The year moves on, and so does the night sky. In the Northern Hemisphere, summer's deep sky objects start to make an appearance in the late evenings -- favourite tantalizing stars such as Vega in Lyra and Arcturus in Boötes make a return from the east, and with them some remarkable Messier deep sky objects. A merge of hours' observing in late April revealed some real stunners, along with M13, and M92. Much lower down, I should have been able to see M3 in the constellation Canes Venatici, and M57 (the Ring Nebula) in the constellation of Lyra, but pretty bad light pollution from local business towards my eastern horizon severely restricts observing low down deep sky objects with low exterior brightness, such as planetary nebulae, galaxies and star clusters.
I all the time tend to use a 26mm or 20mm eyepiece initially when viewing deep sky objects, following successfully lining them up in my finderscope. Sometimes, as in the case of M81 (Bode's Nebula) and M82 (the Cigar Galaxy) in Ursa Major, the smaller eyepiece and wider angular field of view allows for some tantalizing framings of deep sky objects together. When it is time for closer inspection, I increase the magnification with my x2 Celestron Barlow lens. In my location, with moderate light pollution and no filter, most deep sky objects, being so faint, of course don't bear greater magnification with a 200mm cleft reflector, except of course, tantalizing star clusters and objects such as M42, the Orion Nebula.
Telescope
So what my bagging of these two superb globular clusters, both of which looked remarkable at x80 magnification? Both are globular clusters. M92 alternatively known as Ngc 6341 was discovered in 1777 by Johann Elert Bode, and has an apparent magnitude of +6.4 making it one of the more conspicuous globular clusters. Charles Messier independently rediscovered it and catalogued it on March 18, 1781. It lies 26,700 light years distant in our galaxy's halo, like M13 in the constellation of Hercules.
M92 is descriptive to the naked eye under very good conditions and a showpiece through whether a telescope or binoculars. It has a mass of almost 330,000 suns, and has an angular size of 14 arc minutes, astonishingly it is windup in on the central regions of the Milky Way at a staggeringt 112 km/sec!
So much or M92, what about the superb 'Great globular heap in Hercules', otherwise known as M13 or Ngc6205? It's at a similar distance of about 25,100 light years, has an apparent magnitude of +5.8, and has an angular size of 20 arc minutes. It was discovered by Edmond Halley in 1714, and is one of the best known globulars in the of the Northern celestial hemisphere. M13 contains any 100,000 stars, and in 1974 was a target for one of the first radio messages addressed to possible extra-terrestrial tantalizing races, sent by the large radio telescope at Arecibo.
Both M13 and M92 are gems in the northern night sky, and summer's the time to start making the most of them!
Superb Northern Summer Deep Sky Objects Move in From the East!Recommend : Know Memorial Camera Lens
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