The Boeing built satellites are set for launch on a United Launch Alliance (ULA) Atlas V rocket.

SES ordered the 702 small platform satellites from Boeing in June 2020 as part of its C-band spectrum clearing efforts.

“The delivery of SES-20 and SES-21 marks yet another big milestone for our C-band spectrum clearing project in the U.S.,” commented SES CTO Ruy Pinto.

The satellites went through environmental testing at Boeing’s satellite factory in California, including vibration, thermal vacuum, electromagnetic interference and acoustic testing. The satellites will be in their payload fairings for launch. They have been integrated into a dual-launch configuration platform built by Boeing.

“SES-20 and SES-21 are the first commercial satellites we’ve delivered since the start of the global pandemic,” said Ryan Reid, president of Boeing Satellite Systems International. “It was challenging, but we found ways to be responsive to emerging customer demands and timelines. As a result, we went from contract signing to delivery of two satellites in little over two years.”

Image: Boeing

Atlas V: the workhorse of United Launch Alliance's rocket fleet.

The rocket is a mix of Russian and American technology, using the Russian RD-180 as the rocket's first stage engine, and is one of the most versatile rockets in the world with 20 possible configurations -- though not all variants have flown.

Stats

Height: 58.3 m (191 ft) with payload fairing, 52.4 m (172 ft) with Starliner.

Diameter: 3.81 m (12.5 ft)

Mass: 590,000 kg (1,300,000 lb)

Stages: 2 (3 with Star 48 upper stage)

Developed in the mid- to late-1990s, it is the fifth and last major version of the veteran Atlas rocket, which began flying in 1957.

Lockheed Martin designed and built Atlas V as part of the U.S. government's 1994 initiative to create an Evolved Expendable Launch Vehicle (EELV) for national security missions.

The two companies with EELV rockets -- Lockheed Martin with Atlas V and Boeing with Delta IV -- merged in 2006, creating an effective U.S. market monopoly with United Launch Alliance (ULA).

For years, the U.S. government paid ULA over $800 million annually to maintain their facilities to be ready to launch EELV missions.

Therefore, pricing of the Atlas V has varied greatly over the years, with a basic Atlas V 401 (no boosters and a single-engine second stage) costing anywhere from the high-$90 millions to $163 million USD in the 2000s and early 2010s.

Sweeping price and cost-per-launch figure reductions have occurred since SpaceX began directly competing against ULA in the 2010s.

The Atlas V’s 531 variant costs a minimum of $140 million USD.

While not the cheapest rocket on the market, the Atlas V's safety is unparalleled -- with a 100% mission success rating.

Atlas V 531

This mission will use the Atlas V 531 variant - with a five-meter payload fairing (5), three side-mounted solid rocket boosters (3), and a single engine Centaur upper stage (1).

Of this configuration's previous flights, all have launched Advanced Extremely High Frequency satellites for the U.S. Air Force.

Image: John Kraus for Supercluster

Space Launch Complex-41 is the east-coast home of United Launch Alliance’s Atlas V rocket.

The pad hosted its first launch on December 21st, 1965 and is currently being upgraded to serve ULA's Vulcan rocket no earlier than 2022.

Vulcan and Atlas V will share the pad for several years before the Atlas is retired.

From the 1960s to the 1990s, SLC-41 was used for the U.S. Air Force’s Titan III and Titan IV rockets.

It has been the launch site of many notable missions:

• the Helios probes to study the Sun
• the Viking missions to Mars
• the Voyager interstellar probes
• the Mars Reconnaissance Orbiter
• New Horizon to Pluto and Kuiper Belt
• Juno to Jupiter.

The pad will soon start launching humans on Boeing's Starliner capsule beginning no earlier than 2024.

Located on Florida’s east coast, Cape Canaveral is ideally located to allow access to a wide variety of space destinations that can be reached while safely launching over the open Atlantic Ocean so as not to endanger anyone on the ground.

The Cape currently supports the launch of four different rocket families: Atlas V, Delta IV, Falcon 9, and Minotaur.

Launches of Vulcan from ULA and New Glenn from Blue Origin are set to begin no earlier than 2024 with current schedules.

NASA's Kennedy Space Center, which occupies neighboring Merritt Island, and Cape Canaveral are often confused with each other or referred to as a single place.

They are in fact separate government installations but united as a single “Eastern Range” for launch operations.

Over its history, the spaceport has held the following names:

• Cape Canaveral Air Force Station (1949-1963)
• Cape Kennedy Air Force Station (1963-1973)
• Cape Canaveral Air Force Station (1973-2020)
• Cape Canaveral Space Force Station (2020-present)

Credit: ULA