WASHINGTON — A Rocket Lab Electron launched a pair of NASA cubesats designed to watch the event of tropical storms, 11 months after the primary satellites within the constellation were lost when a unique rocket failed.
The Electron lifted off from the corporate’s Launch Complex 1 in Latest Zealand at 9 p.m. Eastern May 7. The rocket’s kick stage deployed the 2 Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) cubesats about 35 minutes after liftoff, although that was not confirmed until a ground station pass 20 minutes later.
The Electron placed the 3U cubesats right into a 550-kilometer orbit at an inclination of 32 degrees. The kick stage, normally used on Electron launches to circularize the orbit, performed the inclination change needed for the payloads.
A second Electron will launch two more TROPICS cubesats about two weeks later. The four-satellite system will give you the chance to watch tropical storm development using a microwave radiometer on each satellite that may collect temperature and water vapor profiles. With 4 satellites, TROPICS will give you the chance to get hourly updates that may aid in monitoring the formation of hurricanes and other tropical weather systems.
“We’ll be getting data we’ve never had before, which is that this ability to look within the microwave wavelength region within the storms with hourly cadence to have a look at the storm because it forms and intensifies,” said William Blackwell, TROPICS principal investigator on the MIT Lincoln Laboratory, during an April 28 media call. “We hope to enhance our understanding of the essential processes that drive the storms and ultimately improve our ability to forecast the track and intensity.”
TROPICS was originally a six-satellite constellation. The primary two satellites were launched on an Astra Rocket 3.3 in June 2022 as a part of a three-launch contract valued at nearly $8 million, but failed to achieve orbit when the rocket’s upper stage ran out of kerosene fuel and shut down prematurely.
Astra subsequently retired the Rocket 3.3, forcing NASA to search out a brand new option to launch the remaining 4 satellites. The agency chosen Rocket Lab in November 2022 to launch them on two dedicated Electron launches from the corporate’s recent Launch Complex 2 on Wallops Island, Virginia. NASA made the award under its Enterprise-class Acquisition of Dedicated and Rideshare (VADR) contract, issuing Rocket Lab a task order valued at $12.99 million.
Rocket Lab said April 10 that it will move the 2 TROPICS launches from Virginia to Latest Zealand. “The timeline wherein we could get the spacecraft launched out of Virginia didn’t correlate with the timeline that was required to get these spacecraft in orbit for the storm season,” Peter Beck, chief executive of Rocket Lab, said within the media call. He didn’t elaborate on the problems that kept the launches from happening on schedule from Virginia.
NASA officials said they were tremendous with the change in launch sites. “We’re largely launch site agnostic,” said Bradley Smith, director of launch services in NASA’s Space Operations Mission Directorate. “So long as the launch provider can meet the mission requirements, it’s their alternative where they need to go.”
Beck said the change in launch sites got here at no additional cost to NASA. Ben Kim, program executive in NASA’s Earth science division, said there was some extra logistics and paperwork to get the TROPICS satellites to Latest Zealand, but that they were minor. The TROPICS mission manager on the launch site “might be having the worst time because I keep calling and messaging him in the course of the night, forgetting in regards to the time difference.”
Provided the second launch is successful, NASA expects to have the four-satellite system in operation by the beginning of the Atlantic hurricane season this summer. Having 4 as an alternative of the originally planned six “does make a difference,” Blackwell said, with revisit times 10 to quarter-hour longer than if there have been six. “We’re still higher than our requirement of 60 minutes with only 4 satellites.”