Astronomers have a mind-blowing new theory: that there are 17 billion Earth-sized planets in our galaxy. They don't yet know how many of these worlds are in habitable zones, but the implications of this discovery are amazing. So much that some claim the "quest for a twin Earth is heating up."
Simply put: If there are 17 billion Earth-sized worlds in our galaxy, it's clear that the Universe is bubbling with life.
1More
1More
Environmental Conditions in Our Solar System - National Geographic Education - 0 views
1More
Wildest Weather in the Solar System Education - National Geographic Education - 0 views
Seasons Interactive - 0 views
Lunar Phases Interactive - 0 views
HowStuffWorks "Why can we only see one side of the moon" - 0 views
earth + moon orbit - YouTube - 0 views
1More
Earth seen from the International Space Station - timelapse video | Science | guardian.... - 0 views
ISS Interactive Reference Guide - 0 views
« First
‹ Previous
261 - 280 of 294
Next ›
Showing 20▼ items per page