Here is another outstanding image of Comet C/2023 E1 (ATLAS) taken on July 13 by Dan Bartlett, showing its long wispy tail.

To the left of the comet coma is double star 41 Draconis (HD 166866), mag 5.74.

https://www.astrobin.com/4mswrp/B/
https://www.universeguide.com/star/88136/41draconis
#Comet #C2023E1 #C2023E1ATLAS
7/n

The green color seen in the coma of Comet C/2023 E1 (ATLAS) and other comets, but not in their tails, is due to emissions from quad-bond Diatomic carbon (aka dicarbon) molecules.

Sunlight heats the comet’s ice and organic material to produce C2 molecules, which break apart in ~2 days before they reach the tail. C2 is excited by solar UV radiation and emits mostly in infrared but its triplet state radiates at 518 nm.

https://physicstoday.scitation.org/do/10.1063/pt.6.1.20220110a/full/
https://www.pnas.org/doi/10.1073/pnas.2113315118
#comet #C2023E1 #dicarbon
6/n

The light curve of comet C/2023 E1 (ATLAS) is shown below. Peak brightness around mag 9 is occurring this week. Objects at mag 6 and lower are visible to the naked eye under good conditions, so a telescope or large binoculars are required to observe this comet.

The magnitude scale is reverse logarithmic: the brighter an object is, the lower its mag number. A difference of 1.0 in mag corresponds to a brightness ratio of 2.512.

Source: http://astro.vanbuitenen.nl/comet/2023E1
#Comet #C2023E1 #C2023E1ATLAS
3/n

C/2023 E1 (ATLAS) was discovered on March 1, 2023 at magnitude 19 using the ATLAS 0.5-m telescope in South Africa.

Perihelion: 1.03 AU, just outside earth's orbit
Distance from earth at closest approach = 0.374 AU (Aug 18)
Aphelion: 37.66 AU (beyond Neptune's orbit)
Inclination: 38.31°
Period = 85 years
(1 AU = 150mil km)

The graphics below show its current location, key parameters and its full inclined orbit.

http://astro.vanbuitenen.nl/comet/2023E1
https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=c%2F2023%20e1&view=VOP
#Comet #C2023E1 #C2023E1ATLAS
2/n