As 2015 comes to a close we look back at an exciting year of reaching new heights and revealing the unknown for the benefit of humankind.

2015 marks 50 years of successful NASA missions to Mars starting with Mariner 4 in 1965. Since then, a total of 15 robotic missions led by various NASA centers have laid the groundwork for future human missions to the Red Planet. The journey to Mars continues with additional robotic missions planned...

The first American woman in Space talks about her historic flight on NASA's 50th anniversary. She flew aboard Space Shuttle Challenger in June 1983 on the STS-7 mission.

NASA's New Horizons spacecraft has begun beaming back photographs of the surface of Pluto as it approaches the dwarf planet. . Report by Conor Mcnally.

Scott Kelly and his twin brother, Mark Kelly—also an astronaut—were the subjects of the study that sought to find out exactly what happens to the body after a year in space. Scott stayed on the International Space Station from March 2015 to March 2016, while Mark remained on Earth. This was the fina

Launched nearly 28 years ago, the Hubble Space Telescope has changed our understanding of the cosmos, allowing us to calculate the age of the universe and the rate at which it is expanding. Hubble has allow us to peer back to almost the origins of the universe, to locations more than 13.4 billion li...

Flying from Orlando, FL the crew recorded on video rare footage of Discovery's final launch as it embarks on STS-133.

When Wylie Overstreet set up his telescope outside on a whim, he had no idea he would inspire awe in hundreds of strangers on the streets of Los Angeles, reminding them of their common humanity.

Astronomers are combing through fresh data from the James Webb Space Telescope in a never-ending quest to find ever-more-distant galaxies. However, the observatory is still studying a variety of objects, from insanely detailed images of Jupiter to the most distant known star.

The European spacecraft Rosetta has become the first ever to catch up with a comet. It is a landmark step in a decade-long mission that scientists hope will help unlock some of the secrets of the solar system. Rosetta will accompany comet 67P/Churymov-Gerasimenko on its trip around the sun and land ...