Earth's Solar Sentinel: 20 Years of the Solar and Heliospheric Observatory (SOHO)

Massive X-10 solar flare, detected by the joint NASA/ESA Solar and Heliospheric Observatory (SOHO) in October 2003. The Sun-watching spacecraft was launched 20 years ago, tomorrow, on 2 December 1995. Photo Credit: NASA

Almost a million miles (1.5 million km) “ahead” of Earth, looping about an elliptical orbit in the vicinity of a gravitational […]

First of 18 Mirrors Installed as Final Assembly Phase for NASA's James Webb Space Telescope Begins

The first of 18 mirrors being installed in the James Webb Space Telescope. Photo Credit: NASA/Chris Gunn

The first of 18 mirrors being installed in the James Webb Space Telescope, in the clean room at NASA’s Goddard Space Flight Center. Photo Credit: NASA/Chris Gunn

The James Webb Space Telescope (JWST) just took a big step toward reality with the successful installation of the first of its many flight mirrors. This is […]

James Webb Team Ready to Install Telescope's 18 Gold-Coated Primary Mirror Segments

A robotic arm lifts and lowers a golden James Webb Space Telescope flight spare primary mirror segment onto a test piece of backplane at NASA's Goddard Space Flight Center in Greenbelt, Md. In this image the JWST team practices the positioning that will be done on the actual telescope in the cleanroom. Dave Sime, an assembly crew chief, inspects the mirror placement from the underside of the backplane. Photo Credit: NASA/Chris Gunn

A robotic arm lifts and lowers a golden James Webb Space Telescope flight spare primary mirror segment onto a test piece of backplane at NASA’s Goddard Space Flight Center in Greenbelt, Md. In this image the JWST team practices the positioning that will be done on the actual telescope in the cleanroom. Dave Sime, […]

NASA's Curiosity Rover Approaching Active Martian Sand Dunes After Latest Drilling Completed

The edge of a dark sand dune field can be seen in this false-color Curiosity image from sol 1115. Image Credit: NASA/JPL-Caltech/MSSS

The edge of a dark sand dune field can be seen in this white-balanced Curiosity image from sol 1115 (Sep. 25, 2015). Image Credit: NASA/JPL-Caltech/MSSS

Mars is often referred to as a desert world, being bone-dry for the most part, with dust and sand blanketing most of the surface. Some regions are covered in vast […]

A Moon Falling Apart: Grooves on Phobos Are a Sign of its Eventual Catastrophic Fate

The unusual grooves on Phobos' surface, such as those on the left side of this image, are now thought to be caused by tidal stress. The large crater Stickney is in the upper portion of the image. Image Credit: NASA/JPL-Caltech/University of Arizona

The unusual grooves on Phobos’ surface, such as those on the left side of this image, are now thought to be caused by tidal stress. The large crater Stickney is in the upper portion of the image. Image Credit: NASA/JPL-Caltech/University of Arizona

Phobos is the largest of Mars’ two tiny moons, but 50 million […]

Hubble Observes Largest Group of Faintest and Earliest Galaxies Ever Seen

Hubble view of a galaxy cluster containing some of the smallest and youngest galaxies ever observed. Image Credit: NASA/ESA/HST Frontier Fields team (STScI)

Hubble view of a galaxy cluster containing some of the smallest and youngest galaxies ever observed. Image Credit: NASA/ESA/HST Frontier Fields team (STScI)

Peering ever further back in space and time, the Hubble Space Telescope has glimpsed the largest known group of the faintest and youngest primordial galaxies ever—over 250—some of which are estimated […]

'The Most Beautiful Thing': 30 Years Since Challenger's Last Successful Mission (Part 2)

In one of the final views of Challenger in space, the orbiter sails over the cloud-bedecked Earth, with the Spacelab D-1 module clearly visible in her payload bay. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

Thirty years ago, next week, Space Shuttle Challenger flew in space for the final time. Mission 61A—the ninth and last […]

'Dallas? You Mean the City?' 30 Years Since Challenger's Last Successful Mission (Part 1)

Thirty years ago, next week, Shuttle Challenger launched on her final successful mission. Photo Credit: NASA

It is a dismaying fact of history that the name “Challenger”—when spoken in relation to the second spaceworthy vehicle of NASA’s shuttle fleet—is so often associated only with the dreadful catastrophe which snuffed out seven lives on the […]

'On its Way': 25 Years Since STS-41 Sent Ulysses to the Sun (Part 2)

Mounted atop its IUS and PAM-S boosters, Ulysses departs Earth at the start of its odyssey to explore the Sun. Image Credit: NASA

Dick Richards enjoyed a sound night’s sleep on 5 October 1990. In the astronaut crew quarters at the Kennedy Space Center (KSC) in Florida, he was only hours away from commanding […]

Many Twists and Turns: 25 Years Since STS-41 Sent Ulysses to the Sun (Part 1)

Ulysses drifts serenely above Earth in the moments after deployment on 6 October 1990, 25 years ago, this week. Shortly after this image was taken, the attached Inertial Upper Stage (IUS) and Payload Assist Module (PAM)-S boosters would propel the craft faster than any previous man-made object out of Earth’s gravitational clutches. Photo Credit: […]