iTelescope ALERT! Asteroid (6478) Gault has a tail!

Telescope view of Asteroid (6478) Gault. The large square is the field of View of T30 (SSO) and the small that of T17 (SSO) the medium rectangle is T5 (Mayhill). The orientation is upside down from the spotters maps.

Asteroid (6478) Gault has been reported to have a comet like tail, from CBET 4594 “The tail/trail first appears in individual ATLAS exposures on 2018 Dec. 8, as identified by Denneau, with a median combined 120-s exposure showing a tail 30″ long in p.a. 290 degrees. There is no evidence of a tail in previous ATLAS imaging in January 2018. An initial analysis using a cometary Finson-Probstein model (cf. website URL http://comet-toolbox.com/FP.html, as perJ.-B. Vincent) shows that both the Dec. 2018 and Jan. 2019 data are consistent with the ejection of material or commencement of activity in early Nov. 2018”. Prevoius images from ATLAS and PanSTARRS show no cometary-like activity back to 2010.

It has been suggested a collision or impact is reponsible for the tail. Ongoing observation of the phenomenon should be undertaken to understand its nature.

Asteroid (6478) Gault is visible from both Northern and southern scopes from with transit around 3:30 am (northernscopes) and 4:30 am (Southern scopes), however, this is just past astronomical twilight, so imaging should begin before this. The Southern scopes have the best view with the asteroid potentially visible from 12:30 am local time.

Asteroid (6478) Gault is currently magnitude 18.7, and will need long exposures on narrow field scopes with tracking for the best results.

iTelescope users Ulrich Eberhard Stickel and Denis Denisenko have achieved images with T30 from SSO. http://scan.sai.msu.ru/~denis/Comet/6478-T30-20190108.jpg

The MPC one line ephemeris is:

06478 14.4 0.15 K194R 289.34905 83.26761 183.55769 22.81135 0.1935870 0.28161558 2.3051451 0 MPO435760 1093 19 1988-2018 0.44 M-v 38h MPC 0000 (6478) Gault 20180209

Example plan for following the asteroid, check filter availability.

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; Single target image example, adjust filter as necessary for chosen scope. 
; 

#trackon
#count 3
#interval 300
#binning 2
#filter Red
06478 14.4 0.15 K194R 289.34905 83.26761 183.55769 22.81135 0.1935870 0.28161558 2.3051451 0 MPO435760 1093 19 1988-2018 0.44 M-v 38h MPC 0000 (6478) Gault 20180209
#shutdown