The first to note the spiral structure of the Whirlpool Galaxy was the wealthy Irish amateur astronomer Lord Rosse. Keen-eyed observers can see spiral structure in smaller scopes in dry and very dark sky. But in dark sky, with a careful gaze and averted vision, the galaxy is transformed into a glorious– if faint– spiral swirl in an 8″ or larger telescope. Urban stargazers often look to M51, see a couple of dim smudges, and wonder what all the fuss is about. In a 3-inch telescope or larger, the core of NGC 5195 is also visible. In light-polluted skies, you will only see the core, no matter how big your telescope, because the fainter spiral arms are overwhelmed by the artificially brightened sky. It’s the core you can see in a pair of binoculars or a telescope. An 1845 sketch by Lord Rosse of the galaxies M51 and NGC 5195.Īs with most spirals, the core of M51 outshines the fainter spiral arms. Images also show a bridge of stars that appears to connect the two galaxies. In images of the galaxy, you can see evidence of this activity in the numerous pink emission nebulae and blue-white clots of new stars (see above). And it’s not alone: the galaxy interacts with its much smaller neighbor NGC 5195, and the interaction has triggered an intense round of star formation, especially in the rich spiral arms of M51. This elegant face-on spiral spans about 1/3 the diameter of our own galaxy and lies at a distance of about 23 million light years. This showpiece object is just 3º southwest of the star Alkaid. Let’s begin with the most famous galaxy around Dipper’s handle, the Whirlpool Galaxy, which lies over the border in the constellation Canes Venatici (the Hunting Dogs). In dark skies, these two nearby galaxies display clear hints of a striking and ubiquitous pinwheel shape that reveals itself in the clouds of a hurricane or the seed arrangement in a sunflower, a reminder that many of nature’s patterns appear at a wide range of scales. The handle of the Dipper offers a convenient guide two stately face-on spiral galaxies that are visible, at least to some degree, in a small telescope. But, the darkness of the April sky greatly increases the contrast.The farther south the location of your observation is located, the darker the summer sky will be.Messier 51, the Whirlpool Galaxy, and its companion NGC 5195. Of course, in April the object is at midnight not at its highest point, whichprovides the least exposure and atmospheric distortion. At this time, the object is at midnight near its highest point in the sky, that is, it is less affected by light from the lanterns and atmospheric distortions.įor observers in the northern latitudes:the night sky in May is no longer very dark, so try also to observe M51 in April. Higher magnifications of course add details, but lead to a strong drop in the brightness of the image, making it difficult to observe. Optimum magnification for a telescope with observations of M51, depending on the aperture of the telescope (D), is about D/6-D/2. The designation M51 in other catalogs: NGC 5194,NGC 5195 Spiral galaxy M51 or Whirlpool is in the constellation Canes Venatici (CVn).ĭistance from the galaxy M51 to the Sun is 26,8*10 6 light yearsĮxternal dimensions the galaxy M51 are about 87000 light years.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |