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Asteroid Near-Earth Potentially hazardous

2021 MK1

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(2021 MK1)

Where is it now

Distance from Sun
0.892 AU
True anomaly
233.86°
Distance from Earth
0.671 AU
As of
16 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 — 0.997 AU from the Sun Earth 2021 MK1 — 0.892 AU from the Sun 2021 MK1
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 MK1 is 0.671 AU from Earth today (5.6 light-minutes).

In the sky

Right ascension
17h 29m 17s
Declination
+01° 36′ 58″
Constellation
Ophiuchus
Distance from Earth
0.67 AU
Elongation from the Sun
60.81° — well clear of the Sun

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
0.808 AU
Eccentricity
0.288
Inclination
19.24°
Orbital period
265.1 days
Perihelion
0.575 AU
Aphelion
1.04 AU
Longitude of ascending node
273.98°
Argument of periapsis
199°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 0.5 LD
0.0012 AU
Tisserand (Jupiter)
7.155

Orbit quality

Orbit very well determined (uncertainty code 2).

Observations used
316
Data arc
5.19 years
First observed
28 May 2016
Last observed
6 August 2021
Residual RMS
0.39 ″
Solution · Otto Matic
28 July 2026

Visual & observation

Absolute magnitude (H)
21.32

Discovery & classification

Aten Near-Earth Object Potentially Hazardous Asteroid

Close approaches 33 on record

Flyby geometry
Ecliptic flyby of 2021 MK1 at 2029-07-02 14:17 UTC Top-down view of the ecliptic, Earth at the centre, for the 2029-07-02 14:17 UTC close approach of 2021 MK1. Catalogue miss distance 48.0 LD · 1.84 × 10⁷ km. The curve is the geocentric path from 2029-06-29 to 2029-07-05, 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. At closest approach the object is north of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 48.0 LD · 1.84 × 10⁷ km 2029-07-02 14:17 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2029-07-02 14:17 UTC close approach of 2021 MK1. Catalogue miss distance 48.0 LD · 1.84 × 10⁷ km. The curve is the geocentric path from 2029-06-29 to 2029-07-05, 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. At closest approach the object is north of the ecliptic. 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
2029-07-02 14:17:00 Earth 0.1233 AU 48.0 LD 10.1 km/s
2050-06-24 03:17:00 Earth 0.1086 AU 42.3 LD 12.2 km/s
2050-11-26 09:08:00 Venus 0.1331 AU 51.8 LD 17.7 km/s
2058-06-25 02:35:00 Earth 0.0274 AU 10.7 LD 10.8 km/s
2058-11-17 03:12:00 Venus 0.1395 AU 54.3 LD 18 km/s
2066-06-25 18:34:00 Earth 0.0037 AU 1.4 LD 10.6 km/s
2066-06-25 19:27:00 Moon 0.0036 AU 1.4 LD 10.1 km/s
2066-11-17 12:40:00 Venus 0.1289 AU 50.2 LD 17.8 km/s
2077-06-25 04:39:00 Earth 0.0164 AU 6.4 LD 10.7 km/s
2085-12-26 22:31:00 Venus 0.1354 AU 52.7 LD 17.3 km/s

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

Sources