TRAPPIST C/2021 A1 (Leonard) comet production rates

E. Jehin, Y. Moulane, and J. Manfroid, report that they obtained on 19 December, from 00:15 to 01:15 UT, with the TRAPPIST-South (code=I40) robotic telescope (Jehin el al. 2011) located at the ESO La Silla Observatory (Chile), three sets of cometary HB narrowband filters (Farnham et al. 2000) and broad band filters (B,V,Rc,Ic) on comet C/2021 A1 (Leonard) at high airmass under photometric conditions

Large outburst of comet 73P/Schwassmann-Wachmann 3

We report about a large outburst of the Jupiter family-comet 73P/SW-3 that happened between September 30 and October 5 UT 2022, about 40 days after its perihelion

TRAPPIST comets production rates: C/2017 K2 (PanSTARRS), C/2022 E3 (ZTF), C/2022 P1 (NEOWISE), and 73P/SW-3

The authors report that they obtained from TRAPPIST robotic telescopes (Jehin et al. 2011) recent observations using cometary HB narrowband filters (Farnham et al. 2000) for the following comets and computed preliminary production rates at 10.000 km using a Haser Model (Vp=Vd=1km/s) (Haser 1957)

TRAPPIST comets production rates: C/2017 K2 (PanSTARR), C/2022 E3 (ZTF), C/2022 P1 (NEOWISE), and 73P/SW-3

The authors report that they obtained from TRAPPIST robotic telescopes (Jehin et al. 2011) recent observations using cometary HB narrowband filters (Farnham et al. 2000) for the following comets and computed preliminary production rates at 10.000 km using a Haser Model (Vp=Vd=1km/s) (Haser 1957)

TRAPPIST comet production rates: C/2017 K2 (PanSTARR), C/2021 E3 (ZTF), and 22P/Kopff

The authors report that they obtained from TRAPPIST-South (code=I40, la Silla Chile) robotic telescope (Jehin el al. 2011) recent observations using cometary HB narrowband filters (Farnham et al. 2000) for the following comets and computed preliminary production rates at 10.000 km using a Haser Model (Vp=Vd=1km/s) (Haser 1957)

Monitoring the activity and composition of comet C/2017K2 (PanSTARRS) with TRAPPIST telescopes

We report on the results of a long photometry and monitoring of comet C/2017 K2 (PanSTARRS), hereafter 17K2, with the TRAPPIST telescopes [1]. 17K2 is an Oort cloud comet discovered by the Pan-STARRS survey in 2017 [2], at a large heliocentric distance of 16 au. The comet was later identified in archival imagery to be active at 23.8 au from the Sun, the second most distant discovery of an active comet [3]. It has been claimed that 17K2 is a rare CO-rich comet [4]. We started observing 17K2 with TRAPPIST-North on October 25, 2017 using broad-band filters when the comet was at 15 au from the Sun with a magnitude of 18. We started collecting broad and narrow-band images [5] with TRAPPIST-South on September 9, 2021 (rh=5.4 au) when the comet became visible and bright from the southern hemisphere. The comet will reach its perihelion on December 19, 2022 at rh=1.8 au, and we will monitor its activity on both sides of perihelion. As writing this abstract, we detected emission of CN, C2, and C3 radicals as well as the dust continuum in four bands. By fitting the observed gas profiles with Haser model [6] after subtraction of the dust continuum, we derived the gas production rates for a different detected species. From the continuum and broad-bands images, we computed the Afρ parameter, and a dust production proxy [7]. In this work, we will show the magnitude evolution of this comet over 4 years (2017-2022), as well as the gas and dust activity for several months as a function of heliocentric distances

398P/Boattini a new JFC carbon-chain poor comet

E. Jehin, Y. Moulane, J. Manfroid, F. Pozuelos, M. Ferrais, D. Hutsemekers (STAR Institute, University of Liege, Belgium) report that they obtained with TRAPPIST-North (code=Z53, at Oukaimeden Observatory, Morocco) 0.6-m robotic telescope, three sets of observations of the recently recovered comet 398P/Boattini (= 2009 Q4 = 2020 P2, CBET 4829) on November 10, 15 and 20 UT under photometric conditions using HB cometary narrowband filters (Farnham et al. 2000)

Monitoring of the optical spectrum of comet 2I/Borisov at the VLT

2I/Borisov is the first active interstellar comet observed in the Solar Sytem, allowing for the first time to sample the composition of a planetary building block from an extrasolar system. We report on the monitoring of 2I with the FORS low resolution spectrograph of the ESO VLT at Paranal during four months, from November 19, 2019 to March 20, 2020. We collected a dozen spectra at 8 different epochs allowing to follow the evolution of the comet activity and composition around perihelion. We also observed with the same instrumental setup an Oort Cloud comet, C/2019 U6 (Lemmon), at about the same heliocentric and geocentric distance than 2I/Borisov at perihelion (rh=Delta=2 au) and with similar AfRho value and Q(CN) in order to use it as a reference for the Solar System. The usual species are detected in the optical spectrum of 2I (CN, C3, C2, and NH2) and their production rates and abundance ratios are computed. The dust production rate and colors are also derived, compared to C/2019 U6 and other comets of the Solar System, and their evolutions are followed with the heliocentric distance. Fig1. Comparison of the optical spectra of the interstellar comet 2I/Borisov at perihelion (rh=Delta=2,0 au) and the Oort Could comet C/2019 U6 (Lemmon) observed with FORS at the ESO VLT (Paranal Observatory). C/2019/U6 was chosen for comparison as a Solar System comet with a typical composition. It was also at the about the same distances to the Sun and Earth, and it had about the same dust and CN production rates as 2I/Borisov as measured by the TRAPPIST-South telescope

Photometry of 25 Large Main-belt Asteroids with TRAPPIST-North and -South

editorial reviewedDensely sampled lightcurves of 25 large main-belt asteroids were obtained with the TRAPPIST-South (TS) and TRAPPIST-North (TN) telescopes from 2017 to 2021. Those observations took place in support of an ESO large program aiming at observing a representative sample of large asteroids with the ESO VLT for precise shape determination from adaptive optics high-resolution imaging. Synodic rotation periods and lightcurve amplitudes have been determined for all but one target. Six asteroids were observed during two different apparitions. The data have been submitted to the ALCDEF database