Beware the Phantom Exoplanets

June 25, 2009

This is an added complication in the search for exoplanets I hadn't thought of before: confusing exoplanets with starspots.

Yes, starspots are pretty much the same thing as sunspots; patches of cool plasma exposed by magnetic flux pushing the hotter photosphere and chromosphere aside.

Similar mechanisms drive both sunspots and starspots, and huge spots or large swarms of smaller spots have been detected on the surface of distant stars. In some cases, these starspots can be very extreme, covering a huge area of the star (up to 30% of the star's total area in some cases).

Back in 2004 however, astronomers thought they'd made quite a different discovery. Studying an exoplanet orbiting a star called TrES-1 (in the constellation of Lyra, 500 light years away), international teams of astronomers confirmed the discovery, but noted that something else was orbiting the star.

The astronomers used the transit method to detect exoplanets, meaning they measured the dip in stellar brightness as the exoplanet passed in front of the star. Exoplanets are simply too small to be resolved with telescopes (actually, that's not entirely true), so we must depend on the exoplanet blocking some of the starlight from view to signify its presence.

Although it is attractive to think there might be another exoplanet out there producing this transit effect, it turns out that the exoplanet would have to be 745AU from TrES-1 with an orbital period of 21,000 years. At these kinds of extreme distances, the exoplanet would need to be gargantuan to produce any measurable change in stellar brightness!

In a publication released yesterday, Jason Dittmann and colleagues from the University of Arizona did the legwork and worked out that the phantom exoplanet was actually a giant starspot causing the dip in brightness.

Why do I feel a tinge of sadness in the air? It's kinda cool we can detect spots on distant stars... isn't it?

Source: arXiv blog

Has the First Extragalactic Exoplanet Been Discovered?

June 15, 2009

Microlensing events are very exciting observations. In our own galaxy, we've been able to spot exoplanets using this technique, but now astronomers believe they've done the next mindboggling thing and spotted a microlensing event in a neighboring galaxy, Andromeda.

Sounds intriguing, but what is a microlensing event? How can it be used by exoplanet (indeed, extragalactic exoplanet) hunters?

Asteroid Tsunamis, Kepler's 1st Photo, Mission to Ceres (Video)

April 20, 2009

Saddle up for this week's Discovery Space Wrap Up, ladies and gents: Asteroid tsunamis aren't as bad as we thought, Kepler planet-hunting telescope sees first light, Scientists want to land on Ceres in the Asteroid Belt, and Colbert gets "treaded" by NASA:

Yuri's Night 2009? A Worldwide Space Party

April 05, 2009

Few words can really describe Yuri's Night 2009, but the best is probably "awesome." Just look at this picture... how could this not be awesome?

Ok, some other words include "a little weird," "pretty nerdy" and "boatloads of fun." But you get the idea.

The normal-looking people in there are James Williams (video producer/Friday News Feedbag regular; right), Alex Esteves (sound guy; left) and I (center).

We all went to this year's Yuri's Night -- a worldwide celebration of putting people in space -- at NASA's Goddard Space Flight Center in Greenbelt, MD.

Our mission? To document what Yuri's Night is all about, and why people volunteer their time to make it happen. So stay tuned for that... in the meantime, here are some highlights:

• Loretta Whitesides dressed as Princess Leia
• Seeing Charm City Cakes' amazing Hubble Telescope/Jupiter cake (and tasting it!)
• Yuri's Nighters getting down to a live DJ and rock band
• Interviewing a storm trooper
  

And so on. Clearly we had a blast, but you can too! Not to be a promotional advertisement for Yuri's Night, but...

The celebrations have just begun and will continue through April 12. Note that you don't have to be complete nerds like James, Alex and I to have a ridiculous amount of fun and learn a thing or two about space history in the process.

More than 170 parties going down worldwide this week, and to find one all you need to do is navigate yourself to the front page of www.YurisNight.net. There, you'll get a map of where all of the events are.

Nothing close by? Do your town a favor and start one! There's still time... click here for details.

Photos: Dave Mosher, Discovery.com

Planet-Hunter Launches, Moon Crash, Colbert for Space Station (Video)

March 09, 2009

What's in store for this week's Discovery Space Wrap Up: NASA's earth-like planet-hunting Kepler Telescope launches, China's Chang'e 1 spacecraft bites the moon dust, Stephen Colbert wants his own space station node.

Also of note is that I am working on a grotesque beard to ward off single women -- enjoy:

Science De-Stimulated(?), Amazing Spiral Galaxy, Hot 'n Rocky Exoplanet

February 09, 2009

Without any adieu, the space video for this week:

Also: If you haven't checked out this week's big Wide Angle: Mission to Europa?, click here to dig in!

Found: One Hot and Rocky Little Exoplanet

February 03, 2009

Ladies and gents, we've found the smallest-ever rocky planet outside of the solar system -- way outside of the solar system. (About 456 light-years outside, to be precise.)

Nevermind that COROT-Exo-7b is likely a place covered in molten lava and/or face-melting steam; it's still rocky and we know it (clap your hands)!

This from the press release:

"For the first time, we have unambiguously detected a planet that is 'rocky' in the same sense as our own Earth." - Malcolm Fridlund, ESA's COROT (convection rotation and transits) project scientist

This brand-new exoplanet is about half two times the diameter of Earth.*

Since hardly any of us can remember the precise diameters of solar system bodies, I whipped up this graphic for a sense of scale (I make no warranties that this is exact, but it should be close):

Solar Eclipse, Control Hubble, One Hot Exoplanet, Lakes on Titan

February 02, 2009

Your space news wrap-up for the week waits below. And I don't care what you say, but I don't look like Shia LeBoeuf:

Note 1: Speaking of solar eclipses...

If you missed the audio slide shows from 2008 total solar eclipse trip (in a ginormous plane near the North Pole), click here for part one. Then click here for part two.

Note 2: Speaking of solar eclipses (again)...

Going to Asia or the South Pacific around, say, July 22 of this year? You're in for a treat! Click here to see why.

'Super' Neptune, NASA in Obama's Parade, IYA 2009 Art, Simonyi's Second Flight

January 27, 2009

For some reason, I completely forgot to mention the Discovery Channel's new Cosmic Collisions show in this video post. D'oh. Be sure to visit the Wide Angle we put together here.

That being said, this week's video:

NASA Drama, Hot Exoplanets, the Moon and Endeavour's Return

December 16, 2008

What are the biggest things that happened in the crazy world of space last week? Well, you'll just have to watch the video to find out...