Coin-sized camera spots distant planets ⚡ экспресс
Using the telescopic navigation camera ONC-T (effective aperture 15 mm) aboard the Hayabusa2 spacecraft, transit observations of the hot Jupiters WASP-189 b and MASCARA-1 b were performed: 10 and 4 events, respectively. The signal-to-noise ratio for a single transit was 13 and 8, and after stacking all events, it reached 40 and 16. The mid-transit time was measured with an accuracy of 6 minutes and agrees with TESS data within 2 minutes; the planet-to-star radius ratio was determined with an absolute uncertainty of 0.004 (6%), and the deviation from TESS is no more than 0.002 (3%). Joint analysis allowed refinement of the ephemerides and revealed a 4σ discrepancy for the orbital period of MASCARA-1 b. ONC-T set a record as the instrument with the smallest aperture to detect an exoplanet transit from space; the results point to the potential for detecting long-period Jupiters with miniature optics — a population poorly represented in current surveys.
The camera lens is no bigger than a quarter. You'd find it in a smartphone, but here it was mounted on the Hayabusa2 probe for asteroid landings. Yet scientists asked it to gaze afar—and the little thing pulled off the transit method (watching a planet cross its star's disk and slightly dim its light) for the first time, spotting exoplanets—worlds around other suns.
The camera caught the shadows of two scorching gas giants. Their passages caused brightness dips of mere fractions of a percent—like a chandelier's glow momentarily flickering as a mosquito flits by. By repeatedly capturing eclipses, astronomers stacked the signals and performed precise photometry (light measurement). One planet's orbital period had to be corrected—the discrepancy with earlier data was too large to ignore.
This success proves you don't need giants to hunt for worlds. Sometimes a baby camera is enough. The real twist? The instrument was built for navigation during landing on asteroid Ryugu, not astronomy. Now miniature tools can blaze a trail to finding long-period planets that big surveys miss.
🎯 The ONC-T camera was originally built for navigation during landing on asteroid Ryugu—now it's snagged an astronomical record.