25 July 2014, 07:17 AM ET
Using observations by NASA's Kepler and Spitzer space telescopes, researchers determined that the exoplanet Kepler-93b is 1.48 times the size of Earth, allowing scientists to conclude that the planet is very likely composed of iron and rock.
25 July 2014, 07:00 AM ET
Is the moon made of green cheese? Is it a hollow spaceship? Apollo 11 helped put these and other ideas to rest.
24 July 2014, 04:34 PM ET
The Hubble Space Telescope has created the most detailed map ever of the star-filled halo encircling Centarus A, the closest giant elliptical galaxy to our Milky Way galaxy. The map reveals a surprising amount of heavy metals along the halo's outer edge.
24 July 2014, 02:44 PM ET
The cloudier an alien planet is, the closer it can get to its star and still remain potentially life-friendly, researchers say. See what it means for life on planets even as hellish as Venus.
24 July 2014, 12:06 PM ET
NASA's STEREO spacecraft captured imagery of recently discovered Comet Jacques on its nearest approach to the Sun as the object was moving at over 110,000 miles per hour. The comet can be spotted in the pre-dawn hours.
24 July 2014, 10:33 AM ET
Imagery from the Rosetta mission has been used to create a visualization of periodic comet 67P/Churyumov–Gerasimenko. The probe insert itself into orbit around the comet in the first week of August 2014.
23 July 2014, 04:56 PM ET
Scientists are still debating whether NASA's Voyager 1 spacecraft is in interstellar space, but a new study outlines a test that could definitively show where the far-flung probe is on its journey out of the solar system.
23 July 2014, 01:30 PM ET
The United States is outsourcing space exploration to other countries, something that should be a cause for concern.
23 July 2014, 01:08 PM ET
See photos from the European Space Agency's Automated Transfer Vehicle 5 (ATV-5) mission to the International Space Station in this Space.com gallery. ATV-5 is Europe's fifth and final planned ATV mission.
23 July 2014, 12:03 PM ET
NASA's first Landsat mission launched in July 1972. Seven more satellites have been launched since. Two of these, Landsat 7 & 8, are still active. The program acquired science imagery of natural disasters, urban change, water, ice, and farming.
23 July 2014, 10:20 AM ET
The agency's Chandra X-ray Observatory — one of NASA's 'Great Observatories,' along with the Hubble and Spitzer space telescopes and the now-retired Compton Gamma Ray Observatory — launched aboard the space shuttle Columbia on July 23, 1999.
23 July 2014, 08:46 AM ET
The NASA space-based telescope has delivered amazing imagery of the hidden Universe and expanded our knowledge of black holes, dark matter and the life and death of stars. It was launched on July 23rd, 1999 aboard the Space Shuttle Columbia.
23 July 2014, 06:01 AM ET
A family of bright young stars group together against a background of glowing clouds in a new photo from an observatory in the Southern Hemisphere.
23 July 2014, 06:00 AM ET
The European Southern Observatory's La Silla Observatory imaged NGC 3293, a star cluster in the constellation Carina (The Keel), a site where sibling stars grow and generations evolve.
22 July 2014, 05:50 PM ET
NASA's New Horizons' mission, which blasted off in 2006, will become the first spacecraft to orbit Pluto in July 2015. The flyby will give researchers their first good look at the distant, frigid dwarf planet.
22 July 2014, 02:57 PM ET
Created by lightning, ‘whistlers’ travel along Earth's magnetic field lines from hemisphere to hemisphere. Jupiter’s charged particles ‘sing’ across its magnetosphere (recorded by Voyager).
-- 'Whistling' Volcanic Lightning: http://goo.gl/kKhlEk
22 July 2014, 11:09 AM ET
NASA Fermi Gamma-ray Space Telescope detected a never-before-seen change in a binary star system in the constellation Sextants. The pulsar ceased its radio ‘beacon’ but started bright gamma ray emissions. This animation explains the behavior.
22 July 2014, 07:01 AM ET
The newly discovered exoplanet Kepler-421b — which crosses the face of, or transits, its host star from Earth's perspective — takes 704 days to complete one orbit. Thus, it has the longest year known for any transiting alien world.
21 July 2014, 09:35 AM ET
NASA's Lunar Reconnaissance Orbiter (LRO) snapped imagery of the site where humanity took their first steps on the moon. An animator combined the photograph with a terrain map to create a 3D model of the Lunar Module (LM) descent stage.
20 July 2014, 09:01 AM ET
Space.com was founded on July 20, 1999 on the 30th anniversary of NASA's Apollo 11 moon landing. Here, managing editor Tariq Malik recounts the last 15 years of Space.com, and the wonder of it all.
20 July 2014, 07:01 AM ET
On July 20, 1969, Neil Armstrong clambered down the ladder of the Apollo 11 lunar lander and pressed his boot into the moon's gray dirt — a simple step that stands as perhaps the most memorable moment in all of human history.
20 July 2014, 12:57 AM ET
What was your favorite space news story of the last week?
19 July 2014, 12:31 PM ET
From a cosmic rubber ducky to an experimental space plane, don't miss these amazing space images of the week for July 19, 2014.
18 July 2014, 08:19 PM ET
Naturally occurring pits and tubes, caused by ancient movement of molten rock, could provide safe harbor against meteorites, thermal shock, radiation and dust. This idea has been studied for 3 decades, but LRO images have now found real candidates.
18 July 2014, 12:40 PM ET
After refusing to fire its engines last week for a course correction, a vintage NASA spacecraft did produce a bit of thrust Wednesday (July 16), proving it still has at least some fuel left after 36 years in space.
18 July 2014, 11:00 AM ET
Fragments of Comet Shoemaker-Levy 9 struck planet Jupiter in July 1994.
18 July 2014, 07:00 AM ET
The European Space Agency's Rosetta probe has gotten its best look yet at Comet 67P/Churyumov-Gerasimenko, with which it will rendezvous early next month. And the results are surprising, researchers said.
17 July 2014, 04:00 PM ET
From July 16 to 22, 1994, more than 20 fragments of the comet Shoemaker-Levy 9 pelted Jupiter's atmosphere. It marked the first time humans had witnessed a collision between two bodies in the solar system.
17 July 2014, 03:48 PM ET
Imaged on 14 July 2014 by OSIRIS, Rosetta’s scientific imaging system, this movie compiles 36 interpolated images each separated by 20 minutes, providing a 360° preview of the complex shape of the comet.
17 July 2014, 06:50 AM ET
On July 12, for the first time ever, Curiosity photographed sparks flying from a rock blasted by the 1-ton robot's laser-sampling instrument, known as ChemCam. You can watch a video of the laser flashes here.
16 July 2014, 11:51 PM ET
Where is humanity in the search for planets beyond our solar system, and what will the next decade bring?
16 July 2014, 11:12 PM ET
A lone tree, 16 shots, and a stunning view of the Milky Way.