The Aug. 29 Cape Canaveral, Fla. launch of a United Launch Alliance (ULA) Atlas V 551 configuration rocket carrying sensing payloads for the National Reconnaissance Office (NRO) and U.S. Space Force NROL-107 SILENTBARKER program is to be the last Atlas V launch for NRO.

ULA is a joint venture between Lockheed Martin [LMT] and Boeing [BA] and began in December 2006.

“This is our ‘bruiser’ configuration of the Atlas,” Tory Bruno, the president of ULA, told reporters on Aug. 28 regarding ULA’s part in the NROL-107 mission. “That means it’s got five solid rocket motors on it.  When you hear, ‘4, 3,2,1, ignition,’ do not blink because it will leap off the pad. We’ll be pulling more than a G before we clear the top of that tower. About a minute and a half in, we’re gonna have fully expended half a million pounds of the solid propellant. We’re gonna drop those solids off. At three and a half minutes, we’ll have crossed the Karman line with the first stage and be all the way into space. We’ll let go of the payload fairing at that point, and a minute later we’ll be entering the LEO [low Earth orbit] regime on the booster at over 20,000 miles per hour. We’ll hand it off to the Centaur [upper stage]. It will conduct a whole series of very complex orbital maneuvers to put this payload directly injected into a high energy orbit. My rocket scientists love this mission because it is what Atlas was designed to do, and no other rocket does it better.”

The Karman line–the beginning of space more than 60 miles above mean sea level–is named for physicist, Theodore von Karman.

Bruno said that ULA has done 97 national security space missions. The NROL-107 mission is to be ULA’s 34th launch for the NRO since 2006.

The Space Force’s USSF-51 launch next year is to be the last national security space launch for Atlas V.

The successor to Atlas V is to be ULA’s Vulcan rocket, which is to launch for the first time late next year. “Vulcan will have more capability than Atlas [and] a little bit more than Delta IV Heavy in the single stick,” Bruno said on Aug. 28. “We’ll continue on in the great legacy of Atlas. In a way, it’s kinda like an Atlas VI.”

The SILENTBARKER satellites are to be an exponential leap in indications and warning for the U.S. Space Surveillance Network (SSN), which includes the 1980s-era Ground-Based Electro-Optical Deep Space Surveillance (GEODSS) telescopes and cameras at Socorro, N.M., Maui, Hawaii, and the island of Diego Garcia; about 30 ground-based radars, including the RTX [RTX] Globus II in Vardø, Norway; four Northrop Grumman [NOC] Geosynchronous (GEO) Space Situational Awareness Program (GSSAP) satellites, launched between 2014 and 2016; and two GSSAP birds launched on Jan. 21 last year.

The primary, new ground-based space tracking system is to be the $1.6 billion Space Fence radar system by Lockheed Martin–a system that is to track objects mostly in LEO but also in GEO. Located on Kwajalein Atoll in the Marshall Islands, the solid-state S-band radar system achieved initial operational capability on March 27, 2020.

NRO Director Chris Scolese told reporters on Aug. 28 that the nascence of SILENTBARKER was “about five years ago” when the NRO and the Department of the Air Force “realized we needed a better understanding of what was going on in the GEO belt.”

Development of the SILENTBARKER satellites took three years, he said.

“Today, we primarily rely on our ground-based radars,” Lt. Gen. Michael Guetlein, the head of Space Force’s Space Systems Command, told reporters on Aug. 28. “Our ground-based radars are pretty exquisite, but they can only see about a basketball size object in space, and because of the challenges of day/night/and weather, it gets extremely hard to maintain custody of those objects so by moving the sensor into orbit, we can not only detect smaller objects but maintain custody of them and when they operate out of the norm, we get indications and warning that there’s something here. That helps us to maintain in a contested environment that we can understand when our high value assets–think of strategic missile warning that’s also up there–might be in harm’s way, and that we need to take a different action.”

Guetlein said that the exponential increase of SILENTBARKER over the current SSN is “not necessarily [in] the size of the object, but maintaining all weather day/night capability and being able to maintain 100 percent custody of those objects as they maneuver in and around GEO.”