June 2018

This is the quietest month for deep sky astronomy;  the days either side of the Summer solstice are long and truly dark nights are a distant memory, especially for those living in the North of the British Isles.

Nevertheless two section members sent in their images;  a total of four in all.

David Davies of Cambridge used an 8″ Richey Chretien telescope and QSI 583 mono cameras plus red, green and blue filters to image globular cluster M3, which lies in the constellation of Canes Venatici.

M3

M3 is considered to host about 500,000 stars and more variable stars than any other globular cluster.  It is around 35,000 light years from the Earth and at magnitude 6.2 may be seen with binoculars.

 

Steve Norrie, who observes from Fife, sent in three images which he had taken earlier in the year but only recently processed.  The first image is of Sh2-155, the Cave emission nebula, in the constellation of Cepheus.

Sh2-155

This emission nebula is also known as Caldwell 9:  bright, hot O and B stars are ionising the surrounding  gas with copious amounts of ultra violet radiation.  It is thought that one of these stars in particular, HD 217086, is helping new star formation by compressing the gas and dust around it.  Steve used an ES 127mm f7.5 APO refractor plus a StarlightXpress Trius 694 mono camera and narrow band filters to render this image in the Hubble palette.

The second and third images are both of emission nebula IC 410, the Tadpoles nebula in the constellation of Auriga;  one using narrow band filters as with Sh-2 155 and the other using red, blue and green filters plus the same telescope as above.

IC 410
IC 410 (RGB)

The RGB image shows best the 4 million year old open cluster NGC 1893 whose stars are providing the ionising radiation.  The Tadpoles at the bottom of the nebulosity in these images are regions of star birth similar to the iconic Hubble telescope “pillars of creation” image.

Dave Finnigan