Kepler Mission Discovers “Tatooine-like” Planet

Artist's rendering of Kepler-16b Image Credit: NASA/JPL-Caltech/R. Hurt

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In a news conference today, Kepler mission scientists announced the first confirmed circumbinary planet ( a planet that orbits a binary star system). The planet in question, designated Kepler-16b has been compared to the planet Tatooine from the Star Wars saga.

Would it be possible for someone like Luke Skywalker to stand on the surface of Kepler-16b and see the famous “binary sunset” as depicted in Star Wars?

Despite the initial comparison between Kepler-16b and Tatooine, the planets really only have their orbit around a binary star system in common. Kepler-16b is estimated to weigh about a third the mass of Jupiter, with a radius of around three-quarters that of Jupiter.

Given the mass and radius estimates, this makes Kepler-16b closer to Saturn than the rocky, desert-like world of Tatooine. Kepler-16b’s orbit around its two parent stars takes about 229 days, which is similar to Venus’ 225-day orbit. At a distance of about 65 million miles from its parent stars, which are both cooler than our sun, temperatures on Kepler-16b are estimated in the range of around -100 C.

The team did mention that Kepler-16b is just outside of the habitable zone of the Kepler-16 system. Despite being just outside the habitable zone, the team did mention that it could be possible for Kepler-16b to have a habitable moon, if said moon had a thick, greenhouse gas atmosphere.

Binary Sunset as seen on Tatooine
Tatooine appears to have twin stars like our sun, versus the orange (type K) and red (type M) stars of Kepler-16
During the press conference John Knoll, visual effects supervisor at ILM, mentioned: “When I was a kid, I didn’t think it was going to be possible to make discoveries like this.” Knoll also added, “The science is stranger and cooler than fiction!”

The Kepler mission detects exoplanet candidates by using the transit method which detects the dimming of the light emitted from a star as a planet crosses in front of it. In the case of Kepler-16b, the detection was complicated by the two stars in the system eclipsing each other.

The system’s brightness showed variations even when the stars were not eclipsing each other, which hinted at a third body. What further complicated matters was that the variations in brightness appeared at irregular time intervals. The irregular time intervals hinted that the stars were in different positions in their orbit each time the third body passed. After studying the data, the team came to the conclusion that the third body was orbiting, not just one, but both stars.

“Much of what we know about the sizes of stars comes from such eclipsing binary systems, and most of what we know about the size of planets comes from transits,” added Kepler scientist Laurance Doyle of the SETI Institute. “Kepler-16 combines the best of both worlds, with stellar eclipses and planetary transits in one system.” Doyle’s findings will be published in the Sept. 15th issue of the journal Science.

The Kepler mission is NASA’s first mission capable of finding Earth-size planets in or near the habitable zone – the region around a star where liquid water can exist on the surface of an orbiting planet. A considerable number of planets and planet candidates have been detected by the mission so far. If you’d like to learn more about the Kepler mission, visit: http://kepler.nasa.gov/

You can also read more about the Kepler-16b discovery at: http://kepler.nasa.gov/Mission/discoveries/kepler16b/

Source: NASA news conference / NASA TV

Ray Sanders is a Sci-Fi geek, astronomer and space/science blogger. Visit his website Dear Astronomer and follow on Twitter (@DearAstronomer) or Google+ for more space musings.

Poland “agrees” to host controversial US missile defence system

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In a controversial move likely to enflame tensions between Russia, Europe and the US, Poland has agreed (in principal) to host bases for the “Star Wars” US missile shield intended to protect against any future missile attack from rogue nations. Russia totally opposes plans, stating that a European missile system, so close to the Russian border, is akin to the Cuban missile crisis in the 1960s where the US and Soviet Union went to the brink of nuclear war…

Any space missile system intended to neutralize the threat of a nuclear attack from rogue states was bound to cause controversy and anger. As predicted, the future development of a European US missile shield has caused very loud opposition from Russian President Vladimir Putin, directly highlighting that such a move would cause another arms race and could create a nuclear standoff between Russia, US and Europe in between.

The Czech Republic is currently drawing up plans for involvement in the US project and now Poland, a country that directly borders Russia, has agreed to more discussions about installing ten interceptor missiles. The missile shield plans are in a direct response to the ongoing threat from “rogue states”, principally Iran and North Korea, from their nuclear arms development programs the US believes they are still pursuing, but understandably, Russia is suspicious that the US is attempting to gain strategic strength in Eastern Europe. Mr Putin has hinted strongly that although Russia is not planning to begin wholesale targeting of Europe, any “new targets” in the future would be connected to the “strategic nuclear potential of the United States… in Europe” (see BBC article “New era of discord for Russia and West” for full information on the new political unrest). Scary.

We understand that there is a desire for defence modernisation in Poland and particularly for air defence modernisation in Poland. This is something that we support because it will make our ally, Poland, more capable,” – US Secretary of State Condoleezza Rice, supporting the missile defence plan in Poland.

The US missile shield concept depends on European fast response missiles to be launched as soon as the threat of imminent attack is detected from aggressors in the Middle East and beyond. By detecting possible nuclear missiles clearing cloud cover and entering space, radar bases within the EU can track and then guide conventional missiles from the shield network to intercept. Tests of such a system have so far had a mix of success and failure, but with improvement of the “Star Wars” technology (a name first coined in 1983 after announcement by US President Ronald Reagan for the commencement of the “Strategic Defence Initiative”) and rocket engineering, rates of successful interception are bound to increase.

Source: BBC