Left Navigation

3towers Observatory Moon Halos

 

Moon Halo around the 3 Radio Towers

One of the 3 radio towers silhouetted by the Moon and surrounded by a Moon Halo.  This picture was taken on a misty foggy evening. 17 mm f/4.5 lens, 30 second exposure, Ektachrome 200 film.  

 

Tucson usually has very warm dry days and nights, but there are occasional nights when it is overcast or even misty without actually raining.  Sometimes, on these evenings a ring or halo can be seen around the Moon.  It is a wonderful sight and not that infrequent.  There are many Moon halos during the year.  A similar halo can be seen around the Sun on an occasional cloudy day.   

These halos occur when high thin clouds containing tiny ice crystals cover much of the sky.  Each of these crystals acts like a tiny lens, and many of the crystals have a similar elongated hexagonal shape.  As a result, each crystal bends the Moon’s light in a similar direction giving a 22 degree ring of light around the Moon. The inner edge of the halo has a red color while most of the halo is whitish. The most common form of high-level clouds are wispy cirrus clouds which are typically found at heights of 20,000 feet or higher.  Cirrus clouds are composed of ice crystals from freezing of water droplets.  Exactly how the crystals form is not fully understood.  These crystals are about 20 microns in diameter, so small that 50 of them side by side would only measure 1 mm. 

 

Moon Halos: 2005 - 2015

 

Moon Halo 23 November 2005. 8 mm f/4 lens and 16 mm f/4 lens, respectively, 5-second exposures with Nikon D100 digital camera, ISO 800.

Moon halo November 23, 2005

Moon halo November 23, 2005

Moon Halo 7 February 2006. Notice the relatively thin clouds and the stars visible through the clouds. Orion is evident to the South (bottom) and Taurus and the Pleiades are visible to the East (right).

Inside the halo North of the Moon is Auriga, and Perseus is visible in the upper right hand corner.

Ten second exposure with Nikon D100 digital camera at ISO 800, 16 mm f/4 lens.

Moon halo February 7, 2006

Moon Halo 7 February 2006. The exposure is centered South of the halo to show Orion and Canis Major. Note the light pollution of Tucson to the South. Ten-second exposure with Nikon D100 digital camera at ISO 800, 16 mm f/4 lens.

Moon halo February 7, 2006

 

Moon Halo 26 March 2007.  Eight-second exposure with Nikon D100 digital camera at ISO 800, 8 mm f/4 lens.

Moon halo March 26, 2007

 

Moon Halo 6 April 2007.  Eight-second exposure with Nikon D100 digital camera at ISO 800, 8 mm f/4 lens.  Jupiter lies in part of the Halo.

Moon halo April 6, 2007

Moon Halo 28 September 2007. Eight second exposure with Nikon D100 digital camera at ISO 800, 16 mm f/4 lens.

Moon halo September 28, 2007

Moon Halo and Mars November 26, 2007.  Eight-second exposure with Nikon D100 digital camera at ISO 800, 8 mm f/4 lens.  Mars lies in part of the Halo.

Moon halo and Mars on November 26, 2007

Moon Halo and Mars November 28, 2007.  Eight-second exposure with Nikon D100 digital camera at ISO 800, 8 mm f/4 lens.  Mars lies in part of the Halo.

Moon halo and Mars on November 28, 2007

Moon Halo on February 5, 2009. Four-second exposure with 8 mm f/4 lens on a Nikon D100 camera, ISO 800.

Moon halo February 5, 2009

Moon Halo on February 5, 2009. Four-second exposure with 16 mm f/4 lens on a Nikon D100 camera, ISO 800.

Moon halo February 5, 2009

Moon Halo on February 6, 2009. Four-second exposure with 8 mm f/4 lens on a Nikon D100 camera, ISO 800.

Moon halo Februray 6, 2009

Moon Halo on December 27, 2009. Four-second exposure with 8 mm f/4 lens on Nikon D100 camera, ISO 800.

Moon halo December 27, 2009

Moon Halo on December 28, 2009. Four-second exposure with 8 mm f/4 lens on Nikon D100 camera, ISO 800.

Moon halo December 28, 2009

Moon Halo on January 29, 2010. Eight-second exposure with 8 mm f/4 lens on Nikon D100 camera, ISO 800.

Moon halo January 29, 2010

 

Moon Halo on February 26, 2010.  Ten-second exposure with 8 mm f/4 lens on Nikon D100 camera, ISO 800.

Moon halo February 26, 2010

 

Moon Halo on November 24, 2010.  Four second exposures with 8 mm f/4 and 16 mm f/4 lenses, respectively, on a Nikon D100 camera, ISO 800.

Moon halo November 24, 2010

Moon halo November 24, 2010

Wide angle view of the Total Eclipse of the Moon on the morning of December 21, 2010.  Image taken at mid-totality.  Ten second exposure with 8 mm f/4 lens on Nikon D100 camera.

Moon Halo on December 21, 2010, the evening after the Total Eclipse of the Moon (same day).  Four and 8 second exposures with 8 mm f/4 lens on Nikon D100 camera.

Lunar Eclips - midtotality - December 21, 2010

Moon halo December 21, 2010

Moon halo December 21, 2010

Moon Halo on the evening of March 29, 2015. Four second exposure with 8 mm f/4 lens on Nikon D100 camera set at ISO 800. On the second image several bright objects have been labelled.

Moon Halo March 29, 2015

Moon Halo March 29, 2015

Moon Halo on the evening of December 21, 2015 (Winter Solstice!). Four second exposure with 8 mm f/4 lens on Nikon D100 camera set at ISO 800. Moon Halo December 21, 2015
Moon Halo on the evening of January 18, 2016. Four second exposure with 8 mm f/4 lens on Nikon D100 camera set at ISO 800. Moon Halo January 18, 2016
Moon Halo on the evening of January 19, 2016. Four second exposure with 8 mm f/4 lens on Nikon D100 camera set at ISO 800. Moon Halo January 19, 2016
   
Back to top |Lunar Web Cam Imaging |Lunar Features | Lunar 100 | Lunar Eclipses