Featured image credit: Rocket Lab
Launch Window | March 16, 2023 – 22:38 UTC | 18:38 EDT |
|---|---|
Mission Name | Stronger Together |
Launch Provider | Rocket Lab |
Customer | Capella Space |
Rocket | Electron |
Launch Location | Launch Complex 2, Wallops Island, Virginia, USA |
Payload mass | ~220 kg (~490 Ib) |
Where is the satellite going? | 600 km LEO at 44° inclination |
Will they be attempting to recover the first stage? | No, Rocket Lab will not attempt to recover the first stage on this launch |
Where will the first stage land? | It will crash into the Atlantic |
Will they be attempting to recover the fairings? | No |
Are these fairings new? | Yes |
How’s the weather looking? | The weather is currently 95% GO for launch (as of March 16, 2023 – 15:05 UTC) |
This will be the: | – 2nd Rocket Lab launch of 2023 – 2nd launch from Launch Complex 2, Wallops Island, Virginia – 34th Electron launch – 38th orbital launch attempt of 2023 |
Where to watch | Official livestream |
What Does All This Mean?
Stronger Together will be Rocket Lab’s 34th launch overall and its 2nd launch this year, as well as its 2nd launch from Launch Complex 2. Their Electron rocket will be launching two satellites for Capella Space into a circular 600 km low Earth orbit. Capella 9 and 10 are Capella Space’s second generation synthetic aperture radar (SAR) Earth observation satellites.
Stronger Together
Stronger Together is a dedicated launch for Capella Space to carry two satellites into a circular 600 km low Earth orbit (LEO) at 44° inclination. The mission will deploy the two 112 kg heavy synthetic aperture radar (SAR) satellites to join the existing fleet of eight Capella satellites. This launch will mark the last launch of Capella Space’s second generation Whitney satellites with Capella 9 and Capella 10.
Capella Space’s satellites are synthetic radar aperture Earth observation satellites utilizing radar and its reflection from the ground to map the Earth’s surface. Using radar has certain advantages over using optical-based methods. Radar, depending on the frequency used, can observe the surface through clouds, haze, and other obstructions that optical based systems struggle with. Synthetic aperture radar can also achieve better spatial resolution compared to similar sized optical ones with 0.5 m per pixel on Capella Space’s second generation satellites.
Second Generation Capella Satellites
After Capella Space launched its first technology demonstrator satellite back in December of 2018 on a SpaceX Falcon 9, they launched another test satellite on Rocket Lab’s Electron on the I Can’t Believe It’s Not Optical mission on August 31, 2020. The first and second satellite were called Denali and Sequoia respectively, with the generation two satellites being called Whitney.
Whitney 1 through Whitney 6 were all launched on SpaceX Falcon 9 rockets as part of either Transporter missions, or as a rideshare on SpaceX’s own Starlink launches. Whitney 7 and Whitney 8, also known as Capella 9 and Capella 10, will both launch on top of Rocket Lab’s Electron rocket.
Capella Space’s Whitney satellites achieve a spatial resolution of 0.5 m per pixel utilizing a 3.5 m deployable mesh-based reflector antenna, which captures and focuses the reflected radar waves. The satellites feature a single polarized X-band instrument that operates between 9.5 and 9.9 GHz.
Third Generation Capella Satellites
Capella space has announced its third generation SAR satellites that will improve upon generation two. These new satellites will be nicknamed Acadia and will get the spatial resolution down to just 0.3 m per pixel. Next to various system upgrades, Acadia satellites will also feature a inter-satellite laser-link terminal by Mynaric that will enable them to use their satellites as relays to provide images of observed areas in under 15 minutes. The used bandwidth will also increase from 500 MHz to 700 MHz. Out of the five scheduled launches with Rocket Lab in 2023, four of them will carry these next generation satellites.
Capella Satellite Overview
| Capella 1 | Capella 2 | Capella 3-4 | Capella 5 | Capella 6 | Capella 7-8 | Capella 9-10 | Capella 11+ | |
|---|---|---|---|---|---|---|---|---|
| Name | Denali | Sequoia | Whitney 1-2 | Whitney 3 | Whitney 4 | Whitney 5-6 | Whitney 7-8 | Acadia |
| Generation | Gen 1 (Technology Demonstrator) | Gen 1.5 | Gen 2 | Gen 2 | Gen 2 | Gen 2 | Gen 2 | Gen 3 |
| Inclination | 97.7° | 45.1° | 97.5° | 97.5° | 53° | 97.5 | 44° | TBD |
| Launch Date | Dec 03, 2018 | Aug 31, 2020 | Jan 24, 2021 | June 30, 2021 | May 15, 2021 | Jan 13, 2022 | Mar 16, 2023 | NET 2023 |
| Launch Vehicle | Falcon 9 Block 5 | Electron Photon | Falcon 9 Block 5 | Falcon 9 Block 5 | Falcon 9 Block 5 | Falcon 9 Block 5 | Electron Photon | TBD |
| Status | Operational | Operational | Operational | Operational | Operational | Operational | Operational | Operational |
Timeline
Pre-Launch
| Hrs:Min:Sec From Lift-Off | Events |
| – 05:00:00 | Electron is Raised Vertical, Fueling Begins |
| – 03:00:00 | Launch Pad is Cleared |
| – 02:30:00 | LOx Load Begins |
| – 00:12:00 | GO/NO GO poll |
| – 00:02:00 | Launch auto sequence begins |
Launch
| Hrs:Min:Sec From Lift-Off | Events |
| – 00:00:02 | Rutherford Engine Ignition |
| 00:00:00 | Lift-Off |
| + 00:01:00 | Vehicle Supersonic |
| + 00:02:25 | Main Engine Cut-Off (MECO) on Electron’s first stage |
| + 00:02:28 | Stage 1 Separation |
| + 00:02:31 | Stage 2 Rutherford Engine Ignition |
| + 00:03:09 | Fairing Separation |
| + 00:06:16 | Battery hot-swap |
| + 00:09:10 | Second Engine Cut-Off (SECO) on Electron’s Second Stage |
| + 00:09:14 | Stage 2 Separation from Kick Stage |
| + 00:53:52 | Kick Stage Curie Engine Ignition |
| + 00:57:28 | Curie Engine Cut-Off |
| ~+ 00:57:28 | Payload Deployed |
What Is Electron?
