Sh2-155 – the Cave Nebula

Sh2-155 (also designated Sharpless 155 or S155) is a diffuse nebula in the constellation Cepheus, within a larger nebula complex containing emission, reflection, and dark nebulosity. It is widely known as the Cave Nebula. Sh2-155 is an ionized H II region with ongoing star formation activity, at an estimated distance of 2400 light-years from Earth. Sh2-155 lies at the edge of the Cepheus B cloud (part of the Cepheus molecular cloud), and is ionized by young stars from the Cep OB3 association. It has been suggested that radiation from the hot O-type star HD 217086 is compressing the region, triggering the formation of a new generation of stars. A study of the region’s young stellar objects by the Chandra X-ray Observatory and Spitzer Space Telescope shows a progression of stellar ages in front of the cloud, supporting the hypothesis of triggered star-formation!

Sh2-155, the Cave Nebula

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 185x5min LHaRGB (Ha blended with RGB)
Date: June – July 2017
Location: Southern Alps, France

 

VdB141 or the Ghost nebula

The Ghost Nebula (designated Sh2-136 and VdB 141) is a reflection nebula located in the constellation Cepheus. It lies near the cluster NGC 7023. Looking at the image, especially the cut-out, the nebula’s name is easily understood. The Ghost nebula is referred to as a globule and over 2 light-years across. There are several stars embedded, whose emissions make the nebula shine in brownish colour.

VdB141, Ghost nebula

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 146x5min LRGB
Date: June – July 2017
Location: Southern Alps, France

 

Cut-out of VdB141

 

 

Nebulas galore

The first picture is LDN1235, a dark molecular cloud in the constellation of Cepheus. Also visible are the bright blue reflection nebulae VdB149&150.
The second picture is a bi-color narrowband image in Ha and O3 of the hydrogen rich area in Cygnus. Top right is NGC6888 or Crescent nebula at a distance of 5000ly. Middle left is the very faint PN G75.5+1.7 or Soap Bubble nebula, discovered only very recently by an amateur astronomer in 2008 (not me  )

LDN1235

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 148x5min LRGB
Date: June – July 2017
Location: Southern Alps, France

NGC6888 and PN G75.5+1.7

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 126x5min Ha(R) + O3(B) + synth G
Date: June – July 2017
Location: Southern Alps, France

 

 

IC1396 in Hubble Palette

Having an observatory in a remote area with no light pollution doesn’t mean it’s dark all the time. The light of the moon can spoil the view. So that’s why sometimes I switch to narrow band imaging , using filters that block a large part of the spectrum. With S2, Ha and O3 filters I created a false color image according the so-called ‘Hubble Palette’. The object on this picture is IC1396 in the constellation of Cepheus at 2400 light years away.

The Elephant’s Trunk in IC1396

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 192x5min SII(R) + Ha(G) + OIII(B)
Date: June 2017
Location: Southern Alps, France

 

Arp188 or the Tadpole Galaxy

The Tadpole Galaxy is a disrupted barred spiral galaxy located 420 million light-years from Earth toward the northern constellation Draco. Its most dramatic feature is a massive trail of stars about 280,000 light-years long; the size of the galaxy has been attributed to a Galaxy merger with a smaller galaxy which is believed to have occurred about 100 million years ago. Because of its great distance from Earth, the apparent size is only 3.6 x 0.8 arcmins.
Click on the picture and see if you can spot the Tadpole galaxy in the wide-field view.

Arp188 or the Tadpole Galaxy

Telescope: 16″ f3.75 Dream Scope
Camera: FLI ML16803
Mount: ASA DDM85
Exposure: 65x5min L + 29x5min each for RGB
Date: May 2017
Location: Southern Alps, France

Data acquisition: Karel Teuwen and Bart Delsaert
Processing: Bart Delsaert