Astronomical Images - the best from 2016/17
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Clicking on some images won't do anything, and on others might toggle you through an image sequence.
The Moon, taken in daylight at 20:23 with the Atik GP at the focal plane of the 1000mm f.l. 'scope.
To the top right of the image is the southern lump of the Mare Tranquillitatis, with the Mare Nectaris just below. The four large craters around this are (anticlockwise from the top) Theophilus, Cyrillus, Catharina (all about 100km across) and the slightly larger Fracastorius south of the Mare. So the picture is about 1.3km per pixel. To the East of this there is the wiggly line of the 427km long scrap Rupes Altai.
Further East, the firefly like thing is of course the International Space Station.
This time, (with 0.3ms exposures) the solar panel things are much more obvious. We have sheep grazing under solar panels here in Cambridgeshire - the worlds sheep are grazing under those mothers.
I thought about doing animations and image sequences for this - but in the end just merged back in the 5 frames with the ISS to a less noisy Registax6 stack of the full movie.
Jupiter is now moving into the western twilight, and spends much of its time over the houses down the street in the poor seeing.
Here it is in not bad seeing on the 1st of June.
The satellites are Io and Europa.
It is taken with the Atik GP and x2.7 barlow with a bit of extra spacing.
As this may be the last of my Jupiter images this apparition, I'll take the opportunity to witter on a bit about it.
With this setup, the barlow produces a magnification of 3.1, and the camera produces images at 0.247 arc seconds per pixel. The diffraction limited resolution of 200mm diameter scope is around 0.6 arc seconds.
It might be interesting to try a x5 barlow, but nothing beyond this.
On to the rotation of Jupiter. You can see a dark feature on the lower edge of the North Equatorial Belt which has rotated quite considerably in the 42 minutes between images. In fact. It's moving at about 1 pixel per minute.
I generally keep a single movie down to 400 frames at 15 frames per second - around 27 seconds - which equates to about half a pixels worth of rotation near the centre of the planet. Some of the grown up Jupiter imagers use software to de-rotated the planet before stacking - I don't think I need worry about this with the setup used here.
(N.B. - two minute movies are fine, the stacking software effectively does the de-rotation at this level).
Packing up the scope, I thought I may as well have a look at old Sol. Goodness me! - a little sunspot group, I haven't seen one of those for a while.
It is taken with the Atik GP at the focal plane of the 1000mmm f.l. 'scope (with suitable filtering over the telescope front end), and processed in Registax and AstroArt6. Although the original is an RGB image, this is just the red channel (because the red channel is best).
26th May
By Jove, it's the International Space Station... (click on the image to big it)
Despite the small sensor size I elected to take this with the Atik GP camera (rather than the DSLR). This allows me to drop the exposure time for each frame down to 0.5 ms. It still only runs at 15 frames per second, so only 6 frames contained the ISS.
Jupiter and its satellites are a Registax 6 processed image of the whole 400 frame movie. I then just merged back in the ISS from the 6 frames in which it was visible.
Ganymede is the satellite on the left. A rare appearance on these pages - the Galilean moon with the largest orbit, Calisto can just about be seen close to Jupiter (top left of the planet). Continuing right we get to zippy little Io, and then Europa.
The remarkably bright crater Aristarchus is to the left of this picture of the Mare Imbrium. The ray craters Copernicus and the smaller Kepler dominate the bottom of the picture. (Click on the picture to 'big' it.)
And the whole moon, with Jupiter to approximate scale....
My first images of Jupiter this apparition. ATIK GP camera, Explorer 200P with x2.7 Coma correcting Barlow, processed in Registax 6.
Click on the image to cycle through a sequence.
On the third time of asking, I at last got a picture of NGC4236 worthy of these pages.
It's a galaxy fainter than M74, so despite what I thought was better visibility, I couldn't see this one in the eyepiece either. The picture is a stack of 78 90 second frames, about two hours worth, starting at 2:42 in the morning.
