Skip to content
Public Universe
Comet

ATLAS

Add to an observing list or journal →

427P/ATLAS

Where is it now

Distance from Sun
3.971 AU
True anomaly
206.65°
Distance from Earth
4.958 AU
As of
11 October 2026

Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.

Orbit of Mercury Orbit of Venus Orbit of Mars Sun Earth — 0.998 AU from the Sun Earth ATLAS — 3.971 AU from the Sun ATLAS
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. ATLAS is 4.958 AU from Earth today (41.2 light-minutes).

In the sky

Right ascension
13h 00m 17s
Declination
-14° 38′ 48″
Constellation
Virgo
Distance from Earth
4.96 AU
Elongation from the Sun
7.59° — too close to the Sun to observe

Visible from both hemispheres.

From your location

See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.

How do I find my coordinates?

Google Maps on a computer

  1. Right-click the spot where you'll be observing.
  2. The first line of the menu is the coordinates, e.g. 51.50722, -0.12758 — click it and they're copied.
  3. Paste them above.

Google Maps on a phone

  1. Press and hold the spot to drop a pin.
  2. The coordinates appear in the search bar (or on the pin's card) — tap to copy, then paste above.

A full Google Maps link works too, but the short maps.app.goo.gl share links don't carry coordinates — copy the numbers instead. We round to about a kilometre; that's all the sky calculation needs.

Know your what3words address? Paste it, e.g. ///filled.count.soap. This is optional — the three words are sent to what3words to convert them, and we don't store the address or the result.

Your location stays in your browser and is sent only for this calculation. Using a what3words address is optional; if you do, the three words go to what3words to be converted and we don't record them. Set a location first, then you can save an email alert for this object. See our privacy policy.

Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.

Orbital elements

Semi-major axis
3.171 AU
Eccentricity
0.313
Inclination
11.85°
Orbital period
5.65 years
Perihelion
2.178 AU
Aphelion
4.163 AU
Longitude of ascending node
252.39°
Argument of periapsis
99.94°
Epoch · J2000
2458079.5
Orbit class · ETc
Encke-type comet
Earth MOID · 470.9 LD
1.21 AU
Tisserand (Jupiter)
3.092

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
442
Data arc
3.89 years
First observed
22 July 2017
Last observed
13 June 2021
Residual RMS
0.52 ″
Solution · Otto Matic
9 June 2026

Visual & observation

Absolute magnitude (H)
10.7
Total magnitude M₁ · K₁ 19.3
10.7

Discovery & classification

Also known as 427P · 427P/2017 S5 · 427P/2021 L6

Named

Close approaches 9 on record

When (UTC) Body Distance Lunar distances Relative speed
2089-04-10 04:29:00 Juptr 1.8955 AU 737.7 LD 3.3 km/s
2100-04-02 22:06:00 Juptr 1.7035 AU 663.0 LD 2.1 km/s
2111-02-28 11:36:00 Juptr 1.6725 AU 650.9 LD 0.6 km/s
2121-12-01 02:35:00 Juptr 1.7759 AU 691.1 LD 1.8 km/s
2132-10-14 11:45:00 Juptr 1.9823 AU 771.5 LD 3.8 km/s

Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.

Sources