About C/2015 G2 (MASTER)
C/2015 G2 (MASTER) is a rare comet. It swings within 0.78 AU of the Sun at perihelion.
On a hyperbolic orbit: it is moving too fast for the Sun's gravity to hold on to it.
Rare comet 40 EP
C/2015 G2 (MASTER)
Position computed live · sbdb
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Live ephemeris
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Score breakdown
· 4 badgesRare 50 pts → Epic
- Hyperbolic comet (one pass, then gone) +18
- Retrograde orbit +8
- Has a proper name +8
- Comet +6
Total score 40
10 more points to reach Epic.
Badges
- Comet · +6
- Retrograde orbit · +8
- Has a proper name · +8
- Hyperbolic comet (one pass, then gone) · +18
Trivia
Hard to believe
- Against the traffic. It goes round the Sun backwards, against the direction every planet and almost everything else travels.
What it actually is
- Its orbit family. On a hyperbolic orbit: it is moving too fast for the Sun's gravity to hold on to it.
- Closest approach. At its nearest it comes within 0.78 AU of the Sun — inside the orbit of Earth.
- One-way trip. On a hyperbolic path — it will leave the Solar System and never return.
Standing on it
- Growing a tail. Once inside roughly the orbit of Mars the ice starts turning straight to gas, blowing out the coma and tail that make a comet a comet.
- Tail. Its tail always points away from the Sun, never trailing behind its motion — it is blown, not dragged.
By the numbers
- Made of. A comet is a dirty snowball: water ice, frozen carbon dioxide and dust, held together loosely enough that some simply crumble when the Sun warms them.
What's in a name
- Named. Notable enough to have earned a proper name, not just a catalogue number.
Properties
- designation
- 2015 G2
- eccentricity
- 1.0004
- full name
- C/2015 G2 (MASTER)
- inclination
- 147.56
- mean motion deg day
- 0
- moid au
- 0.146
- name
- C/2015 G2 (MASTER)
- named
- yes
- orbit class
- HYP
- perihelion au
- 0.78
- semi major au
- -1974
How to see it
Like any astronomical target, C/2015 G2 (MASTER) 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 C/2015 G2 (MASTER) is a rare comet
C/2015 G2 (MASTER) scores 40 points on Spacedle's rarity scale, which places it in the rare tier. Another 10 points would lift it into a rarer tier.
That score comes from 4 science badges — Comet, Retrograde orbit, Has a proper name and Hyperbolic comet (one pass, then gone) — 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.