German imaging satellite gets top billing on next SpaceX rideshare launch

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The EnMAP spacecraft at its factory in Bremen, Germany. Credit: OHB/H. von der Fecht

A $330 million German hyperspectral Earth-imaging satellite will hitch a ride to orbit from Cape Canaveral with 39 smaller commercial payloads on a SpaceX Falcon 9 rocket set for blastoff Friday.

The German observation satellite — named the Environmental Mapping and Analysis Program, or EnMAP — is sitting on top of a stack of microsatellites, CubeSats, and even smaller “picosats” ready for launch at 12:24 p.m. EDT (1624 GMT) Friday.

The mission is SpaceX’s fourth dedicated rideshare launch, called Transporter 4, carrying a flotilla of payloads for commercial startups and foreign governments. The 40 payloads on the Transporter 4 mission include spacecraft of various sizes, plus “non-deploying hosted payloads and an orbital transfer vehicle carrying spacecraft to be deployed at a later time,” SpaceX said.

EnMAP is the biggest of the bunch, weighing roughly 2,160 pounds (980 kilograms) and about the size of a compact car, dwarfing its co-passengers on the Transporter 4 mission.

The EnMAP project is managed by DLR, the German space agency, which first approved the satellite for development in 2006. The launch of EnMAP has been delayed a decade due to technological and engineering problems, mainly associated with the satellite’s sophisticated imaging instrument.

The satellite will scan Earth’s surface with a telescope and dual spectrometers tuned to see sunlight reflected off the ground, lakes, rivers, and oceans in 242 colors.

“EnMAP is a satellite that acquires images of Earth,” said Sebastian Fischer, the mission manager at DLR. “However, an image is normally recorded in three different colors: red, green and blue. The unique thing about EnMAP is that it does not only concentrate on these three colors, but the light is split into very many, very small wavelength ranges.”

The extra detail can tell scientists, policymakers, businesses, farmers, and foresters about the state of the environment, giving insights about the health of vegetation and water pollution.

With EnMAP, “we have a separate image for each wavelength range, which we can then analyze,” Fischer said. “And we can detect, for example, if a plant does not have enough water, or if the plant is missing nutrients.”

The EnMAP spacecraft and its hyperspectral imaging instrument were built by the German space company OHB. Originally, the plan was to send EnMAP aloft on a dedicated flight on a smaller rocket, such as India’s PSLV or the European Vega launcher, Fischer said.

But SpaceX’s rideshare program offered EnMAP a ride to space at the right time.

“In a moment where the launcher market is not too easy to get a quick launch ready for your mission, we were able to find with SpaceX a launch service that was fitting perfectly to our schedule, and that was one of the main reasons for the connection,” Fischer said.

None of the other rockets on the commercial launch market offered a flight that fit EnMAP’s schedule.

“We prefer to get it launched as soon as possible rather than delaying the program even further,” Fischer said in an interview with Spaceflight Now.

SpaceX announced its small satellite rideshare launch service in 2019. It launched the first Transporter mission on Jan. 24, 2021, with a record 143 satellites on a single rocket. The Transporter 2 mission on June 30, 2021, carried 88 payloads into orbit, and Transporter 3 launched Jan. 13 with 105 spacecraft.

The manifest for Transporter 4 is down to 40 spacecraft, but that’s primarily due to EnMAP’s presence on the mission. The satellite is heavier than any of the satellites SpaceX has flown on any of the previous Transporter missions, and the Falcon 9 will deliver EnMAP to an orbit 404 miles (650 kilometers) above Earth, higher than the the past rideshare launches.

The satellites riding on SpaceX’s Transporter 4 rideshare mission during encapsulation inside the Falcon 9 rocket’s payload fairing. Germany’s EnMAP satellite is seen on top of the stack. Credit: SpaceX

SpaceX intends to launch as many as four dedicated ridehsare flights on Falcon 9 rockets this year, doubling the rate of Transporter launches from about one every six months to one every three-to-four months.

There’s high demand for the rideshare launch service. Several SpaceX customers have said the price for a slot on a Transporter mission is unmatched in the launch industry.

On its website, SpaceX says it charges customers as little as $1.1 million to launch a payload of 440 pounds (200 kilograms) on a dedicated rideshare flight to sun-synchronous orbit. The price is enabled by cost reductions from reusing Falcon 9 rocket hardware.

Earlier this month, SpaceX hiked its rideshare launch prices by 10%, from $1 million to $1.1 million for a 440-pound payloads, blaming “excessive levels of inflation.” The company raised its standard dedicated Falcon 9 launch price from $62 million to $67 million for the same reason.

Fischer declined to disclose SpaceX’s launch price for EnMAP, but said the expense was included in the mission’s total budget of about 300 million euros ($330 million), which also includes five years of operations in orbit. EnMAP’s budget was originally set for 90 million euros.

