Visibility V / V
C / 2021 A1 (Leonard) The comet was filmed on the second night of the December campaigns. The comet was discovered by American astronomer / geologist Greg J Leonard on January 3, 2021 at Mount Lemmon Observatory. The comet was discovered about 5au away and is in its perihelion on January 3, 2022 from the sun 0.6151au. Greg Leonard has also found comets (10) C / 2017 W2 Leonard, P / 2017 Y3 Leonard, P / 2018 L5 Leonard, P / 2018 VN2 Leonard, 396P / Leonard, C / 2020 H4 Leonard, C / 2020 K3 Leonard, P / 2020 S6 Leonard, C / 2020 X4 Leonard and C / 2021 A1 Leonard and 11 asteroids. Source Wikipedia https://it.wikipedia.org/wiki/Gregory_J._Leonard. As we photographed, the comet was 0.38494au away and the nearest 12 December was 0.23336au.
1Picture The sum of the stack by comet. Coma measured medium stretch 2 '(122 ").
2Picture Same stack MaximDL Histogram Specification Gaussian stretch. The tail extends beyond the field of view, with the tail 40 '(2336 ").
3Picture sum view according to the stars L120s 1-11 image stack, motion is displayed. No asteroids less than 24.0 mag in the picture.
4Picture. first image in the series1 L120s measured, 2021-12-05UT 01: 05: 57UT 2459553.54579JDUT 14h05m55.07s + 26d00'36.6 "N10.06mag Std Dev 2357.712 SNR162.955 FWHM18.229", JPL Horizon 01: 05: 57UT 14h05m54.78s + 26d00'34.2 "T9.5m.
5Picture. last image in the series11 L120s measured, 2021-12-05UT 01: 26: 50UT 2459553.56030JDUT 14h06m07.72s + 26d59'16.4 "N10.124mag Std Dev 2488.544 SNR136.055 FWHM16.415", JPL Horizon 01: 26: 50UT 14h06m07.3s + 26d59'17.1 "T9.5mag.
TYC 2009-16-1 v.11.99mag stars used to calibrate brightness measurement.