Rocket Lab’s Electron is a small-lift launch vehicle designed and developed specifically to place small satellites (CubeSats, nano-, micro-, and mini-satellites) into LEO and Sun-synchronous orbits (SSO). Electron consists of two stages with optional third stages.
Electron is about 18.5 meters (60.7 feet) in height and only 1.2 meters (3.9 feet) in diameter. It is not only small in size, but also light-weight. The vehicle structures are made of advanced carbon fiber composites, which yields an enhanced performance of the rocket. Electron’s payload lift capacity to LEO is 300 kg (~660 lbs).
The maiden flight It’s A Test was launched on May 25, 2017, from Rocket Lab’s Launch Complex-1 (LC-1) in New Zealand. On this mission, a failure in the ground communication system occurred, which resulted in the loss of telemetry. Even though the company had to manually terminate the flight, there was no larger issue with the vehicle itself. Since then, Electron has flown a total of 33 times (30 of them were fully successful) and delivered 155 satellites into orbit.
First And Second Stage
| First Stage | Second Stage | |
|---|---|---|
| Engine | 9 Rutherford engines | 1 vacuum optimized Rutherford engine |
| Thrust Per Engine | 24 kN (5,600 lbf) | 25.8 kN (5,800 lbf) |
| Specific Impulse (ISP) | 311 s | 343 s |
Electron’s first stage is composed of linerless common bulkhead tanks for propellant, and an interstage, and powered by nine sea-level Rutherford engines. The second stage also consists of tanks for propellant (~2,000 kg of propellant) and is powered by a single vacuum optimized Rutherford engine. The main difference between these two variations of the Rutherford engine is that the latter has an expanded nozzle that results in improved performance in near-vacuum conditions.
For the Love At First Insight mission, the company introduced an update to the second stage by stretching it by 0.5 m. Moreover, they flew an Autonomous Flight Termination System (AFTS) for the first time.
Rutherford Engine
Rutherford engines are the main propulsion source for Electron and were designed in-house, specifically for this vehicle. They are running on rocket-grade kerosene (RP-1) and liquid oxygen (LOx). There are at least two things about the Rutherford engine that make it stand out.
Firstly, all primary components of Rutherford engines are 3D printed. Main propellant valves, injector pumps, and engine chamber are all produced by electron beam melting (EBM), which is one of the variations of 3D printing. This manufacturing method is cost-effective and time-efficient, as it allows to fabricate a full engine in only 24 hours.
Rutherford is the first RP-1/LOx engine that uses electric motors and high-performance lithium polymer batteries to power its propellant pumps. These pumps are crucial components of the engine as they feed the propellants into the combustion chamber, where they ignite and produce thrust. However, the process of transporting liquid fuel and oxidizer into the chamber is not trivial. In a typical gas generator cycle engine, it requires additional fuel and complex turbo-machinery just to drive those pumps. Rocket Lab decided to use battery technology instead, which allowed eliminating a lot of extra hardware without compromising the performance.
Different Third Stages
Kick Stage
Electron has optional third stages, also known as the Kick Stage, Photon, and deep-space version of Photon. The Kick Stage is powered by a single Curie engine that can produce 120 N of thrust. Like Rutherford, it was designed in-house and is fabricated by 3D printing. Apart from the engine, the Kick Stage consists of carbon composite tanks for propellant storage and 6 reaction control thrusters.
The Kick Stage in its standard configuration serves as in-space propulsion to deploy Rocket Lab’s customers’ payloads to their designated orbits. It has re-light capability, which means that the engine can re-ignite several times to send multiple payloads into different individual orbits. A recent example includes Electron 19th mission, They Go Up So Fast, launched in in 2021. The Curie engine was ignited to circularize the orbit, before deploying a payload to 550 km. Curie then re-lighted to lower the altitude to 450 km, and the remaining payloads were successfully deployed.
Photon And Deep-space Photon
Rocket Lab offers an advanced configuration of the Kick Stage, its Photon satellite bus. Photon can accommodate various payloads and function as a separate operational spacecraft supporting long-term missions. Among the features that it can provide to satellites are power, avionics, propulsion, and communications.
But there is more to it. Photon also comes as a deep-space version that will carry interplanetary missions. It is powered by a HyperCurie engine, an evolution of the Curie engine. The HyperCurie engine is electric pump-fed, so it can use solar cells to charge up the batteries in between burns. It has an extended nozzle to be more efficient than the standard Curie, and runs on some “green hypergolic fuel” that Rocket Lab has not yet disclosed.
