Follow Comet E1 Atlas Through the July Sky

Comet C/2023 E1 ATLAS skirts the northern pole for summer northern hemisphere observers.

When it comes to comets, even the best predictions may often betray reality. Bright comets may fizzle as they approach the Sun, and fainter comets that ordinarily wouldn’t warrant a second look many suddenly flare into view.

Thankfully, the former seems to be the case with comet C/2023 E1 ATLAS, which has been over-performing expectations as of late, and recently brightened up into the range of binocular visibility at magnitude +10.

To be sure, the comet will probably top out at +8^th to +9^th magnitude through July as it reaches perihelion just outside the Earth’s orbit this coming weekend. The comet is well-placed in the night sky for northern hemisphere campers through Canada Day on July 1^st and Fourth of July weekend.

A Unique Orbit

Comet C/2023 E1 ATLAS was discovered by the Asteroid Terrestrial-Impact Last Alert System (ATLAS) station based at Sutherland, South Africa on the night of March 1^st, 2023. At the time, the comet was a faint +19^th magnitude object, gliding through the constellation Virgo.

The orbit of the comet is an interesting one, with a 38 degree inclination relative to the ecliptic. On just an 85 year orbit, the comet reaches aphelion in early 2066 at 37.7 Astronomical Units (AU) from the Sun, just outside the orbit of the planet Neptune. In fact, the planet seems to share a 2:1 orbital resonance with the comet, as it completes two orbits to every one for Neptune. Though the comet currently has a ‘C’ designation for a long period (versus periodic) comet, that’ll probably change, as 85 years is much less than the 200-year orbital period cutoff defining the two categories.

The 2023 Apparition for Comet E1 ATLAS

It’s rare to see a new short-period comet of note; most of the major ones such as 1P/Halley or 2P/Encke have already been found over the centuries. July is the key month for comet E1 ATLAS, as it starts off the month high to the north in the constellation Ursa Minor, and crosses through Draco and into Cepheus towards closest Earth approach in mid-August. This favorable 2023 apparition may be why the small comet has eluded detection for so long.

Comet E1 ATLAS Through July and August

Here are key celestial dates with destiny for Comet C/2023 E1 ATLAS:

July 1^st – Reaches perihelion, at 1.027 AU from the Sun.

(Full Moon July 3rd)

July 8^th – Reaches maximum northern declination, just nine degrees from the north celestial pole.

July 9^th – Passes just over one degree from the +4.2 magnitude star Epsilon Ursae Minoris.

(Last Quarter Moon July 10th)

July 14^th – Crosses into the constellation Draco the Dragon.

(New Moon July 17th)

(First Quarter Moon July 25th)

July 29^th – Crosses into the constellation of Cepheus the King.

(Full Moon August 1st)

August 1^st – Drops back down below +10^th magnitude?

(Last Quarter Moon August 8th)

August 9^th – Crosses into the constellation Cygnus.

August 10^th – Crosses the galactic equator southward.

(New Moon August 16th)

August 18^th – Passes closest to the Earth, at 0.375 AU distant.

August 22^nd – Crosses into the constellation Pegasus.

(First Quarter Moon August 24th)

August 29^th – Reaches ecliptic opposition, 180 degrees opposite versus the Sun.

Blame it on the Moon

Unfortunately, the Moon reaches Full phase on July 3^rd hampering deep sky observations, Though New phase on the weeks surrounding July 17^th should be ideal to track the comet down. Look for the comet as a small ‘fuzzball’ similar to a globular cluster that stubbornly refuses to snap into focus.

If you have a chance, be sure to check out C/2023 E1 ATLAS… Remember, comets often fail to read prognostications, and can over-achieve versus expectations!