|
||
Intermarkets' Privacy Policy Support
Recent Entries
The Morning Report - 1/25/21 [J.J. Sefton]
Sunday Overnight Open Thread (1/24/21) Gun Thread: Tragedy on the River Edition! [Weasel] Food Thread: Fat Is Flavor...But Sometimes It Requires Moderation! (Who Knew?) First-World Problems...Part נײַן און דרײַסיק Unity, Bipartisanship, Reaching Across The Aisle, And Other Euphemisms For Losing...They All Mean Fascism Sunday Morning Book Thread 01-24-2021 EMT 1/24/21 Saturday Overnight Open Thread (1/23/21) Saturday Evening Movie Thread 01-23-2021 [TheJamesMadison] Cutting The Cord And Email Security
|
« NTSB: Early Indications Are The San Francisco Plane Crash Was Caused By Perhaps The Worst Pilot In The World |
Main
| Overnight Open Thread (7-7-2013) »
July 07, 2013
CAC's Spaced-Out Challenge: Galaxy Guide (Part 4) From the Shield to the ArrowOnwards we push through the Milky Way, in this week's edition of the Spaced Out Challenge. Finally leaving the Sagittarius-Scorpius region, we enter the realm of the small constellations Scutum, Sagitta, and Vulpecula; and one third of the Summer Triangle: Altair and Aquila the Eagle ![]() So, let's dive in, shall we? The region of the Milky Way being explored in this part of the guide is both expansive and small. Focusing on a section of sky stretching from the northern edge of Sagittarius to the southern end of Cygnus, the targets are in frustratingly small segments and (excluding Aquila) in small, faint constellations. ![]() ![]() ![]() We will begin where we left off, just above Sagittarius. Scutum, the shield The Wild Duck Cluster ![]() Mid-way between lamda Aquila and alpha Scutum you'll spot a tight concentration of stars in binoculars. With a telescope, this concentration becomes an incredible open cluster with a core of over a hundred stars. It surpasses any open cluster in beauty this side of the border of Cassiopeia and Perseus, and it's namesake is evident at even low-power. ![]() The Star Cloud Numerous dark nebulae obscure much of the stars in this region and are worth their own look, but in one “window” through the dust we spot a naked-eye bright patch of stars due west/southwest of the Wild Duck Cluster. Spanning several degrees, take the binoculars through a swarm smaller than the windows in Sagittarius but strikingly beautiful in it's own right. Aquila, the Eagle ![]() Our challenge object for the week lays within this constellation: Barnard's E (also known as the Triple Cave Nebulae). Actually two separate cataloged dark nebulae, hunting down the E, one degree west of Gamma Aquila, can help sharpen your skills in picking out further dark nebulae. Against the milky way star fields it appears as two greyish-black semi-transparent voids. ![]() Move your binoculars along from Altair to (gamma Aquila) then move again one more degree to the spot indicated. Get gamma out of your field of view just slightly, so your eyes can adjust and tease out these cold molecular amalgamations, the sites of future star birth: ![]() In the Scutum map, you'll notice several additional dark nebulae worth attempting to tease out. Sagitta, the Arrow One of the smallest constellations in the sky, it still holds at least one interesting object for amateur scopes traversing the summer Milky Way, the globular cluster in Sagitta (or is it?) ![]() From the SEDS Messier site, it's status as a globular has been rather nebulous (pardon the pun), and it holds several intriguing characteristics: For a long time, the classification of M71 as a globular cluster was uncertain, many astronomers thought it was a rather condensed open cluster, similar to M11...other criteria, as the radial velocity, and the abundance of heavier elements (metalicity) is of little help in this case: The radial velocity is poorly known, the sources differ from 80 km/sec in approach to 80 km/sec in recession, the most modern value being perhaps 23 km/sec in approach; this value is not very high and thus consistent with both types, and the metalicity is one of the highest for globulars, only M69 has higher abundances. It seems that the high metallicity is connected with a low number of RR Lyrae stars: None could be found in M71 (nor in M69)...Nevertheless, there's now some consensus that M71 is a loose globular. According to newer sources (e.g., W.E. Harris'globular cluster data file), it is 13,000 light years distant. Its denser, easily visible core is only about 5 to 6 arc minutes, while in photos it has an angular diameter of about 7', corresponding to a linear extension of only 27 light years, small for a globular cluster. In binoculars there is little to resolve but it stands out nicely with star 9 Sagitta close by. ![]() In even small telescopes, the core of this is-it-or-isn't-it globular resolves easily. ![]() Vulpecula, the Fox The Coathanger Cluster (Brocchi's) ![]() Long thought to be an actual cluster, only recently it has been determined the stars are simply a line-of-sight grouping. Still, this asterism of stars just below the head of the swan and the tail of the fox is striking in binoculars as we pass through the clouds and stars of the galaxy. The Dumbbell Nebula ![]() Planetary nebulae are one of the few deep sky objects that, with moderate aperture, appear to the eye as they do before a camera. Some even show color, such as the Blue Snowball. The Dumbbell Nebula is large and bright enough to be peaked at with binoculars: ![]() But really shows itself off through even the smallest telescopes: ![]() Faint greens can be detected with averted vision and aperture of about 6” or larger, and the white dwarf star corpse illuminating it is readily visible. A nebula filter, such as an O-III, can boost contrast in more light-polluted areas and yields finer details in dark skies. If you pick only a single object from this weeks list to hunt down, aim for the Dumbbell. You will not be disappointed. Next week, we travel to the most striking portion in the northern Milky Way, the kingdom of Cygnus the Swan. Link up to Guide Part 1: Galactic Core If you can, grab a copy of Astronomy magazine this month. For its 40th anniversary it has a go-to guide for 40 objects in Sagittarius, many discussed in previous Spaced-Out Challenges, and a great article expanding on the topic of dark nebulae. | Recent Comments
SturmToddler:
" Hey how is it that we can say "UK variant" of a d ..."
