Does every star have planets?

According to one study, yes.

Using a technique called gravitational microlensing, an international team found a handful of exoplanets that imply the existence of billions more.

The findings were released at the 219th American Astronomical Society (AAS) meeting, alongside reports of the smallest “exoplanets” ever discovered.

Gravitational microlensing is a method that uses the gravity of a far-flung star to amplify the light from even more distant stars that have planets.

Astronomers used a number of relatively small telescopes that make up the Microlensing Network for the Detection of Small Terrestrial Exoplanets, or Mindstep, to look for the rare event of one star passing directly in front of another as seen from Earth.

The team witnessed 40 of these microlensing events, and in three instances spotted the effects of planets circling the more distant stars.

That would mean that there about bout 10 billion earth-size planets in this galaxy. Details here.

Comments

  1. #1 ToSeek
    January 12, 2012

    Yes, but there are a hundred billion or so stars in the Milky Way. Ten percent is great, but it’s a far cry from “every.”

  2. #2 F
    January 13, 2012

    ToSeek

    You’ll have to note the difference between “planets” and “earth-size planets” to get this one.

  3. #3 Greg Laden
    January 13, 2012

    I think we should just stick with “Class M”