EQUULEUS Spacecraft

Lunar L2 (libration-point) orbiter to demonstrate technologies and characterize environment.

Lunar L2 (libration-point) orbiter. Demonstrate trajectory design and control techniques and the associated technologies in the Sun-Earth-Moon perturbed region by a nano-spacecraft; To study the radiation environment in the geospace; To characterize the flux of impacting meteors at the far side of the Moon. Water propulsion system. The scientific payload consists of PHOENIX, an extreme ultra violet imager to observe the Earth plasmasphere; DELPHINUS, a camera to detect lunar impacts on the dark side of the Moon; and CLOTH, a thin-film within the CubeSat's MLI (Multi-Layer Insulation) to detect small objects in the cis-lunar space.

ArkEdge Space was commissioned by the University of Tokyo, to participate in the initial operations of EQUULEUS in space, and contributed greatly to the completion of the initial operations and the transition to regular operations.

EQUULEUS, a Nano-Explorer Heading for the Moon, Successfully Maneuvers Beyond Low Earth Orbit for the First Time in the World With a Water Thruster on Board.

PHOENIX: Plasmasphere Telescope
After launch, the initial checkout (health check, shutter operation, HV operation, etc.) of PHOENIX has started in December 2022, and in-flight calibration is underway based on the observation results of the white dwarf HZ43 and the moon obtained in April 2023.

CLOTH: Dust Detector
Since the initial check-out operation was successfully conducted on November 25, 2022, CLOTH has achieved 2473 hours of cumulative observation time (waiting time for dust detection) and recorded more than 0.5 million events including a huge amount of noise events. We identified some candidates for dust impact events from the ongoing data screening process, carefully comparing the ground calibration results. One of the candidates shows similar signal features such as pulse amplitude, width, and number to those obtained with a 20-micron particle impacted at 6 km/s.

DELPHINUS: Lunar Impact Flash Telescope
When a meteoroid with a diameter of several centimeters to several tens of centimeters impacts the lunar surface, a Lunar Impact Flash, here after "LIF", is produced in the visible to near-infrared wavelength range which can be observed by ground-based telescopes as a magnitude 5 to 11 with short duration, 0.01 to 0.1 seconds, flash. Some first light images observed by DELPHINUS are shown.

After completing its major orbital maneuvers and achieving full mission success, communication with EQUULEUS was lost in 18th May 2023. Rapid fault tree analysis and optical observations using large telescopes indicated the spacecraft was likely in an uncontrolled tumbling state. Recovery operations were planned to re-establish communication by identifying potential times for sufficient solar power generation

One of 13 SLS 6U Interplanetary or Lunar CubeSats. IAC 2016.

• ADCS - Blue Canyon XACT-50
• THRUSTER - Pale Blue

[1] [2] [3]

• ArgoMoon
• BioSentinel
• CuSP
• EQUULEUS
• LunaH-Map
• Lunar IceCube
• LunIR
• Miles
• NEA-Scout
• OMOTENASHI