One of Three | Astra Rocket 3.0 (SCRUB)

Update 03.03.2020:

After continuous delays because of bad weather, Astra had to scrub their “One of Three ” launch attempt on March 2 at T-53 seconds. It looks like a faulty sensor on Rocket 3.0’s first stage caused the scrub. The March 2, 2020 launch date was the last day of the DARPA Launch Challenge. The scrub meant that Astra lost out on $12 million USD in prize money. In a tweet they published after the scrub, they explained that safety and complete investigation of the problem is more important to them than winning the DARPA launch challenge. By doing so, they want to increase the probability of overall success of their three-launch campaign.

In a post-scrub interview, Chris Kemp stated that Astra needs to get a new FAA licence to launch, since it will no longer be the DARPA launch challenge payload. We expect the new license approval to take one to two weeks, but no longer than a month. We do not know what the new payloads will be yet,  but we will publish a new Prelaunch Preview article as soon as we have information.

What’s all this mean?

“One of Three” is Astra’s first orbital test launch of their Rocket 3.0, and the third test launch in the company’s history. Rocket 3.0 will liftoff during its three-hour launch window that starts on March 2, 2020 at 20:30:00 UTC. The launch takes place at Astra’s pad at the Pacific Spaceport Complex in Kodiak, Alaska.

On board will be four small-sats from two different providers, inserted into a target orbit of 450 km (280 miles). Three of the four satellites are ARCE-1 networked communication satellites developed by the University of South Florida. The Prometheus military satellite is an experimental satellite developed and operated by the Los Alamos National Laboratory (LANL) for the U.S. Special Operations Command (USSOCOM). The fifth payload is a spacecraft identification beacon for the Space Object Automated Reporting System (SOARS) built by Tiger Innovations.

The Rocket 3.0 Launch Vehicle

Rocket 3.0 is Astra’s third version of their small-sat launch vehicle and the first version of their orbital rocket. With a height of 11.6 m (38 ft), a diameter of 1.32 m (4.3 ft) and a payload capacity from 50 kg up to 150 kg, it is comparable to Rocket Lab’s Electron rocket with a height of 17 m (56 ft), a diameter of 1.2 m (3.9 ft) and a payload capacity ranging from 150 kg to 225 kg.

This two-stage rocket is powered by RP-1 and LOX propellant. The first stage will make use of five battery-powered pump-fed engines, while the second stage will probably use one of those engines. Since Astra is a rather secretive company, they have not released any technical information about their engines, such as ISP or thrust. The aluminum body and tanks of “Rocket 3.0” have a similarity to SpaceX’s Starship prototype SN1, with its welded stacked rings of stainless steel.

So what about the payload?

Rocket 3.0 will carry three different payloads–for five satellites in total–into a 450 km (280 miles) sun-synchronous orbit around the Earth. On board will be three identical ARCE-1 networked communication satellites; one Prometheus experimental military satellite; and one spacecraft identification beacon permanently bolted onto the second stage.

ARCE-1

The three identical CubeSat satellites—ARCE-1A, ARCE-1B and ARCE-1C—will start an automated commissioning process after their deployment. This process includes system checks, time-delayed deployment of their antennas and solar panels, and a low-power cross-link between the satellites to transmit commissioning reports and their orbital parameters. After a successful startup procedure, the satellites will await contact from the ground station to continue operations and enter the primary mission phase.

The aim of these operations is to showcase store-and-forward message handling capability, as well as transmitting messages to predetermined ground or mobile stations. To further the autonomous nature of the satellites, on-board Artificial Intelligence (AI) systems will determine orbital state positions.  AI will then decide when to put the spacecraft into a specific flight mode to maximize energy resource efficiency.

Another interesting fact about these satellites is that University of South Florida undergraduate and graduate engineering students will operate them.

Prometheus

Space Object Automated Reporting Systems (SOARS)

ASTRA

Employees

Despite Astra being a rather young launch provider, it already employs some major space industry veterans and former SpaceX employees. Such engineers as Chris Thompson, Matt Lehman, Roger Carlson and Bryson Gentile, who were founding members, are part of the propulsion team. They worked on the Dragon capsule and on the Falcon 9, respectively.

Astra’s future goal is to become the FedEx of space deliveries in the small-sat sector by providing an easy to build transportable launch system that is cheap and simple.

DARPA Competition

Early in 2018, the Defense Advanced Research Projects Agency, also known as DARPA, started a launch contest where contestants could win a grand price of $10 million USD. Participants had to meet the following criteria:

• two separate launches
• different launch sites
• short notification to first launch
• only days to two weeks between launches
• different payloads
• different orbits

Initially, 18 teams got pre-qualified by DARPA. However, only three became finalists: Virgin Orbit’s VOX Space subsidiary, Vector Space and Astra. While Vector Space ran into financial problems, Virgin Orbit dropped out because they focused on getting their air-launch system ready for commercial operations. Therefore, only Astra remained as the final participant.

If Astra succeeds with its first orbital test launch, they will win $2 million USD with the final prize money following after their second successful launch.

Changes to the DARPA Criteria

Since DARPA originally started the challenge, it altered the criteria a bit. Astra will–for example–launch its rockets from two different pads only about 300 metres (around 1000 feet) apart. Compare that benchmark to the previous criteria of launching two rockets from two separate launch sites. Furthermore, the launches have to occur during a 14-day launch window starting on February 18, 2020 until March 31, 2020. That is a more generous window than the original criteria requiring launching two rockets only 14 days apart. DARPA determined a 450 km high target orbit for this test launch, but will also declare an orbit above 250 km as a success.