As 2022 burns into August, the first week of the month may see two launches from the Space Coast—a United Launch Alliance (ULA) Atlas V and a SpaceX Falcon 9—within 12 hours of each other on Thursday. ULA’s “Mighty Atlas” is set to rise from Space Launch Complex (SLC)-41 at Cape Canaveral Space Force Station, Fla., during a 40-minute “window”, extending from 6:29 a.m. through 7:09 a.m. EDT.
The mission carries the sixth and final geostationary-orbiting member of the Space-Based Infrared System (SBIRS GEO-6) for the U.S. Space Force. And at 7:03 p.m. EDT Thursday, a five-times-flown Falcon 9 will launch from SLC-40, carrying the Korea Pathfinder Lunar Orbiter (KPLO), the first mission by South Korea to our nearest celestial neighbor.
The weather outlook appears generally favorable, with an 80-percent likelihood of acceptable conditions on Thursday, dropping slightly to 70 percent on Friday. “Forecast models indicate the Atlantic ridge will re-strengthen and push north of the area later in the week, bringing a return to deep easterly flow by Thursday morning’s launch window,” noted the 45th Weather Squadron at Patrick Space Force Base.
“Typically, on-shore winds bring a chance of showers, and even thunderstorms, in the morning,” it continued. “However, yet another swath of dry air is forecast to move over the area, resulting in more favorable launch weather conditions during the initial launch attempt.” The concern for Thursday centers upon isolated showers and a potential violation of the Cumulus Cloud Rule, with a slightly heightened likelihood of morning shower and storm activity in the event of a slip to Friday.
As previously detailed by AmericaSpace, SBIRS GEO-6 is ULA’s fifth Atlas V mission of 2022. The constellation of geostationary-orbiting satellites form part of a multi-billion-dollar Pentagon effort to replace the earlier Defense Support Program (DSP) network of early-warning satellites, whose ancestry dates back to the 1970s.
The SBIRS GEO-6 launch campaign formally commenced on 12 July, with Launch Vehicle On-Stand (LVOS) operations, when the 107-foot-long (32.6-meter) Atlas V Common Core Booster (CCB) was rotated upright inside the Vertical Integration Facility (VIF) at SLC-41. The core has been in Florida since late February, when it was delivered by the R/S RocketShip from ULA’s facility in Decatur, Ala., to the wharf at Port Canaveral, alongside hardware for two other missions.
A pair of 63-inch-diameter (1.6-meter) Graphite Epoxy Motors (GEM-63s), built by Northrop Grumman Corp., were affixed to the CCB on 13-14 July, following by the 41-foot-tall (12.6-meter) Centaur upper stage last Friday. Completion of this basic structural build-up of the Atlas V prepared the groundwork for the installation of the Extra-Extended Payload Fairing (XEPF)—housing the SBIRS GEO-6 spacecraft—on 26 July. Fully stacked, the Atlas V stood an imposing 194 feet (59.1 meters) tall.
Rollout of the Mighty Atlas, atop its Mobile Launch Platform (MLP), from the VIF to the SLC-41 pad surface is currently scheduled for Tuesday. “During MLP Roll operations on Tuesday, isolated storms are forecast to develop near the coast in the afternoon,” noted the 45th Weather Squadron, “before the inland-moving sea breeze concentrates activity west of I-95 later in the day.”
An on-time launch at 6:29 a.m. EDT Thursday will see the Atlas V power away from SLC-41 under more than 1.6 million pounds (725,000 kilograms) of thrust from its dual-nozzle RD-180 engine and the two GEM-63 strap-on boosters. The GEM-63s will exhaust their propellant and be discarded a little over two minutes into ascent, after which the RD-180 will continue to burn hot and hard until it too shuts down—an event labeled Booster Engine Cutoff (BECO)—at 4.5 minutes after liftoff.
This will leave the Centaur upper stage to complete the multi-hour task of delivering SBIRS GEO-6 precisely into its geostationary orbital “slot”. Three Centaur “burns” over a period of nearly three hours will pre-position the satellite in an orbit with a “high point” (or apogee) of 21,956 miles (35,335 kilometers) and a “low point” (or perigee) of 3,240 miles (5,217 kilometers), inclined 17.63 degrees to the equator.
Twelve hours after the dust has settled from the SBIRS GEO-6 launch, a five-times-used Falcon 9—probably B1052, a former Falcon Heavy side-booster reconfigured to fly “single-stick”—may launch as early as Thursday evening from neighboring SLC-40. Already delayed a couple of days, reportedly for additional checks of the booster, the KPLO primary payload represents South Korea’s first-ever voyage to the Moon.
Earlier this year, KPLO was renamed “Danuri”, a portmanteau of two Korean words for “Moon” and “enjoy”. And whilst this historic mission will undoubtedly bring great joy to the South Korean people, its evolution has been somewhat less stellar. Originally scheduled to fly in December 2020, it found itself subjected to an additional 18 months of delay when it outgrew its weight margins, ballooning from 1,200 pounds (550 kilograms) to almost 1,500 pounds (680 kilograms).
The KPLO spacecraft finally arrived at Cape Canaveral Space Force Station last month and has been put through extensive final tests and fueling, ahead of integration into its Falcon 9 payload shroud. Managed by the Korea Aerospace Research Institute (KARI), the cube-shaped KPLO will reach lunar orbit in mid-December after a travel time of 4.5 months. The mission will adopt a Ballistic Lunar Transfer (BLT) trajectory, which minimizes energy requirements and potentially saves up to 25 percent of propellant expenditure.
After being captured into an elliptical orbit, it will circularize its orbital parameters to a nominal polar orbit at an altitude of 62 miles (100 kilometers) for about a year of scientific observations. If the mission is approved for an “extended” phase of operations, it will later descend to an altitude below 43 miles (70 kilometers).
Six scientific instruments, totaling about 88 pounds (40 kilograms), are aboard KPLO. Five of them have been provided by KPLO. The Lunar Terrain Imager (LUTI) will examine potential landing sites for future missions at spatial resolutions of less than 16 feet (5 meters), whilst the Wide-Angle Polarimetric Camera (PolCam) will investigate the entire lunar surface, save for the poles.
Highly sensitive sensors aboard the KPLO Magnetometer (KMAG) will measure the magnetic strength of the lunar environment and the KPLO Gamma Ray Spectrometer (PGRS) will investigate lunar resources, including ices, rare elements and minerals, as well as mapping their respective spatial distribution. The Disruption Tolerant Network experiment (DTNPL) will demonstrate space-based communications using Disruption Tolerant Network (DTN) technologies.
And NASA’s highly sensitive ShadowCam will acquire high-resolution optical imagery of the Permanently Shadowed Regions (PSRs) of the lunar poles, thought to contain enormous ice deposits. ShadowCam will map the reflectance qualities of these PSRs each month to discern seasonal changes and examine the terrain within craters, including the distribution of boulders.
In March of last year, nine scientists from the Space Science Institute in Boulder, Colo., the University of California at Santa Cruz, the University of Hawaii at Honolulu, the Johns Hopkins Applied Physics Laboratory (JHU/APL) in Laurel, Md., the University of California at Los Angeles, the Planetary Science Institute in Tucson, Ariz., and NASA’s Marshall Space Flight Center (MSFC) in Huntsville, Ala., were selected to participate in the KPLO mission. Their research emphases range from the use of multispectral polarimetric data to distinguish and characterize suspected lunar pyroclastic deposits to examinations of the Moon’s magnetic field and from mineralogical prospecting to the modeling of lunar-ice deposits.