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Asteroid Near-Earth

2021 TH13

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(2021 TH13)

Where is it now

Distance from Sun
0.724 AU
True anomaly
42.39°
Distance from Earth
1.659 AU
As of
23 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 — 0.995 AU from the Sun Earth 2021 TH13 — 0.724 AU from the Sun 2021 TH13
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 TH13 is 1.659 AU from Earth today (13.8 light-minutes).

In the sky

Right ascension
13h 10m 18s
Declination
-06° 36′ 25″
Constellation
Virgo
Distance from Earth
1.67 AU
Elongation from the Sun
12.59° — 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
0.965 AU
Eccentricity
0.2947
Inclination
4.72°
Orbital period
346.4 days
Perihelion
0.681 AU
Aphelion
1.25 AU
Longitude of ascending node
23.84°
Argument of periapsis
113.43°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 0.2 LD
0.0004 AU
Tisserand (Jupiter)
6.211

Orbit quality

Orbit reasonably well determined (uncertainty code 5).

Observations used
18
Data arc
8 days
First observed
6 October 2021
Last observed
14 October 2021
Residual RMS
0.56 ″
Solution · Otto Matic
26 October 2021

Visual & observation

Absolute magnitude (H)
28.14

Discovery & classification

Listed by JPL impact monitoring; see the Sentry table for current probabilities.

Aten Near-Earth Object

Close approaches 99 on record

Flyby geometry
Ecliptic flyby of 2021 TH13 at 2035-06-23 06:07 UTC Top-down view of the ecliptic, Earth at the centre, for the 2035-06-23 06:07 UTC close approach of 2021 TH13. Catalogue miss distance 186.4 LD · 7.17 × 10⁷ km. The curve is the geocentric path from 2035-06-20 to 2035-06-26, 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 186.4 LD · 7.17 × 10⁷ km 2035-06-23 06:07 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2035-06-23 06:07 UTC close approach of 2021 TH13. Catalogue miss distance 186.4 LD · 7.17 × 10⁷ km. The curve is the geocentric path from 2035-06-20 to 2035-06-26, 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
2035-06-23 06:07:00 Earth 0.479 AU 186.4 LD 22.7 km/s
2036-04-15 11:52:00 Venus 0.0164 AU 6.4 LD 7.5 km/s
2036-06-08 06:49:00 Earth 0.1784 AU 69.4 LD 13.5 km/s
2037-06-05 20:39:00 Earth 0.1457 AU 56.7 LD 5.2 km/s
2038-03-08 13:40:00 Earth 0.2932 AU 114.1 LD 10.1 km/s
2038-08-08 08:54:00 Earth 0.2532 AU 98.5 LD 7.1 km/s
2039-01-22 16:11:00 Earth 0.3053 AU 118.8 LD 10.5 km/s
2039-09-28 01:09:00 Earth 0.1692 AU 65.8 LD 6 km/s
2040-10-14 06:16:00 Earth 0.1167 AU 45.4 LD 12.1 km/s
2041-10-01 17:00:00 Earth 0.4187 AU 162.9 LD 21.2 km/s

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

Sources