"Workers measured and marked in bright red the letters "MLG" at the spot where space shuttle Atlantis' main landing gear came to rest after the vehicle's final return from space. Securing the space shuttle fleet's place in history on the STS-135 mission, Atlantis safely and successfully rounded out NASA's Space Shuttle Program on the Shuttle Landing Facility's Runway 15 at Kennedy Space Center in Florida. Main gear touchdown was at 5:57:00 a.m. EDT, followed by nose gear touchdown at 5:57:20 a.m., and wheelstop at 5:57:54 a.m.
On the 37th shuttle mission to the International Space Station, STS-135 delivered more than 9,400 pounds of spare parts, equipment and supplies in the Raffaello multi-purpose logistics module that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis, which has spent 307 days in space, orbited Earth 4,848 times and traveled 125,935,769 miles."Source: NASA
Editor's note: Meg Urry is director of the Yale Center for Astronomy & Astrophysics and the chair of the Yale physics department. Her nearly three-decade career of space study includes a 14-year stint at the the Space Telescope Science Institute, the home of the Hubble Space Telescope, where she headed the Space Science Selection Office, sifting through thousands of applications from scientists each year hoping to use the telescope. This piece was written in association with The Op-Ed Project, an organization seeking to expand the range of opinion voices to include more women.
(CNN) - Atlantis, the last space shuttle, returned to Earth on Thursday and will go to its post-retirement gig at the Kennedy Space Center Visitor Complex. After more than 30 years and 135 shuttle flights by literally hundreds of astronauts, NASA has reason to be proud.
But for any terrestrial mourners out there, I have some tissues and another perspective: It's time.
The shuttle is an aging workhorse that should be put to pasture - it's time for a new direction for the space program.
The private sector should take over routine spaceflight while NASA develops new, more technologically current vehicles that can carry human explorers well beyond low Earth orbit.
Just as importantly, NASA should continue its wildly successful program of robotic space science, which has returned an incredible wealth of knowledge for pennies on the human-spaceflight dollar.FULL STORY
Every Friday, @CNNLightYears will suggest interesting and exciting space and science Twitter accounts to follow.
Today, @CNNLightYears is giving a #FollowFriday to the Smithsonian Institution, the world's largest museum and research complex. The Smithsonian Institution includes 19 museums and galleries, nine research centers, and the National Zoo.
The official account of the Smithsonian Institution tweets about exhibits and history tidbits, as well as interacts with museum goers.
The Smithsonian Institution National Air and Space Museum tweets about historical events, posting "today in . . ." tweets. @airandspace also shares current museum events like Mars Day (which just so happens to be today).
Chandra X-Ray Observatory tweets about new findings from studying black holes, stars, and clusters of galaxies. Follow @chandraxray for tweets about new discoveries and explanations of our universe.
The Smithsonian National Zoological Park tweets about its huge collection of animals, such as the zoo's first whooping crane since 1923. @NationalZoo also lets followers know about live zoo cameras, such as the one that shows seven black-footed ferret babies.
The Smithsonian National Museum of Natural History lets followers know about exhibits, offering "Daily Dose of Science" and "Fun Fact Friday" tweets.
For a list of all Smithsonian Institution Twitter accounts, click here.
You can also follow Twitter updates from @CNNLightYears.