Domagal-Goldman expects big surprises:  "We've found so many unexpected things about planets that now I expect to be amazed. Water is essential to all known forms of life on Earth. As the numbers mount, it seems to be just a matter of time before Kepler finds what astronomers are really looking for:  an Earth-like planet orbiting its star in the "Goldilocks zone"—that is, at just the right distance for liquid water and life.

There is only one planet we know of so far that is teeming with life––Earth. The basic idea is simple:  When a planet reflects the light of its parent star, the atmosphere of the planet leaves a subtle imprint on the reflection--a sort of spectral "fingerprint" that astronomers can study to learn what the planet's atmosphere is made of. What characteristics make life possible? When we can study a Goldilocks planet, I believe we'll discover something revolutionary about how life interacts with a planetary environment. Goldilocks Zone. You can find a script for the docent show Then we look at Earth: how the presence of liquid water, reflective surfaces such as polar ice caps, and the chemical composition of our atmosphere all contribute to keeping Earth's energy budget in balance. While astronomers still don't know whether there's life on other planets, they narrow the search for potentially habitable worlds using a handful of criteria. Because our blueprint for life is Earth, astronomers look for planets with Earth-like … A ScienceCast video explores the challenges of studying faraway 'Goldilocks planets.' "The possibilities," he believes, "are limitless." In this way, FINESSE can separate the planet's dim light from the stellar glare and reveal the composition of the planet's atmosphere. While planetary habitability deals solely with the planetary conditions required to maintain carbon-based life, the habitable zone deals with the stellar conditions required to maintain carbon-based life, and these two factors are not meant to be interchanged. The habitable zone is not to be confused with the planetary habitability. The Goldilocks Zone is …

How do Earth, the planets, and the heliosphere respond?Weather and Atmospheric Dynamics Focus Area Publications and Research HighlightsCarbon Cycle and Ecosystems Focus Area Publications and Research HighlightsIndia overtakes China as top emitter of sulfur dioxideLocal land subsidence increases flood risk in San Francisco BaySea surface salinity could provide new insight into severe stormsSeeing the connection between neighboring volcanoes at depthWarm ocean waters off Greenland put glaciers at more risk Short for "Fast INfrared Exoplanet Spectroscopy Survey Explorer,"  FINESSE would measure the spectra of stars and their planets in two situations: once when the planet is in view, and again when the planet is hiding out behind its star.

And on our planet, water is a critical ingredient for life as we know it. By looking within our own solar system, we identify reasons neighboring planets and our moon lack conditions for life. One new mission under consideration by NASA, named FINESSE, is a fingerprint specialist.

With NASA's Kepler spacecraft discovering alien worlds at a record pace, it seems to be just a matter of time before an Earth-sized planet is found in the "Goldilocks zone"--that is, in an orbit sized just right for liquid water and life. But finding a Goldilocks planet is just the first step. Kepler has already located a few Earth-sized planets, but they are too close for comfort to their parent stars.

"To get at that story and learn about the planet's atmosphere and composition, we can use a technique called transit spectroscopy." Most are hundreds, or even thousands, of light years away from Earth. Proximity to the Sun allowing liquid water. The docent show covers Earth's energy budget in greater depth. Light reflected from a planet carries the 'fingerprint' of its atmospheric composition. - Earth reflects an average 30% of incoming solar energy back to space- Earth's atmosphere absorbs about 20% of incoming solar energy- About 50% of solar energy reaches the land and oceans and warms them- Earth emits 70% of incoming energy back to space as heat (infrared radiation)This movie gives an overview of NASA's Search for Goldilocks Planets and can be used on its own or within a docent show as an introduction.