Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: King, Steven on 21/11/2011 06:30:04

Title: Are we missing exoplanets that don't transit between us and the star?
Post by: King, Steven on 21/11/2011 06:30:04
King, Steven  asked the Naked Scientists:
   
Question:

I saw on a science show that telescopes are used to find planets around distant stars by measuring the light that star produces.  When a planet orbits the star, the light dims because some is blocked by the planet.  My question is about planetary orbits.  Is there some universal constant that says planets orbit counterclockwise and all on the same plane?

Suppose star xyz has planet abc but it's orbit doesn't allow for it to block any light to the telescope because its orbit is perpendicular to the telescope.  Is is possible we are missing a lot of planets because they do not block any light to our telescopes due to their orbit?

Steven King

What do you think?
Title: Are we missing exoplanets that don't transit between us and the star?
Post by: Soul Surfer on 21/11/2011 09:05:18
Yes we are most of them will not transit  the number we ARE seeing implies that most stars and star systems have planets
Title: Are we missing exoplanets that don't transit between us and the star?
Post by: CliffordK on 21/11/2011 09:37:00
Obviously there are many planets that are invisible to our current detection methods.  Most of the early planets detected were as big as Jupiter, or even larger.  Although, I believe some smaller planets are now being detected.  But, the ability to detect a planet the size of Earth, with a similar distance from the star is exceedingly difficult.

See the Wikipedia article (http://en.wikipedia.org/wiki/Methods_of_detecting_extrasolar_planets) for a summary of planet detection methods.  Many of which don't require a "transit" in front of a star, but rather are able to detect the presence of planets based on the wobble of stars due to planetary orbits, or even direct observation of the planets.