This object moves — fetching its current position…
Score breakdown
· 3 badges
25 pts · Uncommon
Uncommon34 pts → Rare
Centaur: adrift between the giants+20
Kuiper-belt object+5
Catalogue designation only+0
Total score25
9 more points to reach Rare.
Badges
❄️Kuiper-belt object· +5
🔢Catalogue designation only
🦌Centaur: adrift between the giants· +20
✨ Trivia
What it actually is
🛸Its orbit family. A centaur, wandering between the orbits of Jupiter and Neptune on a path nothing can stabilise. Half asteroid and half comet, and gone from this orbit within a few million years.
🌞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 13.2 years.
🥏How far it roams. Its orbit swings between 2.14 and 9.04 AU from the Sun.
Sense of scale
🧱Sense of scale. In everyday terms it is roughly 0.2× the height of Mount Everest.
Standing on it
🥶Sunlight there. Even at its closest the sunlight is only about 22% as strong as Earth's.
🦘Don't jump. Escape velocity here is only around 0.85 m/s. A determined jump would launch you off it and into your own orbit around the Sun.
By the numbers
📐Estimated size. Nobody has measured its size directly. Assuming it reflects light like a typical asteroid, its brightness implies something roughly 1.4 km across.
Properties
aphelion au
9.04
designation
2013 BU1
eccentricity
0.6177
full name
(2013 BU1)
h mag
17
inclination
5.98
mean motion deg day
0.0747
moid au
1.16
name
2013 BU1
number only
yes
orbit class
CEN
perihelion au
2.135
semi major au
5.586
About 2013 BU1
2013 BU1 is an uncommon kbo. It swings within 2.135 AU of the Sun at perihelion.
A centaur, wandering between the orbits of Jupiter and Neptune on a path nothing can stabilise. Half asteroid and half comet, and gone from this orbit within a few million years.
How to see it
Like any astronomical target, 2013 BU1 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 2013 BU1 is an uncommon kbo
2013 BU1 scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.
That score comes from 3 science badges — Kuiper-belt object, Catalogue designation only and Centaur: adrift between the giants — 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.