Messier/type:M25 / open cluster
mag/dia/dist:4.6 / 30' / 2,300 ly
constellation:Sagittarius
date/time/place:Apr 21, 01 / 01:00-05:00 / bangkok
trans'y/seeing/l-poll:good / good / medium
telescope:newtonian 4.5" f8.8
eyepieces/power:25mm / 40x
sky atlas page:22
Start from the tea-pot's handle: stars 34,27,38 & 40 (quite fit in FOV of finder scope) stars 40-->27--> points to star 22 "the lid of tea pot" or "Kaus Borealis". From star 22 hop to star mag5 which close to M8,M20 & M21; then hop to stars 13 & 21. Stars 13-->21-->points to M25 (not in quite straight line). M25 appeared as large, loose cluster with faint nebulosity that should be non-resolvable stars.
Refer to text: 30 stars detached, max mag6.7, extends 18 ly, age 89 milloin years. Home
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