Astra is gearing up to launch the first of three consecutive missions for NASA this weekend at Cape Canaveral to deploy six shoebox-sized hurricane research satellites, developing a new paradigm of riskier but cheaper science missions.
The commercial launch company, targeting the burgeoning small satellite industry, won a $7.95 million contract last year to launch NASA’s six TROPICS spacecraft into orbit using three rockets.
The first of the three TROPICS missions is scheduled to launch during a two-hour window opening Sunday at noon EDT (1600 GMT). Forecasters are predicting stormy weather at the launch site, with a greater than 50% chance that conditions could prevent the launch. According to the official weather forecast for the launch, conditions should improve on Monday.
Astra delivered the rocket from its California plant on Florida’s Space Coast last month, then completed a test fire with the booster’s five engines at Space Launch Complex 46, a commercially operated facility near the easternmost portion of the Cape Canaveral Space Force Station. .
The first two TROPICS satellites are mounted in a launcher atop the 13.1-meter-tall Astra launch vehicle, which the company calls Rocket 3.3 or tail number LV0010.
“We’re trying to get better observations of tropical cyclones,” said William Blackwell, principal investigator of the MIT Lincoln Laboratory’s TROPICS mission. “And what we’re really trying to characterize is the basic thermodynamic environment around the storm. So those are things like the temperature, and the amount of moisture and precipitation intensity, and the structure around the storm.
“Those are important variables because they could be related to storm intensity, and even potential for future intensification,” Blackwell said in an interview with Spaceflight Now on Friday. “So we try to do those measurements with relatively many repetitions. That’s really the main new feature that the TROPICS constellation offers is an improved return of the storms.
“We’ll have six satellites in orbit, and one satellite will work to get a nice picture of the storm, and then the next satellite will orbit right behind it about an hour later,” Blackwell said. “So we’re getting a new picture of the storm about every hour, and that’s about a factor of five to eight better than what we’re getting today. With these new measurements of rapidly updated images, we hope this will help us better understand the storm, and ultimately lead to better predictions of hurricane path and intensity.”
TROPICS stands for Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats. The mission will cost about $30 million in total, according to NASA.
Each TROPICS satellite has a single instrument. A microwave radiometer, about the size of a coffee cup and spinning 30 times a minute, takes images of tropical cyclones, collects temperature readings and collects vertical profiles of moisture through the atmosphere.
“L love TROPICS just because it’s a bit of a crazy mission,” said Thomas Zurbuchen, head of NASA’s Science Mission Directorate. “Think of six CubeSats doing science looking at tropical storms with a 50-minute recurrence.”
“NOAA and the Europeans and many others have been flying passive microwave radiometers for decades, and these are big, expensive instruments,” Blackwell said. “What we’ve done with TROPICS is miniaturize the electronics to make them much smaller.
“The whole satellite for TROPICS, one of them weighs about 10 pounds and is about the size of a loaf of bread,” Blackwell said. “So these are relatively cheap to build and test, and we can make them pretty quickly, and they’re relatively cheap to launch.”
The TROPICS satellites were built by Blue Canyon Technologies in Boulder, Colorado. Their small size makes them a good match for the Astra, which can deliver about 50 kilograms of payload in an orbit 500 kilometers high. Astra’s rocket is the smallest orbital-class launcher currently flying.
Astra will launch two TROPICS satellites simultaneously and conduct missions at several week intervals. If all goes well, launches should be complete by the end of July.
The satellites will launch into Earth orbit 357 miles (550 kilometers) above Earth and orbit the planet at an angle of 29.75 degrees to the equator. The low-inclination orbit will focus TROPICS observations on hotspots for tropical cyclone development.
The second and third TROPICS launches — currently scheduled for late June and mid-July — aim to place the next four satellites in precise orbital planes, giving the constellation the correct distance to allow for regular flyovers from cyclones.
