Photon is a satellite bus based on

Rocket Lab Rocket Lab Corporation is a Public company, publicly traded aerospace manufacturer and List of launch service providers, launch service provider. Its Rocket Lab Electron, Electron orbital rocket launches Small satellite, small satellites, and ha ...

Electron The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up qua ...

kick stage. It moves satellites into their appropriate orbits once boosted by rockets such as Electron. It is customizable for uses including LEO payload hosting, lunar flybys, and interplanetary missions. Electron small launch vehicle of the Rocket Lab Mission to Venus

Electron small launch vehicle of the Rocket Lab Mission to Venus

Photon uses chemical propulsion for orbit adjustments. It can use a variety of engines, such as the Curie and HyperCurie engines, as well as engines from third-party sources, such as the one powering the EscaPADE mission.73 International Astronautical Congress (IAC) (18 September 20022), ESCAPADE
A Low-Cost Formation at Mars
Retrieved 21 October 2023 Photon first launched in August 2020 on Rocket Lab's ''I Can't Believe It's Not Optical'' mission, where it served as a pathfinder. It has since flown three times. It flew the CAPSTONE mission. Photon communicates on the

S-band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the convention ...

. Depending on the orbital inclination (37° to

Sun-synchronous orbit A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is ...

), it is expected to have a payload capacity of . The interplanetary version was to have a payload capacity. HyperCurie is an evolution of the Curie engine, which comes in

monopropellant Monopropellants are propellants consisting of chemicals that release energy through exothermic chemical decomposition. The molecular bond energy of the monopropellant is released usually through use of a catalyst. This can be contrasted with biprop ...

and bipropellant versions, while the HyperCurie is hypergolic and electrically pumped.

Development

In April 2019,

announced plans to create a new satellite bus, named Photon, to position small satellites into orbit. Its goal was to reduce complexity and development time, enabling technology demonstrations without developing a full spacecraft. The company aimed to broaden its portfolio and diversify its revenue streams. The company announced it was targeting

lunar orbit In astronomy and spaceflight, a lunar orbit (also known as a selenocentric orbit) is an orbit by an object around Earth's Moon. In general these orbits are not circular. When farthest from the Moon (at apoapsis) a spacecraft is said to be at apo ...

as part of its services, enabled by a bi-propellant propulsion system. The development of Photon included working with potential customers, with significant interest from government agencies. The first few Photon satellites would be technology demonstrators before transitioning to operational launches for customers, which started with NASA's CAPSTONE cubesat in June 2022. Rocket Lab planned to launch Photon to Venus in December 2025, delivering a laser-tunable mass spectrometer to the Venusian atmosphere.

Design

Photon is manufactured at Rocket Lab's factory in

Huntington Beach, California Huntington Beach is a seaside city in Orange County, California, United States. The city was originally called Pacific City, but it was changed in 1903 to be named after American businessman Henry E. Huntington. The population was 198,711 as of ...

. It can utilize a variety of engines, including those developed by Rocket Lab itself, such as the Curie and HyperCurie engines, as well as engines from third-party sources, such as the one powering the EscaPADE mission. Photon communicates on

. Depending on the orbital inclination (37° to

), it is expected to have a maximum payload capacity of . The

low Earth orbit A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial object ...

version of Photon can take to

. A modified version of Photon has bigger propellant tanks and the HyperCurie engine for interplanetary missions. The interplanetary version has a payload capacity. HyperCurie is an evolution of the Curie engine, which comes in a

version and a bipropellant version, while the HyperCurie is a hypergolic version. HyperCurie is electrically pumped.

Initial launches

The inaugural Photon satellite was the Photon Pathfinder/First Light satellite ( COSPAR ID 2020-060A) described by Rocket Lab as its "first in-house designed and built Photon demonstration satellite". It was launched aboard Electron rocket on 31 August 2020 on the 14th Electron mission "I Can't Believe It's Not Optical". First Light had a dual role in the mission: first as the final rocket stage delivering the customer satellite (Capella 2) and then as a standalone satellite undertaking its own orbital mission. The purpose of the First Light standalone mission was to demonstrate the new (as compared to "plain" kick stage) systems for operating in orbit as a long-duration standalone satellite. To demonstrate Photon's payload hosting capabilities, First Light had a low-resolution video camera. The second formal test, Photon Pathstone, was launched on 22 March 2021 on the 19th Electron mission "They Go Up So Fast". Like First Light, Pathstone first delivered customer satellites to orbit before transitioning into its own satellite operations. Pathstone operations were aimed at building flight heritage and focused on testing systems in preparation for launching NASA's CAPSTONE smallsat mission in June 2022. These tests included power and thermal management, attitude control via reaction wheels and communications systems. The first operational launch for Photon was NASA's CAPSTONE smallsat mission. Qualification of the Photon kick stage for this mission was underway by December 2020. Photon delivered CAPSTONE on a

trans-lunar injection A trans-lunar injection (TLI) is a propulsive maneuver, which is used to send a spacecraft to the Moon. Typical lunar transfer trajectories approximate Hohmann transfers, although low-energy transfers have also been used in some cases, as with ...

(TLI) burn on 6th day from liftoff after performing 6 apogee raising burns at perigee within every 24 hours from liftoff, leading to TLI and a near-rectilinear halo orbit. After this the CAPSTONE was deployed in its journey to the Moon. After completing all the mission requirements for NASA, Rocket Lab utilised its Photon spacecraft for a low-altitude lunar flyby.

Photon versions

Due to the high amount of customization Photon can undergo, Rocket Lab decided to rebrand Photon and split it into different spacecraft: Explorer, Lightning, Pioneer, and Photon.

Explorer

Explorer is a high delta-V spacecraft designed for deep space missions. The first Explorer flew in 2022 and delivered CAPSTONE to a trajectory towards the Moon. Currently, two Explorers are being built for the EscaPADE mission. Explorer can be launched on any rocket, depending on the mission profile.

Lightning

Lightning is designed for LEO constellations and is intended to operate for 12+ years in LEO. It boasts a 3 kW power delivery system and is suited for high-duty-cycle telecommunications and remote sensing. Lightning currently has no flight heritage, with the first launch planned for 2025. Both the satellites (buses) for Globalstar and the

Space Development Agency The Space Development Agency (SDA) is a United States Space Force direct-reporting unit tasked with deploying disruptive space technology.SDA.miAbout Us One of the technologies being worked on is space-based missile tracking using large global s ...

are based on the Lightning architecture.

Pioneer

Pioneer is a highly specialized satellite bus designed to support payloads up to 120 kg for special missions, including re-entry and dynamic space operations. Pioneer first took flight in 2023, supporting a mission for Varda Space Industries where the capsule atop the bus grew crystals of the drug ritonavir. After growing the crystals and experiencing some regulatory hold-ups, the spacecraft returned to Earth and landed in Utah.

Photon

Photon is the upgraded version of Rocket Lab's kick stage. It features power, propulsion, and communications systems for delivering payloads to LEO. The first Photon was launched in 2020, deploying a satellite for Capella Space. After deployment, the Photon spacecraft served as a pathfinder.

Operational statistics

Mission outcomes

Variations

Mission history

Upcoming missions

Confirmed upcoming missions for Photon and Photon variants.

References

{{Rocket Lab

Photon A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless particles that can ...

Satellite buses