How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early astronomy. Ancient Greeks were able to find the size of the Earth, and from that the distance to and the sizes of the Moon and Sun. Once the Earth/Sun distance was found, parallax was used to find the distance to nearby stars, and that was bootstrapped using brightness to determine the distances to much farther stars.
Hard as it is to swallow, cutting-edge theories are suggesting that our universe may not be the only universe. Instead, it may be just one of an infinite number of universes that make up the "multiverse." In this show, Brian Greene takes us on a tour of this brave new theory at the frontier of physics, showing what some of these alternate realities might be like.
Since its formation in the early 60’s, NASA has continued to be the leading power in space exploration. Working with other space agencies, it has contributed substantially to the ongoing exploration of our universe, achieving incredible firsts that span the decades.
Finding alien life on a distant planet would be amazing news - or would it? If we are not the only intelligent life in the universe, this probably means our days are numbered and doom is certain.