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Asteroid Near-Earth

9400

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9400 (1994 TW1)

Where is it now

Distance from Sun
3.924 AU
True anomaly
194.27°
Distance from Earth
4.446 AU
As of
11 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.

Orbit of Mercury Orbit of Venus Orbit of Mars Sun Earth — 0.998 AU from the Sun Earth 9400 — 3.924 AU from the Sun 9400
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 9400 is 4.446 AU from Earth today (37.0 light-minutes).

In the sky

Right ascension
15h 34m 39s
Declination
-50° 27′ 37″
Constellation
Norma
Distance from Earth
4.45 AU
Elongation from the Sun
52.46° — near the Sun — look low at dusk or dawn

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
2.588 AU
Eccentricity
0.5806
Inclination
35.98°
Orbital period
4.16 years
Perihelion
1.086 AU
Aphelion
4.091 AU
Longitude of ascending node
3.33°
Argument of periapsis
62.19°
Epoch · J2000
2461200.5
Orbit class · AMO
Amor
Earth MOID · 111.0 LD
0.2852 AU
Tisserand (Jupiter)
2.94

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
2,285
Data arc
34.03 years
First observed
18 March 1991
Last observed
29 March 2025
Residual RMS
0.48 ″
Solution · Otto Matic
30 March 2025

Physical properties

Mean radius
1.85 km
Rotation period
4.05 days

Visual & observation

Geometric albedo
0.155
Absolute magnitude (H)
14.84
Spectral type (SMASS)
Sr

Discovery & classification

Discovered by
Helin, E. F., Lawrence, K. J.
Discovery date
9 October 1994
Discovery site
Palomar

Also known as 1994 TW1

Amor Near-Earth Object

Close approaches 3 on record

When (UTC) Body Distance Lunar distances Relative speed
2086-07-07 01:52:00 Mars 0.0629 AU 24.5 LD 21.5 km/s
2144-10-25 19:22:00 Mars 0.0529 AU 20.6 LD 21.4 km/s

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

Sources