Just below three weeks after Rocket Lab launched the “Rocket Like a Hurricane” mission placing two time-resolved observations of precipitation structure and storm intensity with a constellation of smallsats (TROPICS) satellites for NASA into low Earth orbit, the corporate is about to launch its Electron rocket on the “Coming to a Storm Near You” mission. Launching from Launch Complex 1B (LC-1B) on the Mahia Peninsula in Latest Zealand, this mission will place the ultimate batch of TROPICS satellites into orbit.
Thursday’s attempt was called off attributable to unacceptable weather, moving the launch to May 27 in a window that opens 03:30 UTC (15:30 local time).
NASA’s TROPICS constellation is made up of 5 3U cubesats, each measuring 10 x 10 x 36 centimeters and mass just over five kilograms.
The TROPICS satellites orbit in two equally spaced orbital planes and can find a way to supply hourly measurements on cyclone activity within the Atlantic and West Pacific regions and can help improve our understanding of how these storms evolve over time in addition to improve intensity and direction forecasts for cyclones.
To perform this, each satellite is supplied with a 12-channel passive microwave spectrometer that may measure temperature, humidity, precipitation, and cloud properties.
The constellation was originally speculated to be made up of 12 satellites but was later reduced to only seven with the primary launch being a pathfinder spacecraft aboard SpaceX’s Transporter-2 mission in June 2021.
**INSERT LIVESTREAM LINK HERE**
After the launch of the pathfinder satellite, the primary two operational satellites were launched aboard Astra’s LV0010 mission on June 12, 2022, where the corporate’s Rocket 3.3 was tasked with placing the 2 cubesats right into a planned circular orbit of 550 km. Nevertheless, a difficulty with the vehicle’s upper stage led to an early shutdown of its Aether engine, making the launch vehicle unable to succeed in orbit and the 2 satellites subsequently burned up upon reentry into the Earth’s atmosphere a short while later.
Shortly after the failure, Astra announced the retirement of the Rocket 3.3 system in favor of its more powerful Rocket 4 launch vehicle currently in development. In late September, NASA decided to maneuver the remaining two TROPICS launches off of Rocket 3.3 and started looking for a brand new launch provider. On Nov. 23, NASA announced that the agency had chosen Rocket Lab to launch the remaining 4 cubesats over the course of two launches utilizing the corporate’s Electron rocket.
The remaining 4 cubesats should be launched inside a 60-day window of one another; attributable to this, Rocket Lab will conduct each TROPICS launches back to back. The primary batch successfully launched on May 8 on the mission dubbed “Rocket Like a Hurricane.”
Monday’s mission, “Coming to a Storm Near You,” will see Electron lift off from Rocket Lab’s LC-1B in Mahia, Latest Zealand. This will probably be Rocket Lab’s fifth mission of 2023 and thirty seventh overall for the corporate.
Electron is a two-stage liquid-fueled small satellite launch vehicle that’s designed and manufactured in-house by Rocket Lab. Each of Electron’s stages run off rocket propellant 1 (RP-1) Kerosene and liquid oxygen (LOX) and the first structure is made up of carbon fiber composite.
The primary stage sports nine Rutherford engines, which were the primary electric pump-fed cycle engines used on an orbital launch vehicle. Each engine produces roughly 25 kN (~5,600 lb) of thrust at sea level and increases to 26 kN (~5,800 lb) within the vacuum of space.
The second stage is powered by a single vacuum-optimized Rutherford also producing 26 kN (~5,800 lb) of thrust.
For this mission, Electron will utilize its kick stage. Powered by the corporate’s Curie engine, the kick stage is situated contained in the vehicle’s two fairing halves and allows precise deployment of payloads into a particular orbit.
During Monday’s launch, after being fully fueled with RP-1 and nearly fully loaded with LOX, Electron’s launch auto sequence will begin at T-2 minutes. Right now, the vehicle will go on internal power and the automated flight termination system (AFTS) will probably be enabled. The AFTS is used to destroy the vehicle within the event of an off-nominal situation in the course of the flight.
Shortly after the vehicle switches to internal power, LOX loading will conclude, completing propellant loading on the vehicle ahead of launch.
At T-2 seconds, Electrons nine Rutherford engines on the primary stage will ignite and the vehicle will lift off the pad a few seconds later.
After clearing the tower, the rocket will begin to pitch over and begin its gravity turn to the northeast to place the vehicle on the correct trajectory to position the satellites into the specified 32-degree inclined orbit.
Electron is anticipated to go supersonic one minute after liftoff and reach max-q, the period where the vehicle experience essentially the most amount of atmospheric stress, around one minute and 11 seconds after launch.
The nine Rutherford engines on the primary stage are expected to burn until across the T+2 minute and 29-second mark, at which point all of the engines will shut down and stages one and two will separate 4 seconds later. The second stage will ignite its vacuum-optimized Rutherford just a few seconds later.
Fairing separation will occur just over three minutes after liftoff and can expose the 2 TROPICS satellites to the vacuum of space for the primary time.
Electron will then perform a battery hot-swap around T+6:52 when the second stage will jettison two of its batteries used to spin the pumps on the engine and swap over to a different charged battery pair. Doing this enables the vehicle to discard unnecessary mass that would cut back performance if it was to stay attached to the second stage.
Stage two will shut down around nine and a half minutes after launch with the kick stage separating just a few seconds later. At this point, the vehicle and payloads will probably be in an initial parking orbit and can coast for ~21.5 minutes as much as the very best point in its orbit, also often known as apogee.
Once at apogee, the Curie engine will ignite on the kick stage for an approximate two-minute and forty-second burn to bring the vehicle right into a circular orbit of 550 km.
Shortly after Curie engine cutoff, the 2 TROPICS satellites will deploy from the payload plate onboard the kick stage.
After deployment, each cubesats will deploy their solar arrays and undergo initial checkouts before starting their jobs as a part of the constellation. With this launch, the TROPICS constellation will probably be officially complete and able to support data gathering on cyclones within the Atlantic and West Pacific regions.