[4] SPECULOOS-3 b takes only about 17 hours to complete an orbit around SPECULOOS-3, and, because of that proximity, it receives very high levels of radiation and is tidally locked, meaning that one side of the planet always faces its host star.

[1] As a consequence, the planet receives high levels of radiation from its host star,[5] and its planetary equilibrium temperature is estimated at 280°C assuming a null bond albedo, meaning that its dayside is likely made of solid rock.

[4][5][6] Due to the planet's high temperature and its host star's infrared brightness, its dayside's astronomic spectrum (of emission) might be measured by the MIRI/RLS instrument aboard the James Webb Space Telescope.

[2] The host star SPECULOOS-3 was observed by the SAINT-EX telescope in 2021, for five nights, producing two light curves containing planetary transits.

The star was later reviewed by the SPECULOOS-North observatory's Artemis telescope, revealing a clear transit-like signature on its light curve.