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A weekly Astronomy podcast for everyone! No fancy language just interesting facts you can take any where.
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Show #39: Navigating your way through (part of) the Virgo Cluster Updated: 2007-05-10 19:19:00 Description: Carpe Noctem - Seize the Night!Image courtesy of Randy Brewer Virgo Galaxies!Here is a short list of some good Virgo Cluster reference. Each is different and I have used them all! There are literally 100s of articles written about navigating through the Virgo Cluster. My advice is find a good map and then find a route that suits you. I'm presenting only one way to attack the area but it is a way that works for me fairly consistently. Good luck! Alan M. MacRobert's "Mastering the Virgo Cluster" Sky and Telescope, May 1994 pg 42-This is the one I carry in my notebook because I love the route and the map. Steve Gottlieb's "The Virgo Mainline"-This one I carry for sharing a different approach for those who get lost at the beginning of the MacRobert's route. AtlasJan Wisniewski's Virgo Galaxy Cluster - Finder Chart Tonight we are using the WikiSky.org Atlas for our Virgo Tour Start by arc-ing from the handle of the big dipper to Arcturus and then "Speed on" or "Spike" to Spica. Once at Spica work you way up the body of the Maiden to Porrma, her throat, and then up her outstretched arm to Vindemiatrix. Another way is to start from the head of Leo the Lion wander west to Denebola and then across to Vindemiatrx. 46 Galaxies?!?!? Okay, here we go.... North is up Object Magnitude Type Notes Section 1 The 'on ramp'..... Epsilon Virginis - Vindemiatrix 2.8 Yellow giant 100 light yrs away Bunsen Burner 9 and 10th This asterism point away from Epsilon and in the direction we want to go Struve 1689 7 and 9.5 29" apart. NGC 4762 and NGC 4754 10.3 and 10.5 Sp 4754 is off by itself and 4762 is between a 9th and 10th mag star. Use averted vision or tap the scope to get 4762 to pop out NGC 4694 11.4 Sp Very hard to find 11.4 mag elongated NW-SE NGC 4660 11.8 E Tiny round cotton ball M60 8.8 E One of the biggest and brightest ellipticals in tonight's tour. At higher powers you can make out a slight halo as well as the companion galaxy 4647 NGC 4647 11.3 Sp Close companion to M60, 3' to the NW a challenge to pick up unless you use averted vision. It is a spiral but looks much more like a smaller version of its elliptical companion M59 9.6 E Has a profile more like a spiral but this evening is all about being faint so- 0.4deg W not as bright as M60. Giant elliptical slightly elongated SE-NW NGC 4638 11.2 Sp Fainter and smaller depending upon your field of view (FOV) you can squeeze it in along with M60 and M59 making an isosceles triangle with the three. NGC 4606 11.8 Sp A toughie. Look for a fuzzy star with two stars on the south. If you have a larger scope you may have passed over 13.0mag 4607 an edge on spiral galaxy out of reach of our smaller scopes. North is up Object Magnitude Type Notes Section 2 The first 'fork in the road'.... M58 13.0 Sp Spiral galaxy a little fainter and smaller than M59 a dark sky and larger scope (bigger than 8") will start to pick out its smoke like wisps of spiral arm. Take a good look at where you are because we will need to return back to M58 after a detour down the M90 (and friends)side alley. NGC 4550 and NGC 4551 11.7 and 12.0 Sp and E (Misprint in the MacRobert's narrative where they are referred to as 4450 and 4451) Heading NW from M58 these two sit very close together and are both very faint and tricky to find. M89 9.8 E A nice break from hunting around for the last two. It will seem to pop into view...strange how perspective does that to you. A round fuzzy blob with a brighter core. M90 9.5 Sp Just after M89 is a little "W" that runs to the NNW to M90 a giant spiral galaxy with a low surface brightness but it is very large. There is an unrelated 12 mag star sitting between the Earth and the center of this galaxy. Elongated N-S look for a darkened lane on the eastern edge. NGC 4564 11.1 Backtrack to M58 and then 0.5 deg SW to a tall box asterism just off the NE corner is 4564. NGC 4567 and 4568 11.3 and 10.8 Sp Another pair of spirals that seem to be joined at the ends. They are nicknamed the "Siamese Twins" (Who am I to argue but they reminded me much more of amoeba from high school biology class) NGC 