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Asteroid Near-Earth Potentially hazardous

513171

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513171 (2004 MD6)

Where is it now

Distance from Sun
1.311 AU
True anomaly
153.7°
Distance from Earth
1.815 AU
As of
22 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 513171 — 1.311 AU from the Sun 513171
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 513171 is 1.815 AU from Earth today (15.1 light-minutes).

In the sky

Right ascension
16h 54m 01s
Declination
-13° 47′ 51″
Constellation
Ophiuchus
Distance from Earth
1.82 AU
Elongation from the Sun
44.65° — near the Sun — look low at dusk or dawn

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
0.951 AU
Eccentricity
0.5631
Inclination
29.32°
Orbital period
338.7 days
Perihelion
0.415 AU
Aphelion
1.486 AU
Longitude of ascending node
263.83°
Argument of periapsis
231.46°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 3.5 LD
0.0091 AU
Tisserand (Jupiter)
6.088

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
174
Data arc
16.3 years
First observed
23 June 2004
Last observed
11 October 2020
Residual RMS
0.57 ″
Solution · Otto Matic
14 April 2021

Visual & observation

Absolute magnitude (H)
20.48

Discovery & classification

Discovered by
LINEAR
Discovery date
23 June 2004
Discovery site
Socorro

Also known as 2004 MD6

Aten Near-Earth Object Potentially Hazardous Asteroid

Close approaches 113 on record

Flyby geometry
Ecliptic flyby of 513171 at 2029-06-19 07:58 UTC Top-down view of the ecliptic, Earth at the centre, for the 2029-06-19 07:58 UTC close approach of 513171. Catalogue miss distance 40.6 LD · 1.56 × 10⁷ km. The curve is the geocentric path from 2029-06-16 to 2029-06-22, 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 40.6 LD · 1.56 × 10⁷ km 2029-06-19 07:58 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2029-06-19 07:58 UTC close approach of 513171. Catalogue miss distance 40.6 LD · 1.56 × 10⁷ km. The curve is the geocentric path from 2029-06-16 to 2029-06-22, 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
2029-06-19 07:58:00 Earth 0.1043 AU 40.6 LD 24.1 km/s
2030-06-14 00:24:00 Earth 0.2999 AU 116.7 LD 16.3 km/s
2033-11-12 12:44:00 Earth 0.4211 AU 163.9 LD 23.8 km/s
2034-10-06 08:50:00 Earth 0.4979 AU 193.8 LD 27.7 km/s
2041-07-02 05:19:00 Earth 0.4094 AU 159.3 LD 32.8 km/s
2042-06-16 00:48:00 Moon 0.0083 AU 3.2 LD 21.5 km/s
2042-06-16 04:14:00 Earth 0.0097 AU 3.8 LD 21.6 km/s
2043-06-18 15:48:00 Earth 0.3873 AU 150.7 LD 15.8 km/s
2045-12-14 02:37:00 Earth 0.4868 AU 189.5 LD 27.2 km/s
2046-11-03 04:53:00 Earth 0.4164 AU 162.0 LD 23.6 km/s

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

Sources