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Asteroid Near-Earth

303250

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303250 (2004 RU10)

Where is it now

Distance from Sun
1.189 AU
True anomaly
149.77°
Distance from Earth
1.021 AU
As of
20 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 303250 — 1.189 AU from the Sun 303250
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 303250 is 1.021 AU from Earth today (8.5 light-minutes).

In the sky

Right ascension
18h 47m 51s
Declination
-33° 38′ 20″
Constellation
Sagittarius
Distance from Earth
1.03 AU
Elongation from the Sun
72.21° — well clear of the Sun

Favours the southern hemisphere; low or below the horizon from far north.

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
0.904 AU
Eccentricity
0.6569
Inclination
15.91°
Orbital period
314 days
Perihelion
0.31 AU
Aphelion
1.498 AU
Longitude of ascending node
118.94°
Argument of periapsis
65.3°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 41.4 LD
0.1065 AU
Tisserand (Jupiter)
6.36

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
506
Data arc
19.2 years
First observed
7 September 2004
Last observed
21 November 2023
Residual RMS
0.64 ″
Solution · Otto Matic
21 January 2024

Visual & observation

Absolute magnitude (H)
17.91

Discovery & classification

Discovered by
LINEAR
Discovery date
7 September 2004
Discovery site
Socorro

Also known as 2004 RU10

Aten Near-Earth Object

Close approaches 233 on record

Flyby geometry
Ecliptic flyby of 303250 at 2027-08-10 12:16 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-08-10 12:16 UTC close approach of 303250. Catalogue miss distance 53.4 LD · 2.05 × 10⁷ km. The curve is the geocentric path from 2027-08-07 to 2027-08-13, 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 south of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 53.4 LD · 2.05 × 10⁷ km 2027-08-10 12:16 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-08-10 12:16 UTC close approach of 303250. Catalogue miss distance 53.4 LD · 2.05 × 10⁷ km. The curve is the geocentric path from 2027-08-07 to 2027-08-13, 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 south 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
2027-08-10 12:16:00 Earth 0.1373 AU 53.4 LD 19.2 km/s
2029-11-21 20:37:00 Earth 0.3164 AU 123.1 LD 15.6 km/s
2029-12-15 11:05:00 Venus 0.1468 AU 57.1 LD 27.3 km/s
2030-01-07 10:49:00 Mercury 0.021 AU 8.2 LD 34.6 km/s
2030-01-07 10:49:00 Merc 0.021 AU 8.2 LD 34.6 km/s
2030-12-23 14:25:00 Venus 0.1339 AU 52.1 LD 32.3 km/s
2033-08-13 00:32:00 Earth 0.1071 AU 41.7 LD 21.9 km/s
2035-04-12 09:54:00 Venus 0.0777 AU 30.2 LD 29.5 km/s
2035-11-18 14:52:00 Earth 0.3856 AU 150.1 LD 13.5 km/s
2036-01-14 11:09:00 Mercury 0.0631 AU 24.5 LD 40 km/s

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

Sources