Category Archives: astronomy

Starbirth in the Neighborhood

A Galaxy Blazes with Newborn Stars

The spiral galaxy M83 as seen by Hubble Space Telescope. Courtesy NASA/ESA

Galaxies are huge collections of stars, gas, dust, black holes, and planets. The Milky Way is a good example of a spiral galaxy. It also happens to have a bar of gas and dust and stars across its center, and many places where stars are being born. It turns that when astronomers look at other galaxies, particular spiral galaxies (and many colliding galaxies), they also see regions of starbirth.

Hubble Space Telescope has been astronomy’s “go to” machine in space when astronomers want to look at something like a distant galaxy. This Hubble image shows the pinwheel (spiral) galaxy M83, which lies in our southern hemisphere skies in the constellation Hydra. It’s about 15 million light-years away, and, as you can see here, is ablaze with starbirth regions spread across 50,000 light-years of space.

The pink blobs are the starbirth nurseries sitting on the edges of dark dust lanes. They are churning out hot young stars that are extremely bright in ultraviolet light. The UV radiation heats up surrounding clouds, and they are what we see glowing in hot pink (in this image). Those hot young stars are busily evaporating nearby gas clouds with their UV light. They emit strong winds which also disrupt their nurseries. Eventually, the starbirth crêche disappears, revealing the newborn star.  Those hot young stars live short, energetic lives—perhaps existing only about 10 million years before exploding as supernovae. When they do die this way, the blast blows huge clouds of material out to space, blowing “bubbles” in space. HST has seen nearly 300 of these death bubbles. All this activity makes M83 a great place to study the dynamics of star birth, star death, and the contributions these events make to the galaxy.

It’s not just professionals who are studying this galaxy. M83 is being used as a target for citizen science, too. The idea is to come up with estimated ages for around 3,000 star clusters in this galaxy. The project is called Star Date: M83, a collaboration between the Space Telescope Science Institute and Zooniverse, creators of several citizen science projects including Galaxy Zoo, Planet Hunters, and the Andromeda Project (go to www.zooniverse.org to see the full list). The M83 project is launched on Monday, January 13, 2014. If you’re interested in participationg, visit http://www.projectstardate.org .

What will you be asked to do? You and others will use the presence or absence of the pink hydrogen emission, the sharpness of the individual stars, and the color of the clusters to estimate ages. Participants will measure the sizes of the star clusters and any associated emission nebulae. Finally, you and your fellow citizen scientists will “explore” the image, identifying a variety of objects ranging from background galaxies to supernova remnants to foreground stars.  If you’ve never done citizen science before, it’s quite interesting to participate in. I was part of Galaxy Zoo for awhile, and the people who ran that project provided all the information we needed to start classifying galaxies by their shapes.

M83 is a gorgeous object, and I think that people who study it (professional and citizen scientists) will come away with an amazing insight into the lives and deaths of stars in this distant galaxy.

 

 

People Want to Go to Mars

What Will it Be Like?

Mars explorers in a harsh, familiar, and challenging environment. Courtesy NASA.
Mars explorers in a harsh, familiar, and challenging environment. Courtesy NASA.

I’ve been amused at the numbers of people who are so interested in going to Mars they’d sign up for a one-way trip. THAT really says something about the interest people have in the Red Planet.

No, I didn’t sign up. I thought about it. But, ultimately I ended up NOT signing up. I’d want to come back, actually and share what I saw on the Red Planet.  But, I’ve often dreamed about walking those rusty plains, or climbing Olympus Mons, or taking a jet-assisted ride over Margaritifer Chaos, or slumming it down in the depths of the Valles Marineris.

You see, Mars looks a LOT like Earth in places. Yes, there’s no life (that we know of), no flowing water, no lakes, no rivers. Yes, there’s water, but you have to work to get at it. And, you’d be working in an environment with a thin atmosphere, little UV protection, cold temperatures, and living your life in a spacesuit much of the time. Mars is damned inhospitable to our type of life. We’ll have to take a lot of steps to protect ourselves, such as living underground, walking the surface encased in a suit and so on.

Still, that possibility hasn’t stopped a LOT of people from signing up for a one-way ticket.

I wonder…what will they do? Will they be the colonists that make it somehow, despite the harsh environment and no chance of return to Earth?  If so, and they reproduce, what WILL those babies be like?

Science fiction has notable examples of what life on Mars will be like for those first folks. In Mars Crossing, writer Geoffrey Landis describes a small band of people who go to Mars on what seems to be a publicity mission. It’s a captivating story; one small detail that really stuck out for me (out of  many) was the fact that people’s hair got bleached white by the ubiquitous presence of peroxide on the surface.

Then there’s Stranger in a Strange Land, Heinlein’s classic tale of Valentine Michael Smith, the child of a pair of Mars explorers who somehow ends up inheriting and representing Mars and the Martian Old Ones. The experience of growing up on Mars with ancient Martians who are simply spirits turns the human child into a very strange person, indeed.

Kim Stanley Robinson, in his set of books Red Mars, Blue Mars, Green Mars, sets out an exploratory civilization that somehow manages to bring many of Earth’s problems to Mars, and faces a whole new set of issues.  I think these books are the closest to what human exploration (and colonization) of Mars will be like. Humans are humans. We don’t leave our problems behind when we travel.

Like everybody else, I’m going to be watching these first Mars explorers, whether they go one-way or figure out a way to do a round-trip visit. Whatever they do, it will be the trip of a lifetime. Hopefully, it won’t be the last trip in their  lifetimes. I want to see them come back and tell us what Mars is like! It’ll be like things were when explorers were first visiting new lands on Earth. They eventually reported back what they found. And, the folks who stayed home anxiously awaited word of what things were like on those faraway shores.