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

About Me

Hello, my name is Martin Rusterholz. I’m a Swiss amateur astrophotographer living near Zurich, the biggest town in Switzerland. My interest in astronomy started when I was 16. At that time, I built my first Newtonian telescope and mount. I studied physics at the Swiss Federal Institute of Technology (ETH) which was the only study including at least some aspects of astronomy and astrophysics. “Looking at the nights sky is an experience touching everybody deeply inside, something common to all human beings independent to the language spoken by the individuals”. Deep-sky astrophotography is my passion.