of the galaxy, and the companion galaxy (IC 4970) will eventually be merged into NGC 6872. The coalescence of galaxies often leads to a burst of new star formation. Already, the blue light of recently created star clusters dot the outer reaches of NGC 6872’s elongated arms. Dark fingers of dust and gas along the arms soak up the visible light. That dust and gas is the raw material out of which future generations of stars could be born, and possibly even countless numbers of planets.

The search for these dynamic changes in galaxy structure was what sold the selection committee on the students’ observation proposal. They wrote, “If enough color data is obtained in the image it may reveal easily accessible information about the different populations of stars, star formation, relative rate of star formation due to the interaction, and the extent of dust and gas present in these galaxies.”

The team also presented a more emotional perspective by looking at the impact this image might have on people trying to understand our place in the universe. When viewers consider this image “in contrast to their daily life,” the team explained, “there is a significant possibility of a new awareness or perception of the age and scale of the universe, and their part in it.”

When I look at this picture, I really envy those kids.  Imagine getting to have your science project executed on one of the world’s premier telescopes!