Recently, I wrote C/2017 T2 (PANSTARRS) comet as perhaps the brightest comet of 2020. Fortunately, it had a serious rival which, if it didn't fall apart, would be much brighter than C/2017 T2 (PANSTARRS). The C/2019 Y4 (ATLAS) comet was discovered by the Asteroid Terrestrial-Impact Last Alert System on December 28, 2019.
The comet soon discovered that its orbit was almost identical to the naked eye comet seen in 1844 (C/1844 Y1). At the turn of 1844/1845, the comet observed under more favorable conditions from the Southern Hemisphere and was about 1 magnitude brightness. According to current calculations, the two comets may be fragments of a comet that came toward the Sun thousands of years ago.
Due to the orbit calculations so far and its brighter appearance than expected, we have the most pessimistic estimation of our comet, even if not with the naked eye, but with smaller binoculars. Looking at the more optimistic estimates, we seem to be hoping for a much more impressive sight. It is estimated that the brightness of the celestial wanderer may be minus magnitude, making it one of the most spectacular comets in recent decades. The brightest estimate is that you may even see daytime (!) skies. This brightness value and viewing angle promise us a beautiful multi-degree long dust and ion tails.
It is important to note that, before we announce the sensational comet around to the world, we need to know the characteristics of comets like this one. The core of a comet with such high activity and close proximity to the Sun is, due to the factors mentioned above, much more unstable and may not easily survive its time of visit. This is, of course, the worst case scenario. The starting point for pessimistic estimates is that such comets suddenly increase their activity (for example, when writing this line at the end of March), but will then drop below their activity. I do not want to take a standpoint, but hope for sure! In the next period, I will closely monitor the comet's activity and try to capture as many pictures as possible.
On March 18, the comet was much brighter than expected. From the coma which is about 6' long, a thin dust tail stretches toward PA 150o. The coma's distinctive green color is due to the two-atom carbon molecules.
This photo was taken with the support of the Nation's Young Talent Scholarship, announced by Ministry of Human Resources, the Human Resources Support Manager and the National Talent Program.
C/2019 Y4 (ATLAS)
R.A. 09 h 30 m 51 s Dec. +66° 54′ 54″
Distance from Sun:
255 million km
Distance from Earth:
164 million km
Coma: 6'; tail: 5' (PA 150°)
18/03/2020 19:57-22:01 UT
Total exposure time:
Tápióbicske, Pest, Hungary
Canon EOS 1300D (modified)
Sky-Watcher Esprit 80/400 mm apochromatic refractor
Sky-Watcher EQ6-R Pro GoTo
Sky-Watcher Field Flattener
Focal ratio, length:
f/5, 400 mm
30 x 180 s
Astro Pixel Processor, PixInsight, Adobe Lightroom, Adobe Photoshop