Many CubeSats travel to space during rideshare launches, allowing operators to take advantage of reduced costs by bundling their payloads onto a single large rocket. But the TROPICS satellites need special launches to reach their precise orbital destinations.
“We want to keep the spacecraft as far apart as possible and keep them above the tropical cyclone belt,” Blackwell said. “This general configuration allows us to do that, but it takes three separate dedicated launchers.”
According to NASA, Astra beat the bids from SpaceX, Rocket Lab, Virgin Orbit and Momentus, largely because of their cheaper proposal.
“NASA chose Astra because of our unique ability to get into three different orbital planes in a very short time and at a low cost,” said Martin Attiq, Astra Chief Business Officer. “So it’s unprecedented to be able to launch three different times for $8 million.”
Founded in 2016, Astra aims to eventually launch daily missions to launch small satellites into orbit for a range of clients, including the US military, commercial companies and NASA. The company has successfully completed orbit in two of its six attempts.
Astra’s most recent flight in March marked the first time the company had placed functioning satellites in orbit, following a launch from Kodiak Island, Alaska. The previous February launch of the Astra, which departed from Cape Canaveral, failed to launch a NASA-sponsored CubeSats into orbit.
NASA officials are aware of the risk of flying satellites on a new, relatively unproven launch vehicle. TROPICS is part of NASA’s Earth Venture program, a series of limited missions designed for Earth science research. NASA takes more risk for Venture-class missions.
“Only four of the spacecraft have to work, so two rockets should work,” Zurbuchen said. “This is a different level of risk than what we do in so many other things where we focus a little bit, smooth the risk and lower it as much as possible. And that’s deliberate. It’s deliberate, because speed is important when you’re in the innovation game.” and we want new capabilities, new resources and new tools.”
NASA selected TROPICS for development in 2016.
“We designed the mission from the ground up to build toughness to fail,” Blackwell said. “The choice for six satellites was made to give us some margin. We only needed four to meet our baseline requirements, so we can tolerate satellite failure or launch failure, or whatever, and we can still meet our requirements.”
Astra’s first launch with two TROPICS satellites will begin with the ignition of Rocket 3.3’s five kerosene-powered engines on pad 46. The Delphin engines will propel the launcher off the pad with 32,500 pounds of thrust, propelling the rocket eastward. . northeast of Cape Canaveral.
The engine shutdown of the first stage is expected three minutes after launch, followed by the separation of the rocket’s charge shell, which covers the upper stage and the TROPICS charges as it climbs through the atmosphere. Then the rocket’s booster stage will be jettisoned to fall into the Atlantic Ocean, allowing the top stage to ignite for a five-minute burn to accelerate to orbital speed.
Deployment of the TROPICS satellites is scheduled for T+plus 8 minutes 40 seconds, according to a mission timeline posted by Astra.
The satellites will deploy solar panels to generate electricity, and ground teams will guide the TROPICS spacecraft through tests and checkouts.
If the three TROPICS launches go off the ground as planned, the satellites should all be assembled by August, just in time for the height of the Atlantic hurricane season, according to Will McCarty, NASA’s program scientist for the mission. The mission is designed for a minimum of one year of scientific observations.
“We’re obviously very motivated to get the data out as soon as possible because we’re in the throes of the Atlantic hurricane season, so there’s going to be a lot of demand for that data,” Blackwell said. †
A pathfinder satellite for the TROPICS mission launched last June on a SpaceX rideshare mission has performed well in orbit, collecting test measurements of temperature and moisture over multiple tropical cyclones, including Hurricane Ida before making landfall. came to Louisiana.
The experience with the TROPICS pathfinder satellites inspires confidence that the six operational satellites will work, McCarty said.
“Our requirement from NASA is to collect scientific data for a year, and we hope to go longer than that,” Blackwell said. “There are instances where these CubeSats last three years or even longer, so we hope it will be significantly longer than the one-year requirement.”
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