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Rare kbo 39 EP

2013 SY99

Position computed live · sbdb

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Live ephemeris

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Far-flung orbit (a > 50 AU) +14
  • Trans-Neptunian object +12
  • Notably bright (low H) +8
  • Kuiper-belt object +5
  • Catalogue designation only +0
Total score 39

11 more points to reach Epic.

Badges

  • Kuiper-belt object · +5
  • Notably bright (low H) · +8
  • Catalogue designation only
  • Trans-Neptunian object · +12
  • Far-flung orbit (a > 50 AU) · +14

Trivia

What it actually is

  • Its orbit family. A trans-Neptunian object from the Kuiper Belt, out where the Sun is little more than the brightest star in a very dark sky.
  • One lap. A single orbit around the Sun takes it about 23.2 thousand years.
  • How far it roams. Its orbit swings between 49.91 and 1575.89 AU from the Sun.
  • Wild orbit. Its highly elliptical path swings between scorching and frozen each lap.

Sense of scale

  • Sense of scale. In everyday terms it is about 7.1× the length of Manhattan island.
  • Walk around it. Walking its equator at a steady pace, eight hours a day, would take about 12 days.

By the numbers

  • Estimated size. Nobody has measured its size directly. Assuming it reflects light like a typical asteroid, its brightness implies something roughly 153 km across.

What's in a name

  • Designation. Known only by its catalogue designation — no name yet.

Properties

aphelion au
1575.87
designation
2013 SY99
eccentricity
0.9386
full name
(2013 SY99)
h mag
6.83
inclination
4.23
mean motion deg day
0
moid au
48.9
name
2013 SY99
number only
yes
orbit class
TNO
perihelion au
49.906
semi major au
812.9

About 2013 SY99

2013 SY99 is a rare kbo. It swings within 49.906 AU of the Sun at perihelion.

A trans-Neptunian object from the Kuiper Belt, out where the Sun is little more than the brightest star in a very dark sky.

How to see it

Like any astronomical target, 2013 SY99 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 SY99 is a rare kbo

2013 SY99 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Kuiper-belt object, Notably bright (low H), Catalogue designation only, Trans-Neptunian object and Far-flung orbit (a > 50 AU) — 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.