About YORP
YORP is an epic neo. It swings within 0.775 AU of the Sun at perihelion.
An Apollo-class object: its orbit is wider than Earth's but crosses it. Most known Earth-crossers belong to this family.
Epic neo 57 EP
YORP
Position computed live · sbdb
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Live ephemeris
This object moves — fetching its current position…
Score breakdown
· 5 badgesEpic 78 pts → Anomaly
- Spinning past the rubble-pile limit +22
- Passes within two lunar distances of Earth's orbit +18
- Has a proper name +8
- Near-Earth object +5
- Apollo: crosses Earth's orbit +4
Total score 57
21 more points to reach Anomaly.
Badges
- Near-Earth object · +5
- Has a proper name · +8
- Apollo: crosses Earth's orbit · +4
- Spinning past the rubble-pile limit · +22
- Passes within two lunar distances of Earth's orbit · +18
Trivia
What it actually is
- Its orbit family. An Apollo-class object: its orbit is wider than Earth's but crosses it. Most known Earth-crossers belong to this family.
- Closest approach. At its nearest it comes within 0.78 AU of the Sun — inside the orbit of Earth.
- One lap. A single orbit around the Sun takes it about 1 years.
- How far it roams. Its orbit swings between 0.77 and 1.24 AU from the Sun.
Sense of scale
- Sense of scale. In everyday terms it is about 1 football pitches across.
Standing on it
- Don't jump. Escape velocity here is only around 0.06 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 104 metres across.
What's in a name
- Named. Notable enough to have earned a proper name, not just a catalogue number.
Properties
- aphelion au
- 1.24
- designation
- 54509
- eccentricity
- 0.23
- full name
- 54509 YORP (2000 PH5)
- h mag
- 22.66
- inclination
- 1.6
- mean motion deg day
- 0.977
- moid au
- 0.0005
- name
- YORP
- named
- yes
- orbit class
- APO
- perihelion au
- 0.775
- rotation period h
- 0.2029
- semi major au
- 1.006
How to see it
Like any astronomical target, YORP 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 YORP is an epic neo
YORP scores 57 points on Spacedle's rarity scale, which places it in the epic tier. Another 21 points would lift it into a rarer tier.
That score comes from 5 science badges — Near-Earth object, Has a proper name, Apollo: crosses Earth's orbit, Spinning past the rubble-pile limit and Passes within two lunar distances of Earth's orbit — 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.