In this work , we present the results of an observational study of 2I/Borisov carried out with the 10.4-m Gran Telescopio Canarias ( GTC ) and the 3.6-m Telescopio Nazionale Galileo ( TNG ) , both telescopes located at the Roque de Los Muchachos Observatory , in the island of La Palma ( Spain ) .
The study includes images in the visible and near-infrared , as well as visible spectra in the 3600 – 9200 Å wavelength range . N -body simulations were also performed to explore its orbital evolution and Galactic kinematic context .
The comet ’ s dust continuum and near-infrared colours are compatible with those observed for Solar system comets .
From its visible spectrum on the nights of 2019 , September 24 and 26 we measured CN gas production rates Q ( CN ) = ( 2.3 \pm 0.4 ) \times 10 ^ { 24 } mol s ^ { -1 } and Q ( CN ) = ( 9.5 \pm 0.2 ) \times 10 ^ { 24 } mol s ^ { -1 } , respectively , in agreement with measurements reported by other authors on similar nights .
We also obtained an upper limit for the C _ { 2 } production rate of Q ( C _ { 2 } ) < ( 4.5 \pm 0.1 ) \times 10 ^ { 24 } mol s ^ { -1 } .
Dust modelling results indicate a moderate dust production rate of \sim 50 kg s ^ { -1 } at heliocentric distance r _ { h } =2.6 au , with a differential power-law dust size distribution of index \sim –3.4 , within the range reported for many comet comae .
Our simulations show that the Galactic velocity of 2I/Borisov matches well that of known stars in the solar neighbourhood and also those of more distant regions of the Galactic disc .