The galaxy is about 11.7 million light years distant, and is part of the group containing the brighter M81 and M82 (despite being 12 degrees of arc from these two galaxies).
Time to try the lens clamp gizmo of my own design and kindly manufactured by Pete.
This allows me to use one of Pete's old M42 camera lenses (135mm f3.5) with the Starlight Xpress camera. The region round Orion's belt would be a good target I thought.
On the left is a mosaic of two pictures, each a stack of 50 40 second frames (processed in AstroArt 6), taken with the Starlight Xpress SX814C piggy backed on my smaller 'scope with the aid of the aforementioned lens clamp gizmo.
On the right there are a number of objects I picked out to try and individually process, so let's go through the list....
At the bottom of the picture is the Great Nebula in Orion (M42), this together with the smaller de Mairan's nebula (M43), looks like some badly drawn Mandelbrot set in the left picture.
Just up and to the right of this is the Running Man nebula (NGC 1977), rather spoilt by what looks like two (but is in fact three) stars which have joined forces to produce a big white patch.
Moving up, the two brightest stars in the picture, just above the centre line, are the two easternmost stars of the three that make up Orions belt. The central belt star, Alnilam, is on the right of this picture, and the easternmost star of the belt, Alnitak, is near the centre.
Just down from Alnitak, is the red glow of Hydrogen alpha emission, with the dark shadow of the Horsehead nebula cutting into it from the left. (Try googling the Horsehead nebula, and check out the infra-red images from the Hubble Space Telescope - they are amazing).
And up and to the left of Alnitak is the aptly named Flame nebula (NGC 2024).
Moving further up, near the top of the image, and left of centre, you will see a star like thing which looks like it's got a bit of a fly-away hair problem (flying down and to the left). That will be M78 (or at least the brighter bits of it).
Don't be fooled into thinking that the variation in the background sky level is anything other than the flat frames not working properly.
The angle between M42 and M78 is about 6.2 degrees. They are about 1344 and 1600 light years distant (respectively), so the distance between them is a mere 300 light years.
I had been messing around attempting to compare my new barlow lens with the old skywatcher barlow. The results were fairly inconclusive, certainly nothing that shone out and said the new barlow was worth the money. But nothing to suggest it was complete rubbish. In fact when you start using a x2 or x2.7 magnification taking 1 minute plus exposures, I'm sure the limiting factor is how well the mount is tracking.
Anyway, here's a combination of pictures of M57 using the Starlight Xpress Trius camera, with the coma correcting barlow (35 x 60second exposures) and the Canon DSLR with the skywatcher barlow (58 approx 80 second exposures at ISO 3200).
The background stars are from the DSLR, taken on a moonless, dewless, lovely night on the 29th August. You can see hints of a barred-spiral galaxy, at about the 'half past one' position halfway from M57 to the edge of the picture.
The nebula itself is from the Trius camera (hence the nice colours), but with a first quarter moon and visibility of varying quality - there were a few lighter pixels in the 'galaxy' position - but nothing that would draw your attention.
The ISS in front of the Moon and close to Jupiter.
The Sun, Moon and Jupiter.
M57 (the Ring nebula), NGC4236 (galaxy in Draco) and a wide angle shot of the nebulae in Orion.
Clicking on some images won't do anything, and on others might toggle you through an image sequence.
June 2017
1st JuneThe Moon, taken in daylight at 20:23 with the Atik GP at the focal plane of the 1000mm f.l. 'scope.
To the top right of the image is the southern lump of the Mare Tranquillitatis, with the Mare Nectaris just below. The four large craters around this are (anticlockwise from the top) Theophilus, Cyrillus, Catharina (all about 100km across) and the slightly larger Fracastorius south of the Mare. So the picture is about 1.3km per pixel. To the East of this there is the wiggly line of the 427km long scrap Rupes Altai.
Further East, the firefly like thing is of course the International Space Station.
This time, (with 0.3ms exposures) the solar panel things are much more obvious. We have sheep grazing under solar panels here in Cambridgeshire - the worlds sheep are grazing under those mothers.
