noun, plural [ ahr-keh-num ]
Secrets or mysteries

Arcanum is a multi-role spacecraft for the outer Solar System consisting of a large Neptunian orbiter and a soft-landing Triton probe. The spacecraft is designed to be at the forefront of next-generation space science missions, showcasing what will be possible with new super heavy-lift launch vehicles such as SpaceX Starship.

Watch the introduction
Somerville Orbiter CAD render


The orbital component Somerville will perform multiple flybys on a 15-year trajectory to Neptune before finally capture burning into a highly-eccentric orbit; providing deep-space observation windows at apogee and planetary science measurements at perigee.

Remote sensing and in-situ measurements ranging from gamma-ray spectrometry to dust detection will allow a comprehensive understanding of the Neptunian environment, and an optical wavelength telescope will allow deep-space observations to be made outside the zodiacal light interference of the inner Solar System.


The Bingham soft-landing probe will detach from Somerville during a Triton flyby, alongside two surface impact penetrators.

Sequenced landings will allow the conduction of a seismic experiment on the interior structure of the moon, and additional instrumentation will allow near-surface atmosphere, surface, and subsurface measurements to be taken.

Bingham Lander CAD render

Arcanum Papers

Arcanum GLEX 2021 paper cover

GLEX 2021

St Petersburg, Russia

June 2021

An L-class Multirole Observatory and Science Platform for Neptune


Arcanum JBIS Vol 74.9 paper cover

JBIS Vol 74.9

British Interplanetary Society

September 2021

Scientific Objectives and Instruments for Neptune, Triton and KBOs

BIS Shop

Arcanum IAC 2021 paper cover

IAC 2021

Dubai, UAE

October 2021

Concept of Operations for a Neptune System Mission