This object moves — fetching its current position…
Score breakdown
· 5 badges
25 pts · Uncommon
Uncommon34 pts → Rare
Potentially hazardous+12
Near-Earth object+5
Apollo: crosses Earth's orbit+4
Stony asteroid+4
Catalogue designation only+0
Total score25
9 more points to reach Rare.
Badges
🌠Near-Earth object· +5
⚠️Potentially hazardous· +12
🔢Catalogue designation only
🏛️Apollo: crosses Earth's orbit· +4
🧗Stony asteroid· +4
✨ 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 8449 megatons — about 169 times the largest bomb ever detonated.
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 1.01 AU of the Sun — inside the orbit of Mars.
🔁One lap. A single orbit around the Sun takes it about 1.8 years.
🥏How far it roams. Its orbit swings between 1.01 and 1.91 AU from the Sun.
Sense of scale
🧱Sense of scale. In everyday terms it is about 4.8 football pitches across.
Standing on it
🦘Don't jump. Escape velocity here is only around 0.31 m/s. A determined jump would launch you off it and into your own orbit around the Sun.
Properties
aphelion au
1.91
designation
171839
eccentricity
0.3107
full name
171839 (2001 JM1)
h mag
19.23
inclination
17.08
mean motion deg day
0.5583
moid au
0.0465
name
(171839) 2001 JM1
number only
yes
orbit class
APO
perihelion au
1.007
pha
yes
rotation period h
5.7516
semi major au
1.461
spec taxonomy
S
spect
S
About (171839) 2001 JM1
(171839) 2001 JM1 is an uncommon neo. It has spectral type S and swings within 1.007 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.
How to see it
Like any astronomical target, (171839) 2001 JM1 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 (171839) 2001 JM1 is an uncommon neo
(171839) 2001 JM1 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 5 science badges — Near-Earth object, Potentially hazardous, Catalogue designation only, Apollo: crosses Earth's orbit and Stony asteroid — 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.