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Crystalline Entities Found in Distant Solar System

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Herschel Discovers Cometary Crystals around Beta Pictoris

We all know about comets in our own solar system. They’re conglomerates of ices mixed with dust and rock. As they get close to the Sun their gases sublimate, the dust is freed and that action creates dust and plasma tails streaming out behind the comet.  Astronomers see comets as repositories of information (in the form of those ices and dust particles) about conditions in the early solar system, since those materials have survived until this time. In particular, comets often contain materials that formed close to the Sun in the early history of the solar system, but then were somehow transported out to colder regions where comets seem to thrive.

This infrared view of the Beta Pictoris solar system, was obtained by ESO’s 3.6-meter telescope and the NACO instrument on one of the 8.2-meter units of ESO’s Very Large Telescope (inner region), and then subtracting the overpowering glare of the central star. The image shows a planet orbiting at roughly the same distance from Beta Pictoris as Saturn is from our own Sun, and a prominent dust disc in the outer reaches of the system. Credits: ESO/A-M. Lagrange et al.

So, it’s rather cool that astronomers have now found cometary particles  in another solar system, the young star Beta Pictoris. The European Space Agency’s Herschel space telescope detected pristine materials in the dust disk surrounding this star. Those materials match the makeup of comets in our own solar system.

Beta Pictoris hosts a gas giant planet, in addition to a dusty debris disk that will likely spawn the formation of some icy bodies similar to the worldlets that astronomers are finding in our own Kuiper Belt.

So, what’s the material made of that Herschel found? First, the mineral olivine is present in the disk around Beta Pic.  Olivine forms in protoplanetary disk material close to newly formed stars.  In our solar system we find it in asteroids and comets, and of course it’s found on Earth, too.

The data collected by the Herschel telescope allowed astronomers to calculate that the olivine crystals in the Beta Pic disk make up about 4% of the total mass of the dust found in a region that lies between 15 to 45 astronomical units from the star.  In our solar system, that extends from well beyond the orbit of Saturn out beyond the inner limit of the Kuiper Belt. The 4% number is quite similar to such solar system comets as 17P/Holmes and 73P Schwassmann-Wachmann 3.

Astronomers concluded that the olivine was originally bound up inside comets and released into space by collisions between the icy objects.  And, since since olivine can only crystallize  at a distance of not more than 10 astronomical units of the central star, finding it in a cold debris disc means that it must have been transported from the inner region of the system out to colder areas. A process called “radial mixing” could help push materials out away from the central star, and that could explain how the olivine crystals made it to the deep freeze of the Beta Pic system.  Want to read more about this find? Check out ESA’s Herschel Web page for the full story.

  Get Your Stargazing On for October!

This month’s edition of “Our Night Sky”, the star gazing video I produce for AstroCast.tv is now up for your viewing pleasure!  Check it out!

astrocast.tv, astronomy, stargazing

Skywatchers of Earth

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Look Up!

From time to time I exhort all my readers to do a little skywatching. There’s nothing like stepping outside on a clear night and just gazing at the stars and planets. I’ve been doing it for as long as I can remember, when weather conditions permit it. My stargazing began next to a house that doesn’t exist anymore, on a farm in Colorado that’s now a highway overpass. But, I still have these flashes of memory of standing there next to the house with the stone chimney soaring up to the sky, looking up at the stars overhead. I did it with my folks, usually my dad, and then as I got older, I did it with my friends and on dates with my first serious boyfriend.

Well, bunches of years have passed, and I still go out and look up. That boyfriend became my husband and we’ve carved out our careers bringing astronomy and space to the public through planetarium shows we produce, exhibits that I write, books I’ve written, and videos we’ve produced.

Stargazing’s a constant in my life. And, it’s one in a LOT of people’s lives.  I spent a lot of time in college — and afterwards — learning as much as I could about as many aspects of astronomy as I could.  Judging by the websites that link to this one, and the folks who follow me on Twitter and Facebook, there are a LOT of skygazers out there.  Maybe you’re one. If not, why not become one?  It’s pretty easy. You just step outside at night and look up!

Of course, you want a little background about what you’re seeing — and here’s where access to the Internet and the Web come in handy. There are many, many, many Websites about stargazing out there. I’m involved in at least one other site besides this one, an online “TV” show called Astrocast.TV. My contributions are to a program called The Astronomer’s Universe and a short little stargazing show called Our Night Sky. Here’s the February 2011 edition.

What do I do for Astrocast.TV?  Well, for both programs, I write and narrate the scripts, occasionally appear on-camera, and pull together imagery and starmaps and send them off to the fellow who “owns and operates” Astrocast.TV — a fellow named Rich Mathews. He’s really the show’s producer and mastermind and I supply him with the raw material for the shows, plus a script as a template to follow as he does the final show assembly, complete with music mixing, visual special effects, etc.

For example, this month, on Our Night Sky, I wrote the script, got it vetted by an astronomer friend of mine, then recorded myself voicing it over. I sent that VO, along with some music from my husband’s upcoming new album called Geodesium Stella Novus, and some star charts. Through the magic of video editing, Rich put it all together into the little program you can see all month. It covers a few of the many highlights of the February sky for both Northern and Southern Hemisphere stargazers. Of course, there’s a LOT more than I can cover in five minutes or so — but that’s the beauty of stargazing: there’s always something for you to discover on your own!

As long as I’m sending you to other Web sites for stargazing help, here are a few (of the many that I know about):

Sky and Telescope — the home page for Sky and Telescope Magazine.

Astronomy — the home page for Astronomy Magazine.

SkyWatcher’s Odyssey — a blog dedicated to sky sights, written by a stargazer in Texas named Dan Riding.
Check ’em out and do a little stargazing (weather permitting!).