{"id":32,"date":"2004-10-03T20:00:00","date_gmt":"2004-10-03T20:00:00","guid":{"rendered":"http:\/\/perezmedia.net\/beltofvenus\/2004\/10\/03\/m7_ptolemys_clu\/"},"modified":"2004-10-03T20:00:00","modified_gmt":"2004-10-03T20:00:00","slug":"m7_ptolemys_clu","status":"publish","type":"post","link":"https:\/\/perezmedia.net\/beltofvenus\/2004\/10\/03\/m7_ptolemys_clu\/","title":{"rendered":"Messier 7 – Ptolemy’s Cluster"},"content":{"rendered":"

<\/p>\n

Observation Notes:<\/b><\/p>\n

A beautiful, wide open cluster near the stinger of Scorpius. While the bulk of the cluster filled the 1.4\u00b0 view, the more concentrated portion spanned about 15-20′. This concentration was bounded by a square of brighter stars. The SW corner of that square appeared to be marked by a reddish star, while a row of 6 stars spanned the E edge like a spine. As low as this was in the haze of the southern sky, it was still a striking view.<\/p>\n

Factoids:<\/b><\/p>\n

This cluster was recently named after Ptolemy who described it in 130 AD as a “nebula following the sting of Scorpius”<\/i>. M7 is an open cluster consisting of 80 stars brighter than 10th magnitude. It is 800 to 1000 light years distant, and spans 20-25 light years across. The age of the cluster is estimated at 220 million years. The whole group is approaching us at 14 km\/sec. The brightest star is a yellow giant. (Thus demonstrating my current ignorance in estimating the color of stars through the eyepiece–it looked red to me, at least in comparison to the neighboring stars.)<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
Subject<\/b><\/td>\nM7\/NGC 6475<\/td>\n<\/tr>\n
Classification<\/b><\/td>\nOpen Cluster<\/td>\n<\/tr>\n
Position<\/b><\/td>\nScorpius [RA: 17:53.9 \/ Dec: -34:49]*<\/td>\n<\/tr>\n
Size*<\/b><\/td>\n80′<\/td>\n<\/tr>\n
Brightness*<\/b><\/td>\n3.3<\/td>\n<\/tr>\n
Date\/Time<\/b><\/td>\n10\/3\/04 – 8:00 PM<\/td>\n<\/tr>\n
Observing Loc.<\/b><\/td>\nFlagstaff, AZ – Home<\/td>\n<\/tr>\n
Instrument<\/b><\/td>\nOrion SVP 6LT Reflector (150 mm dia.\/1200 mm F\/L)<\/td>\n<\/tr>\n
Eyepieces\/Mag.<\/b><\/td>\n32 mm (37X)<\/td>\n<\/tr>\n
Seeing<\/b><\/td>\n5\/10<\/td>\n<\/tr>\n
Transparency<\/b><\/td>\nMag 4.5<\/td>\n<\/tr>\n<\/table>\n

* Based on published data.<\/p>\n","protected":false},"excerpt":{"rendered":"

M007A<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[16,18,24,19,21,25,22,26,15],"tags":[],"class_list":["post-32","post","type-post","status-publish","format-standard","hentry","category-deep-sky","category-messier","category-open-cluster","category-sg-deep-sky","category-sg-messier","category-sg-open-cluster","category-sg-star-cluster","category-sgc-scorpius","category-sketch-gallery"],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":34,"url":"https:\/\/perezmedia.net\/beltofvenus\/2004\/10\/03\/m6_butterfly_cl\/","url_meta":{"origin":32,"position":0},"title":"Messier 6 – Butterfly Cluster","author":"jperez1690","date":"October 3, 2004","format":false,"excerpt":"M006A","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":49,"url":"https:\/\/perezmedia.net\/beltofvenus\/2004\/10\/15\/m80\/","url_meta":{"origin":32,"position":1},"title":"Messier 80","author":"jperez1690","date":"October 15, 2004","format":false,"excerpt":"M080","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":178,"url":"https:\/\/perezmedia.net\/beltofvenus\/2005\/09\/24\/m4\/","url_meta":{"origin":32,"position":2},"title":"Messier 4","author":"jperez1690","date":"September 24, 2005","format":false,"excerpt":"M004","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":204,"url":"https:\/\/perezmedia.net\/beltofvenus\/2005\/10\/21\/m26\/","url_meta":{"origin":32,"position":3},"title":"Messier 26","author":"jperez1690","date":"October 21, 2005","format":false,"excerpt":"M026","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":37,"url":"https:\/\/perezmedia.net\/beltofvenus\/2004\/10\/04\/m71\/","url_meta":{"origin":32,"position":4},"title":"Messier 71","author":"jperez1690","date":"October 4, 2004","format":false,"excerpt":"M071","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":45,"url":"https:\/\/perezmedia.net\/beltofvenus\/2004\/10\/14\/m55\/","url_meta":{"origin":32,"position":5},"title":"Messier 55","author":"jperez1690","date":"October 14, 2004","format":false,"excerpt":"M055","rel":"","context":"In "Deep Sky"","block_context":{"text":"Deep Sky","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/deep-sky\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/posts\/32","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/comments?post=32"}],"version-history":[{"count":0,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/posts\/32\/revisions"}],"wp:attachment":[{"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/media?parent=32"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/categories?post=32"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/tags?post=32"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}