Category Archives: astronomy

A Seething Hotbed of Star Birth

Another Peek at the Orion Nebula

It’s getting to be the time of year when the Orion Nebula isn’t readily available in the night sky because — well, it’s just not a sky sight for the next few months.  So, those of us who love to explore the nebula have to “make do” with the latest in professional studies of this busy, busy star birth region.

The Orion Molecular Cloud as seen by UKIRT and Spitzer Space Telescope. (Click to emiggen -- and you WANT to!)
The Orion Molecular Cloud as seen by UKIRT and Spitzer Space Telescope. (Click to embiggen -- and you WANT to!)

The kind folks at the United Kingdom Infrared Telescope (UKIRT), the IRAM Millimeter-wave Telescope in Spain,  and the orbiting Spitzer Space Telescope did a set of observations and combined them to create this stunning infrared image of the Orion Molecular Cloud. There’s a lot going on here —  star birth is NOT a serene event (just as human births aren’t exactly quiet, respectful events).

Let’s deconstruct this image. (You might want to right-click on it and open it in a new browser window to see all the details.)  First, the glowing green areas are clouds of gas and dust that are the seed material for stars. They’re usually made up of hydrogen gas and dust particles.  There are newborn stars in here — they glow in a sort of golden orange color and they’re heating up the cloud with their ultraviolet radiation. This causes the cloud to glow in a variety of wavelengths — some of them invisible to us — like infrared, which is what UKIRT, IRAM, and Spitzer are sensitive to.

So, it stands to reason that if you want to study the intricacies of star birth, you want to study the infrared light streaming from stellar nurseries.  It can cut right through most of the gas and dust in the region and give us a peek behind the clouds that often hide starbirth from us.

Newborn stars give off more than light and heat. They also emit jets during part of their infancy and childhood. Those jets shove their way out through the clouds and help sculpt the nebula.  In this image, the jets show up as tiny pink–purple arcs and dots.

A close-up of jets in the Orion Molecular Cloud (UKIRT WFCAM). (Click to embiggen.)
A close-up of jets in the Orion Molecular Cloud (UKIRT WFCAM). (Click to embiggen.)

To see the real action in this region, the astronomers took a close-up view of a jet streaming from a newborn star in one of the busier areas of star formation in this nebula.  The image was created from data acquired by the Wide Field Camera (WFCAM) at the United Kingdom Infrared Telescope.

The jet is in red, and you can see other objects — wisps, knots and filaments — that are also jets from other young stars. .

What I find cool about studying regions like the OMC is that at the same time they give us a look at star formation in the current age of the universe, they also give us a look back at the birth pangs of our own Sun and solar system some 4.5 billion years ago.  Some of the baby stars you see popping out here will someday BE like the Sun — and maybe even have their own planets.

What if Your Eyes were REALLY Sensitive?

The Sky Would Look Really Different

The Big Picture -- the sky as seen in a long exposure with sensitive equipment.  By Dennis diCicco and Sean Walker, courtesy Astronomy Picture of the Day.
The Big Picture -- the sky as seen in a long exposure with sensitive equipment. By Dennis diCicco and Sean Walker, courtesy Astronomy Picture of the Day.

My former colleagues Dennis diCicco and Sean Walker (from back in my days at Sky and Telescope are first-rate astrophotographers.  I’ve seen many of their images over the years, and marvel at their skill.

So, when I saw this one, posted on Astronomy Picture of the Day, I was bowled over at the creative ingenuity – AND fantastic beauty — of their work.

This is a composite image they created using very sensitive cameras and 40 hours of exposures.  What you see here are the Orion-Eridanus superbubble region of the sky, Barnard’s Loop, and other nebulae.  This image shows objects at a level of detail that you just can’t pick up with a quick glance at the sky with your unaided eyes (or even through a telescope, for that matter.  You’d need sensitive eyes and the ability to stare at the sky for a LONG time to see this view.

Head on over to the APOD site to see the image in full-size beauty, and also with an overlay of constellation outlines.

And, while you’re at it, check out The World at Night — a website that presents images of the world’s landmarks set against the starry backdrop of the night.  It’s a great place to see stunning astro-imagery from photographers around the world. Thanks to Daniel Fischer for tweeting us about this; thanks to Dennis and Sean for their gorgeous work!