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Asteroid

Juewa

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139 Juewa (A874 TA)

Where is it now

Distance from Sun
3.135 AU
True anomaly
143.56°
Distance from Earth
3.04 AU
As of
21 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 — 0.995 AU from the Sun Earth Juewa — 3.135 AU from the Sun Juewa
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Juewa is 3.04 AU from Earth today (25.3 light-minutes).

In the sky

Right ascension
19h 52m 28s
Declination
-29° 30′ 37″
Constellation
Sagittarius
Distance from Earth
3.04 AU
Elongation from the Sun
85.9° — 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
2.786 AU
Eccentricity
0.1703
Inclination
10.87°
Orbital period
4.65 years
Perihelion
2.311 AU
Aphelion
3.261 AU
Longitude of ascending node
1.66°
Argument of periapsis
167.37°
Epoch · J2000
2461200.5
Orbit class · MBA
Main-belt asteroid
Earth MOID · 513.3 LD
1.319 AU
Tisserand (Jupiter)
3.284

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
9,304
Data arc
145 years
First observed
28 March 1881
Last observed
5 April 2026
Residual RMS
0.28 ″
Solution · Otto Matic
5 June 2026

Physical properties

Mean radius
76 km
Rotation period
20.99 hours

Visual & observation

Geometric albedo
0.052
Absolute magnitude (H)
8.04
Colour index (B–V)
0.69
Spectral type (SMASS)
X
Spectral type (Tholen)
CP
Colour index (U–B)
0.29

Discovery & classification

Discovered by
Watson, J. C.
Discovery date
10 October 1874
Discovery site
Peking

Also known as 139 · A874 TA

Main-Belt Asteroid Named

Close approaches 9 on record

When (UTC) Body Distance Lunar distances Relative speed
2046-01-24 16:02:00 Juptr 1.713 AU 666.7 LD 3.1 km/s
2068-11-15 03:41:00 Juptr 1.9448 AU 756.8 LD 3 km/s
2130-01-19 17:36:00 Juptr 1.8234 AU 709.6 LD 3 km/s
2152-11-18 17:43:00 Juptr 1.7061 AU 664.0 LD 3.1 km/s
2175-09-11 09:33:00 Juptr 1.9387 AU 754.5 LD 3.1 km/s

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

Sources