ARRAKIHS

ARRAKIHS
Mission typeCosmology, Dark Matter
OperatorESA
Websitehttps://www.arrakihs-mission.eu/
Mission duration3 years (nominal)
Spacecraft properties
ManufacturerSatlantis (Instrument) AVS and Redwire (platform primes to PDR)
Landing mass600 kg
Payload mass160 kg
Dimensions~1.5 x 1.5 x 1.6 m3
Start of mission
Launch dateExpected 2030
Main telescope
Type2 x iSIM170 camera
Focal length1500 mm (f/10.15)
Wavelengths280-900 nm visible 900-1600 nm near infrared

ARRAKIHS (Analysis of Resolved Remnants of Accreted galaxies as a Key Instrument for Halo Surveys) is a planned European Space Agency (ESA) space mission designed to study dark matter and galaxy formation by observing low-surface-brightness structures in the halos of nearby galaxies. Selected in November 2022 as an ESA F-class mission, ARRAKIHS is currently in its definition phase, with a projected launch in 2030.

The mission aims to test the Λ-Cold Dark Matter (ΛCDM) model by analysing discrepancies between theoretical predictions and observations of small-scale structures, such as tidal stellar streams and dwarf satellite galaxies. To achieve this, ARRAKIHS will observe the local universe at very low surface brightness levels never before reached in visible and infrared wavelengths, using an innovative binocular telescope system designed specifically to capture ultra-low surface brightness images. The instrument will be launched on a mini-satellite that will orbit the Earth at an altitude of 800 km.