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Comet

NEOWISE

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C/2021 A2 (NEOWISE)

NEOWISE is a comet in the Comet orbit class. Its orbit takes it from 1.41 AU to 513.96 AU from the Sun; one orbit takes 4,136.7 years. Orbit from the JPL solution of 2 January 2025.

Where is it now

Distance from Sun
16.617 AU
True anomaly
146.61°
Distance from Earth
16.37 AU
As of
24 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.

Sun Earth — 0.994 AU from the Sun Earth NEOWISE — 16.617 AU from the Sun NEOWISE
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. NEOWISE is 16.37 AU from Earth today (2.3 light-hours).

In the sky

Right ascension
20h 25m 45s
Declination
+35° 11′ 15″
Constellation
Cygnus
Distance from Earth
16.38 AU
Elongation from the Sun
102.16° — well clear of the Sun

Favours the northern hemisphere; low or below the horizon from far south.

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
257.688 AU
Eccentricity
0.9945
Inclination
106.98°
Orbital period
4,136.7 years
Perihelion
1.413 AU
Aphelion
513.963 AU
Longitude of ascending node
125.24°
Argument of periapsis
338.85°
Epoch · J2000
2459265.5
Orbit class · COM
Comet
Earth MOID · 181.8 LD
0.467 AU
Tisserand (Jupiter)
-0.41

Orbit quality

Observations used
980
Data arc
126 days
First observed
3 January 2021
Last observed
9 May 2021
Residual RMS
0.54 ″
Solution · Otto Matic
2 January 2025

Visual & observation

Absolute magnitude (H)
15
Total magnitude M₁ · K₁ 4.5
15

Discovery & classification

Also known as 2021 A2

Named

Sources