C89
NGC 6087
천체 데이터
- 카탈로그 지정명
- C89
- 유형
- OpenCluster
- 별자리
- Norma
- 등급
- 5.4
- 적경
- 16h 18m 48.0s
- 적위
- -57° 55' 58.8"
- 거리
- 2,900 광년
- 각크기
- 12
서베이 이미지
서베이 이미지 로드 중…
C89 소개
설명
NGC 6087 is a bright open cluster in Norma, about 3,300 light-years away. It contains about 40 stars within 12 arcminutes, with the brightest member being the Cepheid variable star S Normae, which pulsates between magnitudes 6.1 and 6.8 over 9.75 days.
관측 팁
A fine cluster for binoculars and small telescopes. The bright Cepheid S Normae stands out at the cluster's center. Monitoring its brightness changes over a week is a rewarding project. Best from southern locations in summer.
역사
Discovered by Nicolas Louis de Lacaille in 1751 from South Africa. S Normae was discovered as a Cepheid variable by Roberts in 1895 and is one of the most accessible Cepheid variables for amateur observation.
재미있는 사실
S Normae's membership in this cluster was crucial for calibrating the Cepheid period-luminosity relation, since the cluster's distance provides an independent distance measurement for the Cepheid — a key rung on the cosmic distance ladder.
커뮤니티 사진 (1)
Credit: Roberto Mura. License: CC BY-SA 3.0. (Wikimedia Commons)
Skybred Mar 2, 2026