rickb223 [/s][/b][/i][/u]: "No bell bottoms! Posted by: Mine Safety Office w ..." John Durham 2 weeks : "Good morning No Dough No Votes for the McConnell ..." Jewells45: "Lady in Black, I know. I feel dirty every time I ..." J.J. Sefton: " 74 When CW2 starts, it sounds like we can count o ..." Lady in Black[/i][/b][/u]: "Trumps not going to run in '24. -- I don't b ..." Huck Follywood, Fopps News Sucks: "When CW2 starts, it sounds like we can count on Ut ..." Jewells45: "[i]Dominion Cheat Machines will expand their prese ..." rickb223 [/s][/b][/i][/u]: "So now that CNN is shown to willingly alter the vi ..." tbodie [/i] [/b] [/s] [/u]: "I'm even ok with him simply going blind. Post ..." Village Idiot's Apprentice [/s] [/b] [/i]: ""Hey how is it that we can say "UK variant" of a d ..." SturmToddler: "and yeah, this is brutal. the newest video is from ..." Recent Entries
The Morning Report - 1/25/21 [J.J. Sefton]
Sunday Overnight Open Thread (1/24/21) Gun Thread: Tragedy on the River Edition! [Weasel] Food Thread: Fat Is Flavor...But Sometimes It Requires Moderation! (Who Knew?) First-World Problems...Part נײַן און דרײַסיק Unity, Bipartisanship, Reaching Across The Aisle, And Other Euphemisms For Losing...They All Mean Fascism Sunday Morning Book Thread 01-24-2021 EMT 1/24/21 Saturday Overnight Open Thread (1/23/21) Saturday Evening Movie Thread 01-23-2021 [TheJamesMadison] Search
Polls! Polls! Polls!
Election Projection Federal Review Real Clear Politics Rasmussen Reports Gallup Zogby Sabato/Crystal Ball Frequently Asked Questions
The (Almost) Complete Paul Anka Integrity Kick
Primary Document: The Audio
Paul Anka Haiku Contest Announcement Integrity SAT's: Entrance Exam for Paul Anka's Band AllahPundit's Paul Anka 45's Collection AnkaPundit: Paul Anka Takes Over the Site for a Weekend (Continues through to Monday's postings) George Bush Slices Don Rumsfeld Like an F*ckin' Hammer Top Top Tens
Democratic Forays into Erotica New Shows On Gore's DNC/MTV Network Nicknames for Potatoes, By People Who Really Hate Potatoes Star Wars Euphemisms for Self-Abuse Signs You're at an Iraqi "Wedding Party" Signs Your Clown Has Gone Bad Signs That You, Geroge Michael, Should Probably Just Give It Up Signs of Hip-Hop Influence on John Kerry NYT Headlines Spinning Bush's Jobs Boom Things People Are More Likely to Say Than "Did You Hear What Al Franken Said Yesterday?" Signs that Paul Krugman Has Lost His Frickin' Mind All-Time Best NBA Players, According to Senator Robert Byrd Other Bad Things About the Jews, According to the Koran Signs That David Letterman Just Doesn't Care Anymore Examples of Bob Kerrey's Insufferable Racial Jackassery Signs Andy Rooney Is Going Senile Other Judgments Dick Clarke Made About Condi Rice Based on Her Appearance Collective Names for Groups of People John Kerry's Other Vietnam Super-Pets Cool Things About the XM8 Assault Rifle Media-Approved Facts About the Democrat Spy Changes to Make Christianity More "Inclusive" Secret John Kerry Senatorial Accomplishments John Edwards Campaign Excuses John Kerry Pick-Up Lines Changes Liberal Senator George Michell Will Make at Disney Torments in Dog-Hell Greatest Hitjobs
The Ace of Spades HQ Sex-for-Money Skankathon A D&D Guide to the Democratic Candidates Margaret Cho: Just Not Funny More Margaret Cho Abuse Margaret Cho: Still Not Funny Iraqi Prisoner Claims He Was Raped... By Woman Wonkette Announces "Morning Zoo" Format John Kerry's "Plan" Causes Surrender of Moqtada al-Sadr's Militia World Muslim Leaders Apologize for Nick Berg's Beheading Michael Moore Goes on Lunchtime Manhattan Death-Spree Milestone: Oliver Willis Posts 400th "Fake News Article" Referencing Britney Spears Liberal Economists Rue a "New Decade of Greed" Artificial Insouciance: Maureen Dowd's Word Processor Revolts Against Her Numbing Imbecility Intelligence Officials Eye Blogs for Tips They Done Found Us Out, Cletus: Intrepid Internet Detective Figures Out Our Master Plan Shock: Josh Marshall Almost Mentions Sarin Discovery in Iraq Leather-Clad Biker Freaks Terrorize Australian Town When Clinton Was President, Torture Was Cool What Wonkette Means When She Explains What Tina Brown Means Wonkette's Stand-Up Act Wankette HQ Gay-Rumors Du Jour Here's What's Bugging Me: Goose and Slider My Own Micah Wright Style Confession of Dishonesty Outraged "Conservatives" React to the FMA An On-Line Impression of Dennis Miller Having Sex with a Kodiak Bear The Story the Rightwing Media Refuses to Report! Our Lunch with David "Glengarry Glen Ross" Mamet The House of Love: Paul Krugman A Michael Moore Mystery (TM) The Dowd-O-Matic! Liberal Consistency and Other Myths Kepler's Laws of Liberal Media Bias John Kerry-- The Splunge! Candidate "Divisive" Politics & "Attacks on Patriotism" (very long) The Donkey ("The Raven" parody) |