The EnMAP spacecraft arrived at Cape Canaveral from Germany in late February aboard a Russian Ilyushin Il-76 cargo plane, touching down in Florida a few days before the U.S. government banned Russian aircraft from U.S. airspace after Russia’s invasion of Ukraine.

Engineers verified the spacecraft weathered its trans-Atlantic journey, then loaded EnMAP with hydrazine fuel in mid-March.

“It was a bit of a challenge to get EnMAP on a rideshare mission because it’s big satellite with a lot of stuff that we needed to do at the launch site to check all the functions of the satellite,” Fischer said. “But I have to say everything went very smooth. The whole launch campaign was not delayed by one day.”

SpaceX encapsulated EnMAP and its 39 co-passengers inside the Falcon 9 rocket’s payload fairing last week, then integrated the payload compartment with the test of the launcher. Ground teams rolled the Falcon 9 from its hangar to pad 40 at Cape Canaveral Space Force Station, then raised the 229-foot (70-meter) rocket vertical Thursday afternoon.

An automated countdown sequencer will oversee loading of kerosene and liquid oxygen propellants into the rocket Friday, with countdown clocks set for an instantaneous launch opportunity at 12:24 p.m. EST.

But there’s just a 30% chance weather at Cape Canaveral will be acceptable for liftoff Friday. The changes improve Saturday, when there’s a 50% chance of favorable weather for launch.

Once off the ground, the Falcon 9 will head southeast over the Atlantic Ocean, then turn south to fly along the east coast of Florida, then over Cuba and the Caribbean Sea to place its 40 spacecraft passengers into polar orbit.

The rocket’s first stage will shut down its nine Merlin main engines and separate from the Falcon 9 upper stage about two-and-a-half minutes into the mission. While the upper stage fires into orbit, the booster will fall back into the atmosphere tail first, using periodic engine burns and hypersonic grid fins to guide itself toward SpaceX’s drone ship parked in the Atlantic Ocean southeast of Miami and west of the Bahamas — about 330 miles (530 kilometers) downrange from Cape Canaveral.

The reusable rocket, numbered B1061 in SpaceX’s fleet, will land on the drone ship 10-and-a-half minutes after liftoff to conclude its seventh trip to space.

SpaceX’s Falcon 9 rocket on pad 40 at Cape Canaveral, ready for liftoff on the Transporter 4 mission. Credit: Michael Cain / Spaceflight Now / Coldlife Photography

The second stage engine will switch off moments before the first stage lands on the drone ship, setting the stage for deployment of the EnMAP spacecraft 14 minutes into the mission.

“EnMAP will be the first satellite that is separated because we want to make sure we limit the structural loads during separation of the other satellites,” Fischer said. “That was very important for EnMAP, that we be the first ones (to separate). So we’ll be taken to our orbit at 650 kilometers, and then we will be separated.”

EnMAP is scheduled to establish radio contract with German ground teams through a tracking station in Svalbard, Norway, about an hour after separating from the Falcon 9, according to Fischer.

After two weeks of checkouts and activations, EnMAP’s instrument will be calibrated and commissioned before the satellite begins its operational mission in the September timeframe.

Capable of collecting spectra in visible and infrared light bands, EnMAP will see details of Earth’s surfaces invisible to the human eye, closing a gap in Earth observation missions, according to Walther Pelzer, head of DLR and a member of DLR’s executive board.

“We are then able to determine the fingerprints of different materials, or behavior of certain surfaces, especially natural surfaces, so agriculture and forests,” Fischer said.

The data could tell farmers where to irrigate or fertilize their crops, and identify the types of crops being grown in fields around the world, within boxes as small as 100 feet (30 meters).

“This information is obviously important in order to be able to secure the food situation in the future with an increasing world population,” Pelzer said.

The mission will also measure algae growth and pollution in inland and coastal waters.

EnMAP data will be released to scientists within a few days, and free of charge. The mission is not designed to continuously observe, but it can take data over the same region as often as every four days, using the spacecraft’s ability to point 30 degrees either side of its ground track.

Once EnMAP is off the Falcon 9, the rocket will deploy two other payloads:  spacecraft named LEO-1, whose owner has not been publicly identified, and the GNOMES 3 radio occultation atmospheric monitoring satellite for a Colorado-based company named PlanetiQ.

Two more brief engine burns by the Falcon 9 upper stage will lower the rocket’s altitude to about 310 miles (500 kilometers), and adjust the orbit’s inclination of 97.9 degrees to 97.4 degrees to the equator. The rest of the Transporter 4 payloads will separate from the rocket in that orbit.

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Follow Stephen Clark on Twitter: @StephenClark1.

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