Orbital ATK SS John Glenn CRS-7 launch vehicle with the Cygnus cargo spacecraft bolted to the top of the United Launch Alliance Atlas V rocket is poised for launch at Space Launch Complex 41 at Cape Canaveral Air Force Station on April 18, 2017. Credit: Ken Kremer/kenkremer.com
KENNEDY SPACE CENTER, FL - The 'SS John Glenn' cargo freighter stands proudly poised for launch at pad 41 from the Florida Space Coast on Tuesday April 18, loaded with a stash of nearly 4 tons of science investigations and essential supplies atop a United Launch Alliance Atlas V rocket destined for the multinational crew aboard the International Space Station (ISS).
The lunchtime liftoff of the 'SS John Glenn' Cygnus resupply spacecraft manufactured by NASA commercial cargo provider Orbital ATK is slated for 11:11 a.m. EDT Tuesday, April 18 from Space Launch Complex 41 on Cape Canaveral Air Force Station, FL.
The US cargo ships provided by NASA suppliers Orbital ATK and SpaceX every few months act as NASA's essential railroad to space. And they are vital to operating the station with a steady stream of new research experiments as well as essential hardware, spare parts, crew supplies, computer, maintenance and spacewalking equipment as well food, water, clothing, provisions and much more.
The launch window lasts 30 minutes and runs from 11:11-11:41 a.m. EDT April 18.
Excited spectators are gathering from near and far and Tuesday's weather outlook is spectacular so far.
Blastoff of the S.S. John Glenn on the OA-7 or CRS-7 flight counts as Orbital ATK's seventh contracted commercial resupply services mission to the ISS for NASA.
The 'S.S. John Glenn' is named in honor of legendary NASA astronaut John Glenn - the first American to orbit Earth back in February 1962.
If you can't attend in person, there are a few options to watch online.
NASA's Atlas V/Cygnus CRS-7 launch coverage will be broadcast on NASA TV and the NASA launch blog beginning at 10 AM, Tuesday morning.
From a weather standpoint, Tuesday's launch outlook is outstanding at this time.
According to meteorologists with the U.S. Air Force 45th Weather Squadron we are forecasting a 90 percent chance of "go" conditions at the 11:11 a.m. EDT launch time. The primary concern is for the possibility of cumulus clouds.
The forecast calls for temperatures of 75-76° F with on-shore winds peaking below 10 knots during the countdown.
In the event of a delay for any reason related to weather or technical issues a backup launch opportunity exists for Wednesday, April 19, and also looks promising.
The AF is also predicting the same 90 percent chance of "go" conditions at launch time. With the primary concern again being for the possibility of cumulus clouds.
The rocket was rolled out to pad 41 at about 9 a.m. EDT this morning Monday April 17, in a process that takes about 25 minutes
The rocket and spacecraft passed the Launch Readiness Review held by United Launch Alliance and Orbital ATK on April 15. Launch managers from ULA, Orbital ATK and NASA determined all is ready for Tuesday's targeted launch to the ISS.
NASA/ULA Atlas V launch of Orbital ATK SS John Glenn Cygnus spacecraft on OA-7 resupply ship on April 18, 2017. Credit: ULA/Orbital ATK/NASA
The Orbital ATK Cygnus spacecraft named for Sen. John Glenn, one of NASA's original seven astronauts, stands inside the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida behind a sign commemorating Glenn on March 9, 2017. Launch slated for March 21 on a ULA Atlas V. Credit: Ken Kremer/Kenkremer.com
Orbital ATK Cygnus OA-7 spacecraft named the SS John Glenn for Original 7 Mercury astronaut and Sen. John Glenn, undergoes processing inside the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida on March 9, 2017 for launch slated for March 21 on a ULA Atlas V. Credit: Ken Kremer/Kenkremer.com
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