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Asteroid Near-Earth

2016 GW221

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(2016 GW221)

Where is it now

Distance from Sun
1.023 AU
True anomaly
158.46°
Distance from Earth
2.016 AU
As of
19 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 — 0.996 AU from the Sun Earth 2016 GW221 — 1.023 AU from the Sun 2016 GW221
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2016 GW221 is 2.016 AU from Earth today (16.8 light-minutes).

In the sky

Right ascension
13h 27m 17s
Declination
-08° 42′ 26″
Constellation
Virgo
Distance from Earth
2.02 AU
Elongation from the Sun
3.05° — 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
0.828 AU
Eccentricity
0.2668
Inclination
3.76°
Orbital period
275.2 days
Perihelion
0.607 AU
Aphelion
1.049 AU
Longitude of ascending node
33.05°
Argument of periapsis
8.86°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 8.7 LD
0.0223 AU
Tisserand (Jupiter)
7.051

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
209
Data arc
9.03 years
First observed
14 April 2016
Last observed
27 April 2025
Residual RMS
0.39 ″
Solution · Otto Matic
18 July 2025

Physical properties

Rotation period
0.29 hours

Visual & observation

Absolute magnitude (H)
24.75

Discovery & classification

Aten Near-Earth Object

Close approaches 115 on record

Flyby geometry
Ecliptic flyby of 2016 GW221 at 2028-03-28 15:57 UTC Top-down view of the ecliptic, Earth at the centre, for the 2028-03-28 15:57 UTC close approach of 2016 GW221. Catalogue miss distance 60.3 LD · 2.32 × 10⁷ km. The curve is the geocentric path from 2028-03-25 to 2028-03-31, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 60.3 LD · 2.32 × 10⁷ km 2028-03-28 15:57 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2028-03-28 15:57 UTC close approach of 2016 GW221. Catalogue miss distance 60.3 LD · 2.32 × 10⁷ km. The curve is the geocentric path from 2028-03-25 to 2028-03-31, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.

JPL Horizons

When (UTC) Body Distance Lunar distances Relative speed
2028-03-28 15:57:00 Earth 0.1549 AU 60.3 LD 10.4 km/s
2031-11-05 01:00:00 Venus 0.0795 AU 30.9 LD 6.1 km/s
2034-09-06 06:16:00 Venus 0.1002 AU 39.0 LD 13.8 km/s
2038-08-27 06:02:00 Venus 0.0346 AU 13.5 LD 10.4 km/s
2041-06-21 12:23:00 Venus 0.0304 AU 11.8 LD 7.6 km/s
2048-05-21 17:15:00 Venus 0.1152 AU 44.8 LD 7.7 km/s
2051-04-15 11:11:00 Venus 0.1405 AU 54.7 LD 15.7 km/s
2055-04-07 23:39:00 Venus 0.0515 AU 20.0 LD 11.3 km/s
2056-06-02 06:08:00 Earth 0.1219 AU 47.4 LD 9.3 km/s
2058-02-08 14:18:00 Venus 0.0715 AU 27.8 LD 6.3 km/s

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

Sources