Debra Fischer

The gas-giant planets in our solar system all have large moons.

A 'serious' scientist in 1992 or 1993 had to admit the possibility that planets were really rare, that most stars might not have planets. We've gone from there to here - where most stars have planets.

Once we see stars with three times the metal content of our sun, the planet detection rate goes up to 20 per cent.

It can be very hard to know the history of a particular star, but once in a while, we get lucky and find stars with chemical compositions that likely came from in-falling planets.

There may be hundreds of small seed planets - or planetesimals - which grow in the disk of matter around a star.

Naturally, we think that finding another Earth-like planet is identifying a site that's at least friendly here for the evolution of life. The primary goal of the Kepler mission is to statistically assess the occurrence of these small terrestrial worlds.

There's no doubt that the search for planets is motivated by the search for life. Humans are interested in whether or not life evolves on other planets. We'd especially like to find communicating, technological life, and we look around our own solar system, and we see that of all the planets, there's only one that's inhabited.

Kepler's blown the lid off everything we know about extra-solar planets.

As our sensitivity improves, we are finally seeing planets with longer orbital periods, planetary systems that look more like our solar system.

Diamond planets truly are the most precious.

Our field is very focused on finding Earth 2.0, and anything we can do to narrow the search is helpful.

55 Cancri is extraordinarily rich in heavy elements and extraordinarily efficient at making planets - much more so than our sun - and those elements are the very ones you need to make planets that aren't just gas giants.

Computers can't find the unexpected, but people can when they eyeball the data.

Whether a star has planetary companions or not is a condition of its birth. Those with a larger initial allotment of metals have an advantage over those without.

We now know that stars which are abundant in heavy metals are five times more likely to harbor orbiting planets than are stars deficient in metals.

When stars form a planet, they come in a bunch.

Generally speaking, exoplanets can be any size, and they are found in a wide range of orbits. Some have massive gas atmospheres; others are smaller with an icy or rocky composition.

Ultimately, what we're looking for in the long run is to find other Earth-like planets.

It now seems logical that all the stars, like our own sun, must have formed with a system of planets around them.

Before 1995, the only planets we knew about were the planets in our solar system.

Because Alpha Centauri is so close, it is our first stop outside our solar system. There's almost certain to be small, rocky planets around Alpha Centauri A and B.

The universe has told us the most common types of planets are small planets, and our study shows these are exactly the ones that are most likely to be orbiting Alpha Centauri A and B.

Within the scientific community, there is healthy skepticism. And the question is, 'How do you ever get to a meaningful null result? How long and how hard do SETI scientists have to look for extraterrestrial intelligence and find nothing before they say, 'There is nothing. We are alone.'

Science requires speculation, creativity, and wild ideas.

The building blocks of life are readily available throughout the universe.