About HD 100973
HD 100973 is a trash star. It sits in the constellation Leo, shines at apparent magnitude 8.89 and has spectral type G5.
Its spectrum reads G5 — a G-type star: the very same spectral class as our own Sun.
Trash star 14 EP
HD 100973
RA 174.3530° · Dec 25.8027° · star
Score breakdown
· 3 badgesTrash 15 pts → Common
- Sun-like G-type star +8
- Star +3
- On the zodiac +3
Total score 14
1 more point to reach Common.
Badges
- Star · +3
- On the zodiac · +3
- Sun-like G-type star · +8
Trivia
Hard to believe
- True brightness. It pours out about 2.4 million times as much light as the Sun. It only looks ordinary because it is so far away.
What it actually is
- Spectral class. Its spectrum reads G5 — a G-type star: the very same spectral class as our own Sun.
Find it in the sky
- How to spot it. At magnitude 8.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Leo.
- Northern sky. It rides the northern half of the sky — an easier target the further north you are.
- Best time of year. It stands highest in the middle of the night around March — that's when to go looking.
Its true colour
- Its true colour. Measured through blue and visual filters it comes out orange (B−V 0.9) — cooler than the Sun, and the kind of star that burns steadily for tens of billions of years.
- Why no green stars. No star ever looks green: a surface hot enough to peak in green also floods out plenty of red and blue, and your eye blends the mixture back to white.
By the numbers
- Surface temperature. Its colour puts the surface at roughly 4870 K, against the Sun's 5778 K.
Properties
- absmag
- -11.11
- bv
- 0.95
- constellation
- Leo
- luminosity
- 2421029.0467
- mag
- 8.89
- name
- HD 100973
- spect
- G5
How to see it
Look for HD 100973 in the constellation Leo. At apparent magnitude 8.89, it is an easy target for binoculars.
Like any astronomical target, HD 100973 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. The visibility panel above works out tonight's viewing window for your saved location.
Why HD 100973 is a trash star
HD 100973 scores 14 points on Spacedle's rarity scale, which places it in the trash tier. Another 1 point would lift it into a rarer tier.
That score comes from 3 science badges — Star, On the zodiac and Sun-like G-type star — 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.