NASA: There are 17 BEEELLION Earth-sized worlds in Milky Way

Plus: Kepler sniffs out 4 'potentially life-bearing planets'

Application security programs and practises

Scientists scrubbing up data about starlight from NASA's Kepler telescope have used it to estimate that there are 17 billion other Earths in our galaxy, the Milky Way.

Artist's impression of the the variety of planets being detected by NASA's Kepler spacecraft, Credit: C. Pulliam & D. Aguilar (CfA)

Artist's impression of the variety of planets found the Kepler satellite. Credit: C Pulliam and D Aguilar

Astrophysicists at the Harvard-Smithsonian Center for Astrophysics have been poring through light signals from stars in our corner of the galaxy searching for other habitable planets in the universe. Using the slight dimming that occurs when planets cross a star and partially eclipse it, the satellite-mounted telescope has been monitoring light signals from nearby stars, 2,400 of them, and a cleaned-up version of the results was presented yesterday at a meeting of the American Astronomical Society.

Francois Fressin of the Center for Astrophysics revealed that 17 per cent of stars have an Earth-sized planet in an orbit of 100 days or less. With 100 billion stars in the Milky Way, he extrapolated out that this makes for 17 billion Earth-sized planets in our galaxy alone.

Using the same stats, Fressin estimated that 25 per cent of stellar systems observed have a SuperEarth, a planet 1.25 - 2 times the size of Earth in an orbit of 150 days or less.

Larger planets are much less common. Only about 3 per cent of stars have a large Neptune (4 to 6 times the size of Earth), and only 5 per cent of stars have a gas giant (6 to 22 times the size of Earth) in an orbit of 400 days or less.

Artist's impression of the the variety of planets being detected by NASA's Kepler spacecraft, Credit: F Fressin (CfA)

Types and frequency of planets found by latest data analysis from Kepler.
Credit F Fressin

The researchers used a simulation of the Kepler survey to work out how many of the signals were noise, estimating that only a tenth were false positives after checking against some of the other ways that NASA searches for planets. Fressin says:

There is a list of astrophysical configurations that can mimic planet signals, but altogether, they can only account for one-tenth of the huge number of Kepler candidates. All the other signals are bona-fide planets.

As Kepler gathers more data, planets further away from their stars in longer orbits will become visible. The next piece of work for the telescope, and the data analysts is how many of those planets are likely to be in the habitable zones of their solar systems.

In a separate announcement, NASA announced the discovery of 461 new planet candidates. It said that four of the potential new planets were less than twice the size of Earth and orbit in their sun's "habitable zone" - meaning they could store liquid water, making them "potentially life-bearing".

The Kepler is NASA's attempt to find other habitable planets in our universe. ®

The research from the Harvard-Smithsonian Center for Astrophysics, presented at a meeting of the American Astronomical Society, has been accepted for publication in The Astrophysical Journal

Build a business case: developing custom apps

More from The Register

next story
Just TWO climate committee MPs contradict IPCC: The two with SCIENCE degrees
'Greenhouse effect is real, but as for the rest of it ...'
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
BEST BATTERY EVER: All lithium, all the time, plus a dash of carbon nano-stuff
We have found the Holy Grail (of batteries) - boffins
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
prev story


Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.