English | Deutsch | Español | Italiano | Português |
... М100 < М101 > М102 ...

Spiral galaxy M101

Spiral galaxy M101 or Pinwheel is in the constellation Ursa Major (UMa).


Equatorial coordinates (epoch J2000):
Ra (α):14h03.2m, Dec (δ):+54° 21'

Visual magnitude: 7,7m
Distance from the galaxy M101 to the Sun is 21,8*106 light years
Angular size: 29'×27'
Class: Sc
External dimensions the galaxy M101 are about 184000 light years.

Discoverer: Pierre François André Méchain, 27.03.1781 year.

The designation M101 in other catalogs: NGC 5457

Optimum magnification for a telescope with observations of M101, depending on the aperture of the telescope (D), is about D/6-D/3. Higher magnifications of course add details, but lead to a strong drop in the brightness of the image, making it difficult to observe.

The best month for observing M101 is May. 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.

For observers in the northern latitudes:the night sky in May is no longer very dark, so try also to observe M101 in April.
Of course, in April the object is at midnight not at its highest point, whichprovides the least exposure and atmospheric distortion. 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.

Мessier 100
Мessier 102

Nikolay Kurdyapin, astro-map.com  

© Copyright 2018-2019, astro-map.com
At a reprint of materials from this site link to the astro-map.com obligatory.