[STSCI]. ESA’s Characterising Exoplanet Satellite (CHEOPS) has helped revolutionize our understanding of exoplanet science during its first six years of successful science operations by precisely measuring planet sizes and revealing the compositions, atmospheres, and diversity of planetary systems.
To provide synergy opportunities with other missions, Principal Investigators of active James Webb Space Telescope (JWST) and/or Hubble Space Telescope (HST) General Observer programs are now eligible to request complementary simultaneous CHEOPS observations through the Fast-Track route without submitting a scientific justification.
Fast-Track proposals bypass scientific evaluation by the CHEOPS Time Allocation Committee (TAC). Instead, they undergo a technical feasibility assessment before observing time is granted. This provides an expedited route to obtaining complementary CHEOPS photometry in support of existing HST and JWST programs, subject to the applicable feasibility checks.

As an example of the type of science that this might allow, Figure 1 shows a combined analysis of CHEOPS, TESS, JWST/NIRISS and JWST/NIRSPEC data for the mini-Neptune TOI-1130 b (Barat et al. 2026).
The deadline for each monthly submission cycle is on the last calendar day of the month. Observers with questions about the Fast-Track proposals initiative should contact the CHEOPS team
Astrobiology,
