Skip to content
Public Universe
Asteroid

Protogeneia

Add to an observing list or journal →

147 Protogeneia (A875 NA)

Where is it now

Distance from Sun
3.079 AU
True anomaly
33.93°
Distance from Earth
2.086 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 Protogeneia — 3.079 AU from the Sun Protogeneia
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Protogeneia is 2.086 AU from Earth today (17.3 light-minutes).

In the sky

Right ascension
01h 26m 44s
Declination
+11° 10′ 39″
Constellation
Pisces
Distance from Earth
2.09 AU
Elongation from the Sun
175.13° — near opposition — up most of the night

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
3.137 AU
Eccentricity
0.0218
Inclination
1.93°
Orbital period
5.56 years
Perihelion
3.068 AU
Aphelion
3.205 AU
Longitude of ascending node
248.19°
Argument of periapsis
103.45°
Epoch · J2000
2461200.5
Orbit class · MBA
Main-belt asteroid
Earth MOID · 802.0 LD
2.0609 AU
Tisserand (Jupiter)
3.21

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
6,793
Data arc
150.2 years
First observed
25 September 1875
Last observed
9 December 2025
Residual RMS
0.34 ″
Solution · Otto Matic
5 June 2026

Physical properties

Mean radius
66 km
Rotation period
7.85 hours

Visual & observation

Geometric albedo
0.049
Absolute magnitude (H)
8.72
Colour index (B–V)
0.68
Spectral type (SMASS)
C
Spectral type (Tholen)
C
Colour index (U–B)
0.29

Discovery & classification

Discovered by
Schulhof, L.
Discovery date
10 July 1875
Discovery site
Vienna

Also known as 147 · A875 NA

Main-Belt Asteroid Named

Close approaches 9 on record

When (UTC) Body Distance Lunar distances Relative speed
2071-09-01 12:51:00 Juptr 1.9535 AU 760.3 LD 3.8 km/s
2082-01-26 10:07:00 Juptr 1.9413 AU 755.5 LD 3.8 km/s
2155-04-24 00:54:00 Juptr 1.9915 AU 775.0 LD 3.9 km/s
2165-09-20 02:14:00 Juptr 1.9384 AU 754.4 LD 3.8 km/s
2176-02-14 09:51:00 Juptr 1.9819 AU 771.3 LD 3.8 km/s

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

Sources