A Preliminary Search For Planets and Exozodiacal Emission Around Alpha Centauri A with JWST/MIRI

We present F1550C (15.5 μm) coronagraphic imaging observations of the nearest solar-type star α Cen A using the James Webb Space Telescope (JWST) Mid-InfraRed Instrument (MIRI).

The observations, executed in 2025 February, were compromised by having only one successful roll and degraded performance due to a position mismatch (Δr ∼ 10 mas) between α Cen A and the best-matching reference observation behind the MIRI coronagraph.

We set preliminary upper limits on both the presence of a planet and an exozodiacal dust disk. The observations are sensitive to a planet heated by α Cen A (200–250 K) with a radius ≳1 RJup at a separation of 1 5 (2 au) and zodiacal dust emission at the level of ≳5–10 times the brightness of our own zodiacal cloud.

A complete analysis of all JWST/MIRI observations of α Cen A is forthcoming in Paper I (Beichman & Sanghi et al. 2025, in preparation) and Paper II (Sanghi & Beichman et al. 2025, in preparation).

A Preliminary Search for Planets and Exozodiacal Emission Around α Centauri A with JWST/MIRI, Research Notes of the AAS, (open access)

Astrobiology,