April 30th Radio Show - Mercury and Venus

The April 30th radio show is now online, available here. Our tour of the Solar System continues with the two innermost planets, Mercury and Venus. I made a mistake on-air when I discussed why it is so hard to get a spacecraft from Earth to Mercury, and have added an errata to the mp3 available above, so even if you heard this show live I strongly encourage you to listen to the mp3 so you can hear the correct information. On this program, I also covered:

• News: Solar flare on Sun observed to trigger a "tsunami"-like shock wave through Sun's atmosphere as well as launch a coronal mass ejection on April 26; congratulation to Dr. Adam Riess (JHU/STScI) for being elected to the American Academy of Arts and Sciences, to the Galaxy Evolution Explorer (GALEX) team for successfully maintaining this UV telescope in space for 5 years; happy birthday to the Hubble Space Telescope, which celebrated 18 years from launch on April 27th - to celebrate, pretty pictures of 59 colliding galaxies were made public (link); assembly of the Herschel telescope, an European space-based infrared telescope, has been completed; DAMA/LIBRA experiment in Italy has claimed to directly detect "dark matter" on Earth again, other groups skeptical; shoulder motor on Mars rover Opportunity experiencing technical difficulties (link); Austria declares intention to join European Organization for Astronomical Research in the Southern Hemisphere (ESO); astronauts interviewed live by students on April 30 (link); NASA's Jet Propulsion Laboratory (JPL) to have an open house May 3-4
• Wednesday Morning Astronomer, a response to the astronomy content in Gregg Easterbrook's column "Tuesday Morning Quarterback" (available here) - yes, Gamma Ray Bursts (GRBs) are absolutely amazing but, no, I don't think a flurry of them were timed to mark the death of Arthur C. Clarke. I know it was a joke, but...
• Calendar of upcoming events in the greater Poughkeepsie/New York City area
• Mercury: Small rocky planets very close to the Sun, very poorly understood relative to many of the other planets in the Solar System since it is hard to observe and hard to send spacecraft to. NASA's recently launched a spacecraft to Mercury called MESSENGER, which has already flown by Mercury once. During this flyby, it imaged several craters which have dark rims, a crater with a shiny bottom, a crater wit radial spokes coming out of its center, and a very weak magnetic field emanating from its surface. The origins of these features are not known, and hopefully with more data obtained by MESSENGER after it enters Mercury's orbit in the March 2011 people will be able to figure it out. Also, scalloped-edge cliffs (called "lobate scarps") on Mercury's surface possible result of very thin mantle underneath Mercury's crust (link)
• Venus: Has, by far, the thickest atmosphere of any of the Rocky Planets in the Solar System. Recent results include the discovery of a variable bright haze layer, likely composed of sulfuric acid, at the top of its atmosphere whose origin is unknown; possible evidence for active volcanos on Venus's surface detected by the European Space Agency's Venus Explorer (link); Carbon Monoxide plays a more important role in atmosphere of Venus and Mars than previously thought (link); eye of a hurricane observed at the south pole of Venus observed to flicker and change shape within a matter of days (link); it is possible that Venus was created from the collision between two very large objects in early Solar System, could explain why - despite similar mass and distance from the Sun - Earth and Venus or so different (link); another possibility for these difference is lake of plate tectonics on Venus (link).

Hope you enjoyed, and thank you very much for listening. As always, please leave below or email any questions, comments, or concerns you might have.