The Milky Way: July-August

  • Michael D. Inglis
Part of the Patrick Moore’s Practical Astronomy Series book series (PATRICKMOORE)


Let me state now that there are those amateur astronomers who believe this part of the Milky Way is the most spectacular, and who am I to disagree2 Star Chart 2.1 The star clouds of Sagittarius are justifiably some of the most wonderful and awe-inspiring regions that can be observed (see Figure 2.1). But before you grab hold of your binoculars and make a mad dash outside, there is of course another side to this. For those lucky observers who live in, say, southern Europe or the southern United States, and those who are very fortunate to live in equatorial regions, then these skies will provide views and scenes you are unlikely to ever forget. Those of us, however, who live in northern Europe and Canada have to deal with the unfortunate fact of life that Sagittarius will always lie close to the horizon, and sometimes when we read about the amazing sights that await observers in this region of the sky and then try to see them we are often left with a sense of disappointment. The only advice I can offer is this: these regions are truly spectacular, so try to observe with an unobstructed horizon, and with dark skies. If this is not possible, book a holiday to a location where the skies are clear and Sagittarius is at the zenith, You will never forget it!3


Open Cluster Globular Cluster Variable Star Large Aperture Central Star 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    See Appendix 1 for details on astronomical coordinate systems.Google Scholar
  2. 2.
    Well, actually, I think the Milky Way in Cygnus along with its mysterious Great Rift is equally wonderful.Google Scholar
  3. 3.
    I was once fortunate enough to observe from the depths of Turkey where the sky was unbelievable. I was able to see many objects in the Milky Way, with the naked eye, that I had only ever read about. The moral of this tale is simple — dark skies are crucial to observing faint objects!Google Scholar
  4. 4.
    Bear in mind that the center isn’t actually located in space in Sagittarius. It is just that when we look at the constellation we are looking towards the area where the center is located.Google Scholar
  5. 5.
    It is estimated that the light is dimmed by about 27 to 28 magnitudes. This is a diminution of around 60 billion. That’s a lot!Google Scholar
  6. 6.
    Sagittarius A* is now believed to be made of two components; SgrA East and SgrA West. The former is a supernova remnant, and the latter is an ultra compact, nonthermal source, i.e., a black hole.Google Scholar
  7. 7.
    Recent analysis suggests that the density around the center of the Galaxy is about a million times greater than any known star cluster. It is probably made up of stars, dead stars, gas and dust, and of course a black hole.Google Scholar
  8. 8.
    There are of course a few old stars and open clusters.Google Scholar
  9. 9.
    It is also referred to as the Little Star Cloud in some books.Google Scholar
  10. 10.
    The colorful nebulae that populate the pages of popular astronomy magazines and books do not often resemble anything that can be seen at an eyepiece. The reason is that the eye doesn’t handle color too well at low light levels. Do not be disappointed, then, when after having seen the multicolored textures of, say, the Trifid Nebula, the real thing only shows a pale grey or perhaps bluish tint.Google Scholar
  11. 11.
    I was never able to see this object with the naked eye from the UK, but it is an easy object from most parts of the USA, and it really is spectacular.Google Scholar
  12. 12.
    Towards the northern aspect of the constellation there is a particularly dark dust cloud near the open cluster IC 4756 (see later) that blots out the light from the Milky Way.Google Scholar
  13. 13.
    A prime example of astronomical imagery fooling the amateur into thinking that these justifiably impressive objects can easily be seen through a telescope.Google Scholar
  14. 14.
    Other examples of this class of variable star are Rho (p) Puppis and Beta (β) Cassiopeiae.Google Scholar
  15. 15.
    The easternmost regions of the constellation are not actually within the Milky Way, and in older star atlases only the central region is located within it.Google Scholar
  16. 16.
    There is in fact a very faint 13.7 magnitude star some 12 arcseconds away that will make the system a triple star system, but it is only visible in large telescopes.Google Scholar
  17. 17.
    Other clusters in Aquila that are cataloged as nonexistent are NGC 6828, 6837, 6840, 6843 and 6858.Google Scholar
  18. 18.
    They are not really odd, just examples of stars that are relatively rare.Google Scholar
  19. 19.
    The coordinates for NGC 6879 as listed in the RNGC catalogue appear to be in error, as there is no cluster there. It is more likely that the cluster is the one that is close to Theta Sagittae.Google Scholar
  20. 20.
    It appeared that M 71 had more metals than was normal for a globular cluster and lacked the RR Lyrae type stars that are so typical for globulars. This has been explained by its relative youth-the stars have not evolved to the RR Lyrae stage of star evolution.Google Scholar
  21. 21.
    Recent work suggests that it may not be a cluster at all, but rather an asterism.Google Scholar
  22. 22.
    Actually, it is worth observing at any time when conditions permit.Google Scholar
  23. 23.
    Eccentricity is just a measure of how circular the orbit is.Google Scholar
  24. 24.
    A more recent name is “wind-blown Wolf-Rayet ring nebula”.Google Scholar

Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Michael D. Inglis
    • 1
  1. 1.FRASState University of New YorkUSA

Personalised recommendations