A bubble in space: Abell 39 marks the death of a star like the sun. Wind from the aging central star pushes into the surrounding interstellar gas, building up a dense shell that glows blue in this image. After 36 years of travel, the Voyager spacecraft is just now reaching the edge of the sun's own wind-blown bubble. WIYN/NOAO/NSF hide caption

toggle caption WIYN/NOAO/NSF

This artist rendering provided by NASA shows Voyager 1 at the edge of the solar system. AP hide caption

toggle caption AP

The Two-Way

Has Voyager 1 Left The Solar System?

For the past decade or so, scientists have been waiting for the Voyager 1 spacecraft to cross into deep space. New research suggests it already has — over a year ago.

Listen Loading… 2:34
  • Playlist
  • Download
  • Embed
    <iframe src="http://www.npr.org/player/embed/212704340/213402435" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">

Will we need to tread lightly, in deference to the locals, when finally do make it to Mars? Pat Rawlings/SAIC/NASA hide caption

toggle caption Pat Rawlings/SAIC/NASA

On its way to Jupiter, the Galileo spacecraft looked back and captured this remarkable view of Earth and the moon. The image was taken from a distance of about 3.9 million miles. NASA hide caption

toggle caption NASA

An artist's impression of a gamma-ray burst, a powerful jet of energy lasting from less than a second to several minutes. The most powerful events in the universe, they are thought to be mostly associated with the explosion of stars that collapse into black holes. A. Roquette/ESO hide caption

toggle caption A. Roquette/ESO

Venus on the eastern limb of the Sun captured by TRACE satellite. NASA hide caption

toggle caption NASA

13.7: Cosmos And Culture

The Venus Transit: Who Cares?

There is far deeper and far more intimate reason why the Venus transit matters and it's all about Time.

Listen Loading… 4:01
  • Playlist
  • Download
  • Embed
    <iframe src="http://www.npr.org/player/embed/154282601/154310822" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">

NPR thanks our sponsors

Become an NPR sponsor