CubeSpec

The mission

CubeSpec is a 12U CubeSat mission which will focus on asteroseismology of bright pulsating stars (VIS mag. 4) with observations of 15 minutes every orbit per star for 1-3 months.

Platform: 12U CubeSat with arcsecond 3-axis pointing.
Payloads: High resolving power (50,000) UV/VIS spectrometer configurable for different science cases, athermal opto-mechanical design, Fine Guidance Sensor with piezo-electric tip-tilt mirror in the ADCS control loop.
Programme: General Support Technology Programme (GSTP).
Consortia: KU Leuven, Amos, Arcsec (BE).

Mission description

A variety of astrophysical questions requires uninterrupted spectral monitoring of stars from space over weeks or months. Spectroscopy from space is currently only feasible on large platforms, not affordable to dedicate long term monitoring of individual sources. The goal of the CubeSpec project is to develop and demonstrate a 12U CubeSat solution to deliver stellar spectroscopy from space. The final objective of the project is to offer the astronomical community a standard spectroscopy CubeSat solution to go from science case to first in-orbit observation in short time at low cost. Adaptation to the specific observation needs are possible with minimal hardware changes to select wavelength coverage (between 200-1000 nm) and resolution (R=50-50000) required to address specific science cases. 

A small space platform providing spectroscopic observing capability of stars can help solve a variety of astrophysical questions, among which: 

• Unravelling the internal structure of massive stars from variations in the line profiles in their spectrum.  
• Spectroscopic surveys in wavelength regions severely contaminated by telluric lines from the Earth's atmosphere. 
• Transit spectroscopy of exoplanets. 
• Characterisation of host stars of exoplanets.

For the IOD mission, one specific and potentially high-impact primary science case has been chosen: unravelling the interior of massive stars. By conducting repeated measurements of specific stars for 15 minutes every orbit over a minimum period of three months at such high resolving power, the acquired line spectra time-series can be processed on the ground to reveal interior seismic activity. Therefore, CubeSpec will be the world's first CubeSat to demonstrate high-resolution stellar spectroscopy, and will enable a unique cost-effective and highly responsive future capability for the astronomical community. 

The key miniaturised technologies to be demonstrated on the mission are: 

• Compact science-grade high resolution spectrometer (telescope & instrument incl. optical bench & detector).
• Line-of-sight stabilisation incl. fine steering mirror & fine guidance sensor integrated with the instrument & ADCS providing arcsecond-level pointing accuracy over payload integration times of up to 15 minutes. 
• Structure and thermal design providing high thermo-elastic stability for the payload.
• Deployable elements providing straylight protection to the payload from the Sun and Earth albedo.

Mission status

Launch: Q2 2026 to SSO 500 km dawn-dusk.
Status: Phase C-F contract kicked-off, Phase C ongoing, CDR planned in May 2025.