← Back to dex - Centaur: adrift between the giants +20
- Kuiper-belt object +5
- Steeply tilted orbit (i > 40°) +4
- Catalogue designation only +0
Total score 29
5 more points to reach Rare.
Badges
- ❄️ Kuiper-belt object · +5
- 🔢 Catalogue designation only
- 🦌 Centaur: adrift between the giants · +20
- 📏 Steeply tilted orbit (i > 40°) · +4
✨ 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 3.41 AU of the Sun — inside the orbit of Jupiter.
- 🔁 One lap. A single orbit around the Sun takes it about 15.3 years.
- 🥏 How far it roams. Its orbit swings between 3.41 and 8.95 AU from the Sun.
Sense of scale
- 🧱 Sense of scale. In everyday terms it is roughly 0.5× the height of Mount Everest.
By the numbers
- 📐 Estimated size. Nobody has measured its size directly. Assuming it reflects light like a typical asteroid, its brightness implies something roughly 4.3 km across.
What's in a name
- 🔢 Designation. Known only by its catalogue designation — no name yet.
Properties
- aphelion au
- 8.95
- designation
- 540205
- eccentricity
- 0.4484
- full name
- 540205 (2017 RS17)
- h mag
- 14.56
- inclination
- 42.71
- mean motion deg day
- 0.0642
- moid au
- 2.64
- name
- (540205) 2017 RS17
- number only
- yes
- orbit class
- CEN
- perihelion au
- 3.406
- semi major au
- 6.176
About (540205) 2017 RS17
(540205) 2017 RS17 is an uncommon kbo. It swings within 3.406 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, (540205) 2017 RS17 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 (540205) 2017 RS17 is an uncommon kbo
(540205) 2017 RS17 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.
That score comes from 4 science badges — Kuiper-belt object, Catalogue designation only, Centaur: adrift between the giants and Steeply tilted orbit (i > 40°) — 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.