About Ryugu
Ryugu is an anomaly neo. It has spectral type Cb and swings within 0.963 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.
Anomaly neo 79 EP
Ryugu
Position computed live · sbdb
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Live ephemeris
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Score breakdown
· 8 badgesAnomaly 120 pts → Mythic
- Ryugu, sampled by Hayabusa2 +24
- Passes within two lunar distances of Earth's orbit +18
- Darker than charcoal +10
- Has a proper name +8
- Carbonaceous — as old as the solar system +6
- Near-Earth object +5
- Tiny fragment (<1 km) +4
- Apollo: crosses Earth's orbit +4
Total score 79
41 more points to reach Mythic.
Badges
- Near-Earth object · +5
- Tiny fragment (<1 km) · +4
- Has a proper name · +8
- Apollo: crosses Earth's orbit · +4
- Darker than charcoal · +10
- Passes within two lunar distances of Earth's orbit · +18
- Carbonaceous — as old as the solar system · +6
- Ryugu, sampled by Hayabusa2 · +24
Trivia
Handle with care
- What 'hazardous' means. 'Potentially hazardous' is bookkeeping, not a prediction: it means the orbit passes within 0.05 AU of Earth's and the body is big enough to matter. Nothing on that list is known to be on a collision course.
- If it ever hit. A rock this size arriving at a typical 20 km/s would release around 46.8 thousand megatons — enough to devastate a region the size of a small country.
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 0.96 AU of the Sun — inside the orbit of Earth.
- One lap. A single orbit around the Sun takes it about 1.3 years.
- How far it roams. Its orbit swings between 0.96 and 1.42 AU from the Sun.
Sense of scale
- Sense of scale. In everyday terms it is about 8.5 football pitches across.
Standing on it
- Don't jump. Escape velocity here is only around 0.54 m/s. A determined jump would launch you off it and into your own orbit around the Sun.
Properties
- albedo
- 0.045
- aphelion au
- 1.42
- designation
- 162173
- diameter km
- 0.896
- eccentricity
- 0.1911
- full name
- 162173 Ryugu (1999 JU3)
- h mag
- 19.55
- inclination
- 5.87
- mean motion deg day
- 0.7584
- moid au
- 0.0005
- name
- Ryugu
- named
- yes
- orbit class
- APO
- perihelion au
- 0.963
- pha
- yes
- rotation period h
- 7.6326
- semi major au
- 1.191
- spec taxonomy
- Cb
- spect
- Cb
How to see it
Like any astronomical target, Ryugu 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 Ryugu is an anomaly neo
Ryugu scores 79 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 41 points would lift it into a rarer tier.
That score comes from 8 science badges — Near-Earth object, Tiny fragment (<1 km), Has a proper name, Apollo: crosses Earth's orbit, Darker than charcoal, Passes within two lunar distances of Earth's orbit, Carbonaceous — as old as the solar system and Ryugu, sampled by Hayabusa2 — 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.