TODAY'S TWD: EPSILON ERIDANI

I saw that today is the feast day for St. Winifred, but I already wrote about her while I was deep into watching the 'Cadfael' series. So instead, we're getting a special guest appearance:

Dan Vergano wrote this article for USA Today last week:

Star Trek fans, take heart — Mr. Spock's fabled home star, the nearby Epsilon Eridani, could harbor an Earth-like planet.
NASA astronomers today report that the triple-ringed star has an asteroid belt and a Jupiter-like giant planet in roughly the same orbits as in our own solar system. Only 850 million years old, a fifth the age of Earth's sun, Epsilon Eridani resembles a younger twin to our solar system. About 62 trillion miles away, it is the closest known solar system.

It was borrowed by the creators of the TV series 'Star Trek' as the location of Vulcan, the planet that gave us the super-logical science officer Mr. Spock.

"We certainly haven't seen it yet, but if its solar system is anything like ours, then there should be planets like ours," say astronomer Massimo Marengo of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

The NASA Spitzer space telescope results, which measure the infrared heat given off by dust and ice rings circling the star, suggest Epsilon Eridani possesses three jumbo worlds, revealed by dust-free circular lanes in its asteroid belt and more distant comet belts.The circular asteroid belt that, like ours, orbits within 300 million miles of the star is particularly surprising, Marengo says, because earlier studies had suggested the star's Jupiter-like planet followed a looping path that would have destroyed the narrow belt. Instead, it must follow a nearly circular orbit.

Because Epsilon Eridani is smaller, dimmer and younger than the sun, the "habitable zone" for Earth-like planets there is closer to the star, says planetary theorist Sean Raymond of the University of Colorado-Boulder. "An Earth-like planet could actually form in the (star's) habitable zone," he says, if the report of a well-behaved Jupiter-sized planet bears out.

Another planetary theorist, Alan Boss of the Carnegie Institute of Washington (D.C.), is doubtful, suggesting such a planet is "likely to be too massive and too close to allow Earth-like planets to form in the habitable zone."

Jokes Marengo: "Of course there is disagreement among Star Trek fans about whether the planet of Mr. Spock could be at Epsilon Eridani, because it is such a young star and Vulcans are supposed to be an advanced civilization."

Well, maybe their ancestors moved there!

From Wikipedia:

Epsilon Eridani (e Eri / e Eridani) is a main-sequence K2 class star. It is the closest star in the constellation Eridanus, as well as the third closest star visible to the naked eye. This star has an estimated age of less than a billion years. Because of its relative youth, this star has a higher level of magnetic activity than the Sun and its stellar wind is an estimated 30 times as strong.
The rotation period is a relatively rapid 11.1 days, although this varies by latitude. Epsilon Eridani is both smaller and less massive than the Sun, with a lower level of metallicity, or elements with a higher atomic number than helium.

In 2006, a planet was suspected in orbit around this star, although the discovery is not yet secure enough to convince all planet hunters due to noise in the data. If the planet exists, it completes an orbit every 2502 days at a mean distance of 3.4 Astronomical Units (505 million kilometers) from the star. As of 2008, Epsilon Eridani is the nearest star to the Sun that is known to have a planet. The star also has two orbiting asteroid belts, one at approximately 3 AU, the second at around 20 AU, and perturbations in this material may be caused by an unconfirmed second planet. It also appears to have a Kuiper belt. The density of orbiting material, which is considerably more than that around the Sun, corroborates the star's suspected youth.

Due to it being a relatively close and Sun-like star, Epsilon Eridani regularly appears in science fiction. In the television series Babylon 5, the space station itself orbits the third planet (Epsilon 3) in this system. Gerry Anderson's television show Space Precinct is set on a planet in the "Epsilon Erandi" system, which may be an error for Epsilon Eridani.

Or as one Welsh blogger said about the star:

Mae Epsilon Eridani b yn blaned sy'n cylchio'r seren Epsilon Eridani (neu 'Al-Sadirah') yng nghytser Eridanws.Mae Al-Sadirah yn perthyn i'r un dosbarth o sêr fel yr Haul, er ei bod yn seren oren sydd ychydig yn fwy. Mae hi 10.5 o flynyddoedd goleuni i ffwrddd, sydd yn neud y blaned y mwyaf agos at y Ddaear o ran pellter.

Mae ei chrynswth 1.5 gwaith yn fwy na Iau. Mae hi'n cymryd dros 2000 o ddyddiau i gylchio Al-Sadirah, ac mae gwyddonwyr yn gobeithio y bydd hi'n cyrraedd pwynt ym mis Rhagfyr pan fydd yn bosib i'w gweld yn fwy manwl.

Gellir gweld sut mae'r nefoedd yn edrych oddi ar y blaned ei hun YMA.

But then, everybody knows the Welsh are aliens anyway.

Uh oh.....

Keep watching the skies while I go duck and cover!

BCnU!

Toby O'B