W50 SNR in Aquila

This deep wide­field image with nar­row­band expos­ures shows a region of the Milky Way towards the con­stel­la­tion of Aquila centred around the super­nova rem­nant W50. Although it does­n’t exhib­it many fil­a­ments in the optic­al wavelength, it presents an exquis­ite and com­plete whole shell at radio wavelengths.

It was first dis­covered in 1958 by Gart West­er­hout and clas­si­fied as a super­nova rem­nant in 1969. The first detec­tion of asso­ci­ated optic­al fil­a­ments was in 1980 and spec­tro­scopy con­clus­ively proved they were part of W50. One explan­a­tion for its min­im­al optic­al emis­sion is dust obscur­a­tion towards this area near the Aquila Rift. The dis­tance has been estim­ated at 18,000 light years and might have an age of 20,000 years. The full radio shell spans 2x1 degrees in the sky and a phys­ic­al size of 700 light years.

One incred­ible aspect of W50 is that at its heart lies the well stud­ied microquas­ar bin­ary sys­tem SS 433. This is a bin­ary sys­tem con­sist­ing of a blue super­gi­ant star and a black hole orbit­ing each oth­er and are in the pro­cess of blast­ing out jets that have ener­gised the super­nova shell of W50. Anoth­er rarely seen phe­nom­ena is the inter­ac­tion of W50 with both the sur­round­ing inter­stel­lar medi­um and mag­net­ic fields.

Oth­er deep sky objects of interest in this field include the emis­sion neb­ula Sh2-74, the pair of open clusters NGC 6755–6 and the bright plan­et­ary neb­ula NGC 6781 near the top left corner. The round blue bubble towards the south of the image is the plan­et­ary neb­ula can­did­ate StDr 101, which was redis­covered by the ama­teur astro­nomers Xavi­er Strottner and Mar­cel Drechsler in August 2019. Was ori­gin­ally dis­covered as part of the IPHAS sur­vey and is also cata­logued as IPHASX J191003.4+032224 but was rejec­ted as a plan­et­ary neb­ula can­did­ate. You can find these objects in the annot­ated image.

[descrip­tion from Sakib Rasool]


Taka­hashi FSQ-106EDX III
Andor CG16M
Astro­don Gen2
HaOIIIR­GB 760:1140:80:80:80 min.
ROSA Remote Obser­vat­or­ies South­ern Alps
© Mar­tin Ruster­holz, Astrophotographer

Find­er Chart W50 SNR in Aquila

W50 Sky Chart - Astrophotography Martin Rusterholz

Image cre­ated by Skychart