Blastoff of the X-37B spaceplane on United Launch Alliance (ULA) Atlas V rocket with the OTV-4 AFSPC-5 satellite for the U.S. Air Force at 11:05 a.m. EDT, May 20, 2015 from Space Launch Complex-41. Credit: Ken Kremer/kenkremer.com Story updated with additional details and photos[/caption]
The X-37B, a reusable Air Force space plane launched today, May 20, from Cape Canaveral, Florida, on its fourth mission steeped in mystery as to its true goals for the U.S . military and was accompanied by ten tiny cubesat experiments for NASA and the NRO, including a solar sailing demonstration test for The Planetary Society.
The military space plan successfully blasted off for low Earth orbit atop a 20 story United Launch Alliance (ULA) Atlas V rocket on the clandestine Air Force Space Command 5 (AFSPC-5) satellite mission for the U.S. Air Force Rapid Capabilities Office at 11:05 a.m. EDT (1505 GMT) today, May 20, from Space Launch Complex-41 on Cape Canaveral Air Force Station, Florida.
The weather cooperated for a spectacular liftoff from the Florida space coast, which was webcast live by ULA until five minutes after launch when it went into a communications blackout shortly after announcing the successful ignition of the Centaur upper stage.
The exact launch time was classified until it was released by the Department of Defense this morning. Early this morning the four hour launch window was narrowed down to two small windows of opportunity.
Among the experiments for the flight are 10 CubeSats housed in the Aft Bulkhead Carrier (ABC) located below the Centaur upper stage. Together they are part of the National Reconnaissance Office’s (NRO’s) Ultra Lightweight Technology and Research Auxiliary Satellite (ULTRASat). The 10 CubeSats in ULTRASat are managed by the NRO and NASA. They are contained in eight P-Pods from which they will be deployed in the coming days.
Also aboard the X-37B is a NASA materials science experiment called METIS and an advanced Hall thruster experiment. The Hall thruster is a type of electric propulsion device that produces thrust by ionizing and accelerating a noble gas, usually xenon.
Following primary spacecraft separation the Centaur will change altitude and inclination in order to release the CubeSat spacecraft.
They are sponsored by the National Reconnaissance Office (NRO) and NASA and were developed by the U.S. Naval Academy, the Aerospace Corporation, the Air Force Research Laboratory, California Polytechnic State University, and The Planetary Society.
LightSail marks the first controlled, Earth orbit solar sail flight according to the non-profit Planetary Society. Photons from the sun should push on the solar sails.
“The purpose of this LightSail demonstration test is to verify telemetry, return photos return and to test the deployment of the solar sails,” said Bill Nye, the Science Guy), and President of The Planetary Society, during the X-37B launch webcast.
“LightSail is comprised of three CubeSats that measure about 30 cm by 10 cm.”
“It’s smaller than a shoebox, everybody! And the sail that will come out of it is super shiny mylar. We’re very hopeful that the thing will deploy properly, the sunlight will hit it and we’ll get a push.”
The Boeing-built X-37B is an unmanned reusable mini shuttle, also known as the Orbital Test Vehicle (OTV) and is flying on the OTV-4 mission. It launches vertically like a satellite but lands horizontally like an airplane and functions as a reliable and reusable space test platform for the U.S. Air Force.
“ULA is honored to launch this unique spacecraft for the U.S Air Force. Congratulations to the Air Force and all of our mission partners on today’s successful launch! The seamless integration between the Air Force, Boeing, and the entire mission team culminated in today’s successful launch of the AFSPC-5 mission” said Jim Sponnick, ULA vice president, Atlas and Delta Programs.
The two stage Atlas V stands 206 feet tall and weighs 757,000 pounds.
The X-37B was carried to orbit by the Atlas V in its 501 configuration which includes a 5.4-meter-diameter payload fairing and no solid rocket motors. The Atlas first stage booster for this mission was powered by the RD AMROSS RD-180 engine generating some 850,000 pounds of thrust and fired for approximately the first four and a half minutes of flight. The Centaur upper stage was powered by the Aerojet Rocketdyne RL10C-1 engine.
The X-37B space plane was to separate from the Centaur about 19 minutes after liftoff. The Centaur continued firing separately with the CubeSat deployment, including the Planetary Society’s LightSail test demoonstration, into a different orbit later.
Overall this was ULA’s sixth launch of the 501 configuration the 54th mission to launch on an Atlas V rocket. This was also ULA’s fifth launch in 2015 and the 96th successful launch since the company was formed in December 2006.
The OTV is somewhat like a miniature version of NASA’s space shuttles.
Boeing has built two OTV vehicles. But it is not known which of the two vehicles was launched today.
Altogether the two X-37B vehicles have spent a cumulative total of 1367 days in space during the first three OTV missions and successfully checked out the vehicles reusable flight, reentry and landing technologies.
The 11,000 pound (4990 kg) state-of -the art reusable OTV space plane was built by Boeing and is about a quarter the size of a NASA space shuttle. It was originally developed by NASA but was transferred to the Defense Advanced Research Projects Agency (DARPA) in 2004.
All three OTV missions to date have launched from Cape Canaveral, Florida and landed at Vandenberg Air Force Base, California. Future missions could potentially land at the shuttle landing facility at the Kennedy Space Center, Florida.
The first OTV mission launched on April 22, 2010, and concluded on Dec. 3, 2010, after 224 days in orbit.
