Ad 1

Saturday 11 March 2023

Rocket Lab’s second launch from Virginia will loft two commercial radar satellites

This artist’s concept shows a Capella Whitney-class satellite in orbit with its solar arrays and radar reflector unfurled. Credit: Capella Space

Rocket Lab’s second mission from a new launch pad in Virginia is set to take off Saturday night with two commercial radar remote sensing satellites for Capella Space.

The company has a two-hour launch window opening at 6 p.m. EST (2300 GMT) for liftoff Saturday from the Mid-Atlantic Regional Spaceport at Wallops Island, Virginia. A 59-foot-tall (18-meter) Electron rocket will fire off the launch pad with nine kerosene-fueled engines generating more than 50,000 pounds of thrust.

The mission will be Rocket Lab’s 34th launch, and the company’s second from Launch Complex 2, or Pad 0C, on Virginia’s Eastern Shore. Rocket Lab launched its first mission from the new pad Jan. 24 with a trio of HawkEye 360 radio frequency monitoring satellites.

Capella Space, the San Francisco-based radar remote sensing company, is the customer for the second Rocket Lab flight from Virginia. There are two radar Earth observation satellites — each roughly 220 pounds (100 kilograms) — aboard the Electron rocket awaiting liftoff Saturday.

The tandem satellite launch will come close to maxing out the Electron rocket’s lift capability. The rocket can haul up to 440 pounds (200 kilograms) of payload into a 310-mile-high (500-kilometer) polar orbit, according to Rocket Lab, which has carved a niche in the global launch market for delivering small payloads on dedicated rides to low Earth orbit. Larger rockets, such as SpaceX’s Falcon 9, can carry numerous small satellites on rideshare missions, but often does not release the payloads in each customer’s preferred orbit.

The target orbit for Saturday’s mission is at an altitude of 373 miles (600 kilometers) and an inclination of 44 degrees to the equator. The two-stage, carbon fiber Electron launcher will head southeast from the Virginia spaceport, located at NASA’s Wallops Flight Facility, and take advantage of a velocity boost from Earth’s rotation, helping accelerate the two Capella satellites into orbit.

Rocket Lab started the year aiming to launch as many as 15 missions with its Electron rocket in 2023. This weekend’s flight will be the company’s second launch of the year.

At the same time ground teams are readying the Electron rocket for launch from Virginia on Saturday, Rocket Lab engineers are preparing a different Electron rocket for a mission later this month from the company’s spaceport in New Zealand. That flight will deploy two optical Earth-imaging satellites for BlackSky.

Rocket Lab has two launch pads at its privately-owned spaceport on the North Island of New Zealand, where the first 32 Electron rockets took off before the Virginia launch site entered service.

Rocket Lab’s Electron launcher on its launch pad in Virginia. Credit: Rocket Lab

During Saturday’s countdown, Rocket Lab’s launch team in Virginia will load kerosene and liquid oxygen propellants into the Electron rocket. The launch director will poll the team at T-minus 12 minutes for a final “go” or “no go” for liftoff, and the countdown’s automated sequence will begin two minutes before launch.

Nine kerosene-fueled Rutherford engines will ignite at T-minus 2 seconds, then hold-down restraints will release to allow the Electron rocket begin its climb into space. The rocket will surpass the speed of sound in about a minute, then shut off its first stage engines around two-and-a-half minutes after liftoff.

The booster will release to fall into the Atlantic Ocean. Rocket Lab does not plan to recover the first stage on Saturday’s flight.

The Electron’s upper stage will ignite its single engine for a six-and-a-half minute burn to place the Capella satellites into a parking orbit. A kick stage will separate from the Electron’s second stage, then coast halfway around the world before a final burn to inject the two payloads into their targeted 373-mile-high orbit for deployment.

According to a mission timeline released by Rocket Lab, the two Capella satellites will separate from the kick stage around 57 minutes into the mission.

Capella is one of several companies developing fleets of radar imaging satellites. After launch, the two Capella spacecraft will unfurl solar arrays and open their radar reflector antenna to a diameter of about 11.5 feet (3.5 meters), allowing the satellites to begin collecting imagery..

Capella’s satellites use synthetic aperture radar technology, allowing imagery collection night and day and in all weather conditions. Optical satellites are limited to observations in daylight and in cloud-free skies.

So far, Capella has launched eight radar imaging satellites, including a prototype not used in commercial service. The satellites on Rocket Lab’s mission this weekend will be Capella 9 and 10, and are part of the company’s Whitney spacecraft design.

SpaceX has launched seven of Capella’s eight satellites to date, and Rocket Lab has launched one Capella spacecraft. Rocket Lab and Capella announced a contract in February for another four launches beginning later this year, each carrying an upgraded satellite based on a slightly larger spacecraft platform called Acadia.

Capella, which designs and builds its own satellites, has won contracts with the National Reconnaissance Office, the U.S. Air Force, the Space Force, the Navy, and the National Geospatial-Intelligence Agency, along with imagery sales to commercial customers.

The agreement with the NRO, announced in 2022, is to demonstrate the company’s ability to deliver imagery to U.S. government intelligence analysts, including downlinks directly to overseas theaters, and to respond to requests for regional radar imagery.

The NRO owns the government’s large high-resolution optical and radar surveillance satellites, likely with higher resolution than Capella’s smaller radar remote sensing platforms. But with a fleet of radar spacecraft, Capella could supplement imagery collected by the government-owned intelligence-gathering satellites to better monitor military activity and strategic targets around the world.

The NRO has similar agreements for commercial imagery buys from other optical and radar remote sensing satellite operators.

Email the author.

Follow Stephen Clark on Twitter: @StephenClark1.



from Spaceflight Now https://ift.tt/QnFJXLE
via World Space Info

0 comments:

Post a Comment