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Score breakdown
· 6 badges
44 pts · Rare
Rare50 pts → Epic
Metal-rich asteroid+14
Large body (100-500 km)+12
Notably bright (low H)+8
Has a proper name+8
Asteroid+1
Main-belt asteroid+1
Total score44
6 more points to reach Epic.
Badges
🪨Asteroid· +1
🗿Large body (100-500 km)· +12
💡Notably bright (low H)· +8
🏷️Has a proper name· +8
🥌Main-belt asteroid· +1
⚙️Metal-rich asteroid· +14
✨ Trivia
What it actually is
🛸Its orbit family. A main-belt asteroid, one of millions circling between Mars and Jupiter. Despite the films, the belt is so empty that every spacecraft sent through it has crossed without aiming for anything.
🌞Closest approach. At its nearest it comes within 2.13 AU of the Sun — inside the orbit of Jupiter.
🔁One lap. A single orbit around the Sun takes it about 4.5 years.
🥏How far it roams. Its orbit swings between 2.13 and 3.33 AU from the Sun.
Sense of scale
🧱Sense of scale. In everyday terms it is about 5.1× the length of Manhattan island.
🚶Walk around it. Walking its equator at a steady pace, eight hours a day, would take about 8.6 days.
Standing on it
🥶Sunlight there. Even at its closest the sunlight is only about 22% as strong as Earth's.
By the numbers
📐Size. Roughly 110 km across.
Properties
albedo
0.0676
aphelion au
3.33
designation
140
diameter km
109.79
eccentricity
0.2182
full name
140 Siwa (A874 TB)
h mag
8.45
inclination
3.19
mean motion deg day
0.2185
moid au
1.12
name
Siwa
named
yes
orbit class
MBA
perihelion au
2.134
rotation period h
34.445
semi major au
2.73
spec taxonomy
Xc
spect
Xc
About Siwa
Siwa is a rare asteroid. It has spectral type Xc and swings within 2.134 AU of the Sun at perihelion.
A main-belt asteroid, one of millions circling between Mars and Jupiter. Despite the films, the belt is so empty that every spacecraft sent through it has crossed without aiming for anything.
How to see it
Like any astronomical target, Siwa is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. Because it moves against the background stars, the live position panel on this page tracks where it is right now. The visibility panel above works out tonight's viewing window for your saved location.
Why Siwa is a rare asteroid
Siwa scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.
That score comes from 6 science badges — Asteroid, Large body (100-500 km), Notably bright (low H), Has a proper name, Main-belt asteroid and Metal-rich asteroid — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.