The following flights were progressively longer in duration. The second OTV mission began March 5, 2011, and concluded on June 16, 2012, after 468 days on orbit. The third OTV mission launched on Dec. 11, 2012 and landed on Oct. 17, 2014 after 674 days in orbit.
The vehicle measures 29 ft 3 in (8.9 m) in length with a wingspan of 14 ft 11 in (4.5 m). The payload bay measures 7 ft × 4 ft (2.1 m × 1.2 m). The space plane is powered by Gallium Arsenide Solar Cells with Lithium-Ion batteries.
Among the primary mission goals of the first three flights were check outs of the vehicles capabilities and reentry systems and testing the ability to send experiments to space and return them safely. OTV-4 will shift somewhat more to conducting research.
“We are excited about our fourth X-37B mission,” Randy Walden, director of the USAF’s Rapid Capabilities Office, said in a statement. “With the demonstrated success of the first three missions, we’re able to shift our focus from initial checkouts of the vehicle to testing of experimental payloads.”
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
The hunt is on in the satellite tracking community, as the U.S. Air Force’s super-secret X-37B space plane rocketed into orbit today atop an Atlas V rocket out of Cape Canaveral. This marks the start of OTV-4, the X-37B’s fourth trip into low Earth orbit. And though NORAD won’t be publishing the orbital elements for the mission, it is sure to provide an interesting hunt for backyard satellite sleuths on the ground.
Previous OTV missions were placed in a 40 to 43.5 degree inclination orbit, and the current NOTAMs cite a 61 degree azimuth angle for today’s launch out of the Cape which suggests a slightly shallower 39 degree orbit. Such variability speaks to the versatile nature of the second stage Centaur motor.
There’s also been word afoot that future X-37B missions may return to Earth at the Kennedy Space Center, just like the Space Shuttle. To date, the X-37B has only landed at Vandenberg Air Force Base in California.
But there’s also another high interest payload being released along with a flock of CubeSats aboard AFPSC-5: The Planetary Society’s Lightsail-1.
The idea of using solar wind pressure for space travel is an enticing one. A big plus is the fact that unlike chemical propulsion, a solar sail does not need to contend with hauling the mass of its own fuel. The idea of using a solar sail plus a focused laser to propel an interstellar spacecraft has long been a staple of science fiction. But light-sailing technology has had a troubled history—the Planetary Society lost its Cosmos-1 mission launched from a Russian submarine in 2001. JAXA has fared better with its Venus-bound IKAROS, also equipped with a solar sail. To date, the IKAROS solar sail is the largest that has been deployed, at 20-metres on the diagonal.
Another use for space sail technology is the commanded reentry of spacecraft at the end of their mission life, as demonstrated by NanoSail-D2 in 2011.
Prospects of seeing LightSail may well be similar to what we had hunting for NanoSail-D2. Unfolded, LightSail will be 32 square meters in size, or about 5.6 meters on a side. NanoSail-D2 measured 3.1 meters on a side, and the reflective panels on the Iridium satellites which produce brilliant Iridium flares exceeding Venus in brightness measure about the size of a large rectangular door at 1 x 3 meters. Even the Hubble Space Telescope can flare on occasion as seen from the ground if one of its massive solar arrays catches the Sun just right.
The 39 degree orbital inclination angle will also limit visible passes to from about 45 degrees north to 45 degrees south latitude.
Hunting down X-37B and LightSail will push ground observing skills to the max. Like NanoSail-D2, LightSail probably won’t be visible to the naked eye until it flares. What we like to do is note when a faint satellite is set to pass by a bright star, then sit back with our trusty 15x 45 image-stabilized binoculars and watch. We caught sight of the ‘tool bag’ lost during an ISS EVA in 2009 in this fashion. There it was, drifting past Spica as a +7th magnitude ‘star’. The key to this method is an accurate prediction—Heavens-Above now overlays orbital satellite passes on all-sky charts—and an accurate time source. We prefer to have WWV radio running in the background, as it’ll call out the time signal so we don’t have to take our eyes off the sky.
Veteran satellite watcher Ted Molczan recently discussed the prospects for spotting LightSail once it’s deployed. “By then, the orbit will be visible from the northern hemisphere during the middle of the night. The southern hemisphere may have marginal evening passes. Note that the high area to mass ratio with the sail deployed, combined with the low perigee height, is expected to result in decay as soon as a couple days after deployment.”
Read a further discussion concerning OTV-4 and associated payloads by Mr. Molczan on the See-Sat message board here.
The Planetary Society’s Jason Davis confirmed for Universe Today that LightSail will deploy 28 days after launch. But we may only have a slim two day observation window for LightSail between deployment and reentry.
A deployment of LightSail 28 days after launch would put it in the June 16th timeframe.
“That’s the nominal mission time, yes,” Davis told Universe Today. “Our orbital models predict 2-10 days. For our 2016 flight, the mission will last at least four months.”
The Planetary Society plans to have a live ‘mission control center’ to track LightSail after P-POD deployment, complete with a Google Map showing pass predictions.
Satellite spotting can be a fun and addictive pastime, where part of the fun is sleuthing out what you’re seeing. Hey, some relics of space history such as the early Vanguards, Telstars, and Canada’s first satellite Alouette-1 are still up there! Nabbing these photographically are as simple as plopping your DSLR on a tripod, setting the focus and doing a time exposure as the satellite passes by.
Here’s to smooth solar sailing and clear skies as we embark on our quest to track down the X-37B and LightSail-1 in orbit.
-Follow us as @Astroguyz on Twitter, as we’ll be providing further info on orbits and visibility passes as they are made public.