{"id":345,"date":"2007-07-15T04:12:54","date_gmt":"2007-07-15T04:12:54","guid":{"rendered":"http:\/\/perezmedia.net\/beltofvenus\/2007\/07\/15\/alpha_scorpii_a\/"},"modified":"2021-11-28T00:27:31","modified_gmt":"2021-11-28T00:27:31","slug":"alpha_scorpii_a","status":"publish","type":"post","link":"https:\/\/perezmedia.net\/beltofvenus\/2007\/07\/15\/alpha_scorpii_a\/","title":{"rendered":"Alpha Scorpii (Antares \/ GNT 1)"},"content":{"rendered":"

<\/a>
\nClick image for larger version.<\/i><\/p>\n

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

The goal of splitting the double star, Antares, has been tempting me for a while. I never have the sort of seeing conditions that would make it a nice clean observation. So I gave it a try on this less-than-perfect evening, and was successful in spotting the secondary star. Antares’ primary star flickered like a coppery flame in the jumping air currents, so I had to be patient and wait for the ripples of diffracted light to show me the way. The secondary began to coalesce as a consistent lump in the fluttering kidney beans of orange light near the position of the primary star’s second diffraction ring. It’s color was hard to pick up, but gradually, I perceived what looked like a yellow-green tint. I had not checked data on the secondary’s current position angle to help keep me honest, and it looked to be at a PA of about 280 degrees. Checking Brian Workman’s double star calculator a couple days later gave a PA of 277\u00c2\u00b0 for 2007.5. The separation comes out to 2.18 arcseconds, which is about right for my ‘second diffraction ring’ sighting–that works out to 2.5 arcseconds in my scope.<\/p>\n

I wanted to convey what the diffraction pattern looked like, and how the secondary appeared in the midst of it. The digital sketch I prepared was a bit of a learning experience for me, but I think it does a halfway decent job of rendering what I saw. This can be seen in the detail portion of the sketch. Just imagine all of that jumping around and moving from moment to moment. Clicking the sketch will provide a larger image that is easier to see. You’ll notice that I was fortunate enough to have the spider vanes in a position that didn’t interfere with the secondary star. It really was a beautiful and challenging sight. Give it a try sometime and see if you can identify the secondary in that bubbling mass of starlight.<\/p>\n

I’d love to see what they look like under near-perfect seeing.<\/p>\n

[Edit June 8, 2012]: Updated digital sketch to match current double star style.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Subject<\/b><\/td>\nAlpha Scorpii (Antares \/ GNT 1)<\/b><\/td>\n<\/tr>\n
Classification<\/b><\/td>\nDouble Star<\/td>\n<\/tr>\n
Position (J2000)<\/b><\/td>\nScorpius [RA: 16:29:24.4 \/ Dec: -26:25:55]*<\/td>\n<\/tr>\n
Position Angle*<\/b><\/td>\n277\u00c2\u00b0 (2007.5)<\/td>\n<\/tr>\n
Separation*<\/b><\/td>\n2.18″ (2007.5)<\/td>\n<\/tr>\n
Magnitudes*<\/b><\/td>\n0.96 \/ 5.4<\/td>\n<\/tr>\n
Spectral Types*<\/b><\/td>\nM1.5 IB E \/ B2.5V<\/td>\n<\/tr>\n
Date\/Time<\/b><\/td>\nMAY 11, 2007 – 11:35 PM MST (MAY 12, 2007 – 06:35 UT)<\/td>\n<\/tr>\n
Observing Loc.<\/b><\/td>\nAnderson Mesa, AZ<\/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>\n10 mm + 2X Barlow (240X)<\/td>\n<\/tr>\n
Conditions<\/b><\/td>\nMostly clear, calm<\/td>\n<\/tr>\n
Seeing<\/b><\/td>\n5-6\/10 Pickering<\/td>\n<\/tr>\n
Transparency<\/b><\/td>\nNELM Mag ~6.0<\/td>\n<\/tr>\n
References<\/b><\/td>\nThe Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); 12th General Catalogue of MK Spectral Classification (Buscombe+ 1995); Brian Workman’s Double Star Calculator<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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

Alpha Scorpii<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[56,57,26,15],"tags":[],"class_list":["post-345","post","type-post","status-publish","format-standard","hentry","category-double-star","category-sg-double-star","category-sgc-scorpius","category-sketch-gallery"],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":510,"url":"https:\/\/perezmedia.net\/beltofvenus\/2009\/12\/05\/xi_scorpius_str\/","url_meta":{"origin":345,"position":0},"title":"Xi Scorpii (Struve 1998) and Struve 1999","author":"jperez1690","date":"December 5, 2009","format":false,"excerpt":"Xi Scorpii","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":308,"url":"https:\/\/perezmedia.net\/beltofvenus\/2006\/12\/10\/conjunction_of\/","url_meta":{"origin":345,"position":1},"title":"Conjunction of Mercury, Mars, Jupiter, and Beta Scorpii","author":"jperez1690","date":"December 10, 2006","format":false,"excerpt":"Conjunction of Mercury, Mars, Jupiter, and Beta Scorpii","rel":"","context":"In "Planetary"","block_context":{"text":"Planetary","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/planetary\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":14,"url":"https:\/\/perezmedia.net\/beltofvenus\/2004\/08\/01\/double_star_ske\/","url_meta":{"origin":345,"position":2},"title":"Double Star Sketches","author":"jperez1690","date":"August 1, 2004","format":false,"excerpt":"Double Star Sketches","rel":"","context":"In "General"","block_context":{"text":"General","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":427,"url":"https:\/\/perezmedia.net\/beltofvenus\/2008\/08\/16\/the_false_comet\/","url_meta":{"origin":345,"position":3},"title":"The False Comet (NGC 6231 & CR 316) and NGC 6242","author":"jperez1690","date":"August 16, 2008","format":false,"excerpt":"NGC 6231","rel":"","context":"In "Asterism"","block_context":{"text":"Asterism","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/asterism\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":237,"url":"https:\/\/perezmedia.net\/beltofvenus\/2006\/02\/25\/ophiuchus_sagit\/","url_meta":{"origin":345,"position":4},"title":"Ophiuchus, Sagittarius, Scorpius Milky Way","author":"jperez1690","date":"February 25, 2006","format":false,"excerpt":"Ophiuchus, Sagittarius, Scorpius Milky Way","rel":"","context":"In "Constellation"","block_context":{"text":"Constellation","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/constellation\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":273,"url":"https:\/\/perezmedia.net\/beltofvenus\/2006\/09\/03\/alpha_librae\/","url_meta":{"origin":345,"position":5},"title":"Alpha Librae (SHJ 186)","author":"jperez1690","date":"September 3, 2006","format":false,"excerpt":"Alpha Librae","rel":"","context":"In "Double Star"","block_context":{"text":"Double Star","link":"https:\/\/perezmedia.net\/beltofvenus\/category\/double-star\/"},"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\/345","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=345"}],"version-history":[{"count":2,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/posts\/345\/revisions"}],"predecessor-version":[{"id":842,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/posts\/345\/revisions\/842"}],"wp:attachment":[{"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/media?parent=345"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/categories?post=345"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/perezmedia.net\/beltofvenus\/wp-json\/wp\/v2\/tags?post=345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}