About NGC 3699
NGC 3699 is an uncommon nebula. It sits in the constellation Cen and shines at apparent magnitude 11.3.
A planetary nebula: the shed outer atmosphere of a dying Sun-like star, lit from within by the naked stellar core left behind.
Uncommon nebula 30 EP
NGC 3699
RA 171.9881° · Dec -59.9581° · openngc
Score breakdown
· 3 badgesUncommon 34 pts → Rare
- Planetary nebula (a dying star's shell) +12
- Coming towards us +10
- Nebula +8
Total score 30
4 more points to reach Rare.
Badges
- Nebula · +8
- Planetary nebula (a dying star's shell) · +12
- Coming towards us · +10
Trivia
What it actually is
- What it actually is. A planetary nebula: the shed outer atmosphere of a dying Sun-like star, lit from within by the naked stellar core left behind.
Find it in the sky
- How to spot it. At magnitude 11.3 you'll want a small backyard telescope, over in Centaurus.
- Southern sky. It rides the southern half of the sky — an easier target the further south 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. Its teal-green comes from doubly-ionised oxygen at 501 nanometres, and its red from hydrogen at 656 — colours no ordinary object on Earth produces.
What's in a name
- A misleading name. 'Planetary nebula' is a 240-year-old mistake. William Herschel coined it in the 1780s because these round greenish discs resembled the planet Uranus he had just discovered. There are no planets involved whatsoever.
How we came to know it
- The New General Catalogue. Its NGC number comes from J. L. E. Dreyer's 1888 catalogue, itself built on decades of sky sweeps by William Herschel and his sister Caroline.
Properties
- constellation
- Cen
- dso type
- PN
- mag
- 11.3
- name
- NGC 3699
- radial velocity kms
- -16
- size arcmin
- 0.75
How to see it
Look for NGC 3699 in the constellation Cen. At apparent magnitude 11.3, a small backyard telescope will bring it into view.
Like any astronomical target, NGC 3699 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 NGC 3699 is an uncommon nebula
NGC 3699 scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 points would lift it into a rarer tier.
That score comes from 3 science badges — Nebula, Planetary nebula (a dying star's shell) and Coming towards us — 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.