QUIZ - Due on 2.26.13

1. How do we detect planets around other stars?
• We can detect planets around other stars with the help of direct observation, astrometry, doppler shift, pulsar timing, brightness variations, and gravitational microlensing.
• DIRECTLY: Pictures or spectra of the planets themselves constitute direct evidence of their existence.
• INDIRECTLY: Precise measurements of a star's properties may indirectly reveal the effects of orbiting planets. (Almost all extrasolar planets detected to date have been found indirectly rather than through direct imagine.)
• Orbiting planets exert gravitational tugs on their star, so we can detect the planets by observing the stars resulting "wobble" around its average position in the sky.

How do extrasolar planets compare with planets in our solar system?

• Extrasolar planets compare with planets in our solar system becuase most known extrasolar planets are probably jovian. We've also found "Super Earths," likely made of metal and rock.
• Extrasolar planets (most) are more massive than Jupiter.
• Extrasolar planets (most) have different orbital characteristics than in our solar system.
• Detected planets are all way more massive than Earth.

Do we need to modify our theory of solar system formation?

• At this moment in time, we do not need to modify our theory of solar system formation. Our current theory has presented challenges, but more than a decade of re-examination hasn't resulted in any obvious flaws. In the future, the basic theory encounters & migration may play a larger role than previously thought.

What is a Hot Jupiter?

• Hot Jupiter is a class of extrasolar planets who characteristics are similar to Jupiter. They have a much higher surface temperatures because they orbit very close between approximately 0.015 & 0.5 astronimical units to their parent star.

Do extrasolar systems have a frost line?

• YES!

Define the frost line.

• Front line is a particular distance in the solar nebula from the central protosun where it is cool enough for hydrogen compounds such as water, ammonia, and methane to condense into solid ice grains.

On which side of the frost line is Earth?

• The Earth lies < than 1/4 of the distance to the frost line.

On which side of the frost line is Jupiter?

• In between Jupiter and Mars' orbits lies the Frost Lines.

What is a meteorite?

• A meteorite is a mass of stone, rock, or metal from outer space: a piece of rock that has reached Earth from outer space.

What hit Russia last Friday, February 15, 2013?

• On Friday, February 15th, 2013 a meteorite / meteoride hit Russia.