The first alien ID chart

How would Earth look (observed by an alien astronomer) seen through geological time, from its birth to today? And how good do our instruments need to be to not miss signatures of life through Earth's evolution until now?  We generate the “spectral fingerprints” of Earth through geological times using fossil records as proxy for evolutionary stages of an exoEarths. An alien ID chart...

Paper: Kaltenegger, L et al., Spectral Evolution of an Earth-like Planet, ApJ 658, 598, 2007 http://arxiv.org/abs/astro-ph/0609398 Institute for Pale Blue Dots

Klarman Hall at sunset

Tweets from CSInst

The paper can be found here: https://t.co/fRbeqtmShM 6/6
1 hour 21 min ago
“From the exoplanets’ point-of-view, we are the aliens.” Dr. Lisa Kaltenegger (, Director,… https://t.co/fTOgBqCgvg
1 hour 22 min ago
“One might imagine that worlds beyond Earth that have already detected us, are making the same plans for our planet… https://t.co/lFv2BTM1se
1 hour 22 min ago
“Our analysis shows that even the closest stars generally spend more than 1,000 years at a vantage point where they… https://t.co/Y9h4tFH6q8
1 hour 22 min ago
"Scientists at Cornell and the American Museum of Natural History have identified 2,034 nearby star-systems – withi… https://t.co/q1eBKlLukt
1 hour 22 min ago
' Exoplanets get a cosmic front-row seat to find backlit Earth ' New research by Dr. Lisa Kaltenegger (… https://t.co/w39bjVPKge
1 hour 22 min ago