4528 12.1 Sp Very tiny and quite faint another candidate for power, aperture and dark conditions NGC 4503 11.1 Sp Off by itself and very diffuse on 10" or smaller scopes this might take DARK skies, tapping, averted vision...all of your faint fuzzy objects tricks. North is up Section 3 Back way in.... NGC 4452 12.0 Sp This galaxy is a tiny little fuzzy. It is in between two rows of stars and there is a third row of stars below it housing... NGC 4429 10.0 Sp An easier find, still a fuzzy blob but easier than 4452 NGC 4440 11.7 Sp Slid back up to 4452 and then to the NW corner of the three rows (or Arcs) of stars. It sits just SW of the Northern most star in the arc M87 8.6 E Now we begin to appreciate the "Ms" in front of numbers. After so many faint NGC an "M" gives us hope for something bigger and brighter. Not to disappoint M87 is .75 deg East of 4440 and a nice big bright giant elliptical. The bright nucleus is one of the brightest radio sources in the sky. NGC 4478 11.4 E Is M87's companion much fainter and again needing your faint object tricks NGC 4476 12.2 Sp Here we go getting super faint again, another target for larger scopes or darker skies (or sometime more experience) but give it your best because your rewards is... North is up Section 4 "The Grand Tour" or "Markarian's Chain" M84-M86 9.1 and 8.9 E We start with the 'face' of the Chain M84 and M86, both elliptical galaxies, make up the eyes of the face. M86 is distinctly brighter with its own little cluster on the NE corner. NGC 4388 and 4387 11.0 and 12.1 Sp and E Making an equilateral triangle to the South and forming the mouth is NGC 4388 and edge on E-W spiral galaxy and directly in the middle of the triangle finishing off the nose is NGC 4387 another elliptical galaxy. NGC 4402 11.8 If the face had an eyebrow then it would be 4402. North 8.5ish' from M86 the E-W edge on spiral galaxy appears to have a slight dust lane and a North leaning bulge. Almost like a ladies broad brim hat. NGC 4413 12.2 Sp In the opposite direction 9'WSW of 4388, NGC 4413 is an almost face on spiral galaxy NGC 4425 11.8 Sp From 4388 make and equilateral triangle to the west with M86 and your corner will be roughly in the area of 4425 another edge on spiral galaxy brighter than 4413 Now we can start moving up the Chain in pairs... NGC 4435 and 4438 10.8 and 10.2 Sp Draw a line WNW from M84 and M86 to the first pair in the chain, both spiral galaxies. Nick-named "The Eyes" 4438 is slightly longer with wispy arms reaching NW-SE and both galaxies mirror each other in orientation NW-SE NGC 4461 and 4458 11.2 and 12.1 Sp and E The next pair, fainter the elliptical 4458 is all but indistinguishable (for me)from the small 10.95 mag star to its NW. 4461 is slightly brighter spiral galaxy elongated N-S NGC 4473 10.2 E This slightly brighter elliptical lost her buddy (bad Scout) and lays E-W alone in the middle of the Chain. You may not have noticed but you are now in Coma Berenices. NGC 4477 and 4479 10.4 and 12.4 Sp About 12' NNW are another pair of spiral galaxies. 4477 is the brighter and Eastern most of the pair NGC 4459 and 4474 10.4 and 11.5 Sp A wider pair of spirals 4459 is very close to a 8.2 yellow star and look like an elliptical galaxy. 4474 is much fainter but has that familiar central bulge of an edge on galaxy. M88 9.6 Sp The last two links in the Chain are biggies and brighties! M88 is a partial face on spiral with a multitude of arms making a nice even frisbe disk. M91 10.2 Sp A particularly appropriate reward at the end. This face on barred spiral is beautiful with two large arms sweeping out on opposite sides. SunCurrent view of the Sun! Comets Comets for the Month.Check out the Sky Hound site. Music"Wake the Dragon" by Dragon Ritual Drummers"Over Again" by Rebecca Loebe "One touch of nature makes the whole world kin"-- Shakespeare Email us at astronomyagogo@gmail.com or leave a note in our show notes at www.astronomy.libsyn.comHelp us out by leaving a donation in the ol' PayPal hat Woodland Hills Camera and Telescope is offering FREE web hosting on our servers for you or your organization's website. In order to promote the hobbies of Astronomy, Astrophotography, Photography, Birding or generally any topic that is of interest to our customer base, Woodland Hills Camera and Telescope is offering Hosting Grants. LISTEN NOW | DOWNLOAD |
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