Even More Extra-Solar Planets

It’s difficult keeping track of this topic. Different observatories are making new discoveries, and the number of new-found planets keeps growing — to the increasing consternation of the creationists. They hate the idea that there are probably of millions of worlds out there, some of which may harbor life. The very thought is blasphemous to them, as it detracts from the glory of what their magic designer — blessed be he! — hath wrought here on earth.

Our last post on this topic was back in September: Fifty More Extra-Solar Planets Discovered. It was based on a news release from the European Southern Observatory. Their estimate was that 40% of stars similar to the Sun — Class G stars, about one in thirteen of the main-sequence stars in the solar neighborhood — have at least one planet lighter than Saturn.

But the news keeps coming. Here’s an article from about a month after that from NASA: NASA Survey Suggests Earth-Sized Planets Are Common. They say, with bold font added by us:

Nearly one in four stars similar to the sun may host planets as small as Earth, according to a new study funded by NASA and the University of California.

The Europeans said that 40% of such stars had a planet lighter than Saturn. NASA says 25% of them have Earth-sized planets. That’s a lot of potentially habitable worlds, or if not strictly habitable by us, at least they may have life of some kind. NASA’s article continues:

The study is the most extensive and sensitive planetary census of its kind. Astronomers used the W.M. Keck Observatory in Hawaii for five years to search 166 sun-like stars near our solar system for planets of various sizes, ranging from three to 1,000 times the mass of Earth. All of the planets in the study orbit close to their stars. The results show more small planets than large ones, indicating small planets are more prevalent in our Milky Way galaxy.

They may be the right size, but they orbit their stars too closely. Let’s read on:

The research provides a tantalizing clue that potentially habitable planets could also be common. These hypothesized Earth-size worlds would orbit farther away from their stars, where conditions could be favorable for life. NASA’s Kepler spacecraft is also surveying sun-like stars for planets and is expected to find the first true Earth-like planets in the next few years.

But none have been found yet. We continue:

[Andrew Howard of the University of California, Berkeley, lead author of the new study] and his planet-hunting team, which includes principal investigator Geoff Marcy, also of the University of California, Berkeley, looked for planets within 80-light-years of Earth, using the radial velocity, or “wobble,” technique.

They measured the numbers of planets falling into five groups, ranging from 1,000 times the mass of Earth, or about three times the mass of Jupiter, down to three times the mass of Earth. The search was confined to planets orbiting close to their stars — within 0.25 astronomical units, or a quarter of the distance between our sun and Earth.

But what about Earth-sized planets in the habitable zone? Here’s more:

The research provides a tantalizing clue that potentially habitable planets could also be common. These hypothesized Earth-size worlds would orbit farther away from their stars, where conditions could be favorable for life. NASA’s Kepler spacecraft is also surveying sun-like stars for planets and is expected to find the first true Earth-like planets in the next few years.

Well, okay. They’re estimating. There’s more information in that article, but we have some late-breaking news. NASA just issued a press release: NASA Announcing Kepler Discoveries at Science Conference. It says:

NASA will host a news briefing at 8 a.m. PST, Monday, Dec. 5, to announce new discoveries by the Kepler mission. … Kepler is the first NASA mission capable of finding Earth-size planets in or near the “habitable zone,” the region in a planetary system where liquid water can exist on the surface of an orbiting planet. Kepler is detecting planets and possible candidates with a wide range of sizes and orbital distances to help scientists better understand our place in the galaxy.

Ah, now perhaps we’re getting somewhere. Moving along:

The briefing will provide an update on the statistical findings since Kepler’s Feb. 1, 2011, science data release and introduce a new confirmed planetary discovery.

Skipping a lot, we’ll end with this:

A live stream of the Kepler Science Conference will be available at this link.

So you can watch the news conference live on Monday. It ought to be interesting.

Copyright © 2011. The Sensuous Curmudgeon. All rights reserved.

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