I thought about doing animations and image sequences for this - but in the end just merged back in the 5 frames with the ISS to a less noisy Registax6 stack of the full movie.
Jupiter is now moving into the western twilight, and spends much of its time over the houses down the street in the poor seeing.
Here it is in not bad seeing on the 1st of June.
The satellites are Io and Europa.
It is taken with the Atik GP and x2.7 barlow with a bit of extra spacing.
As this may be the last of my Jupiter images this apparition, I'll take the opportunity to witter on a bit about it.
With this setup, the barlow produces a magnification of 3.1, and the camera produces images at 0.247 arc seconds per pixel. The diffraction limited resolution of 200mm diameter scope is around 0.6 arc seconds.
It might be interesting to try a x5 barlow, but nothing beyond this.
On to the rotation of Jupiter. You can see a dark feature on the lower edge of the North Equatorial Belt which has rotated quite considerably in the 42 minutes between images. In fact. It's moving at about 1 pixel per minute.
I generally keep a single movie down to 400 frames at 15 frames per second - around 27 seconds - which equates to about half a pixels worth of rotation near the centre of the planet. Some of the grown up Jupiter imagers use software to de-rotated the planet before stacking - I don't think I need worry about this with the setup used here.
(N.B. - two minute movies are fine, the stacking software effectively does the de-rotation at this level).
May 2017
28th MayPacking up the scope, I thought I may as well have a look at old Sol. Goodness me! - a little sunspot group, I haven't seen one of those for a while.
It is taken with the Atik GP at the focal plane of the 1000mmm f.l. 'scope (with suitable filtering over the telescope front end), and processed in Registax and AstroArt6. Although the original is an RGB image, this is just the red channel (because the red channel is best).
26th May
By Jove, it's the International Space Station... (click on the image to big it)
Despite the small sensor size I elected to take this with the Atik GP camera (rather than the DSLR). This allows me to drop the exposure time for each frame down to 0.5 ms. It still only runs at 15 frames per second, so only 6 frames contained the ISS.
Jupiter and its satellites are a Registax 6 processed image of the whole 400 frame movie. I then just merged back in the ISS from the 6 frames in which it was visible.
Ganymede is the satellite on the left. A rare appearance on these pages - the Galilean moon with the largest orbit, Calisto can just about be seen close to Jupiter (top left of the planet). Continuing right we get to zippy little Io, and then Europa.
April 2017
9th AprilThe remarkably bright crater Aristarchus is to the left of this picture of the Mare Imbrium. The ray craters Copernicus and the smaller Kepler dominate the bottom of the picture. (Click on the picture to 'big' it.)
And the whole moon, with Jupiter to approximate scale....
March 2017
26th MarchMy first images of Jupiter this apparition. ATIK GP camera, Explorer 200P with x2.7 Coma correcting Barlow, processed in Registax 6.
Click on the image to cycle through a sequence.
January 2017
5th JanuaryOn the third time of asking, I at last got a picture of NGC4236 worthy of these pages.
It's a galaxy fainter than M74, so despite what I thought was better visibility, I couldn't see this one in the eyepiece either. The picture is a stack of 78 90 second frames, about two hours worth, starting at 2:42 in the morning.
The galaxy is about 11.7 million light years distant, and is part of the group containing the brighter M81 and M82 (despite being 12 degrees of arc from these two galaxies).
November 2016
6th NovemberTime to try the lens clamp gizmo of my own design and kindly manufactured by Pete.
This allows me to use one of Pete's old M42 camera lenses (135mm f3.5) with the Starlight Xpress camera. The region round Orion's belt would be a good target I thought.
On the left is a mosaic of two pictures, each a stack of 50 40 second frames (processed in AstroArt 6), taken with the Starlight Xpress SX814C piggy backed on my smaller 'scope with the aid of the aforementioned lens clamp gizmo.
On the right there are a number of objects I picked out to try and individually process, so let's go through the list....
At the bottom of the picture is the Great Nebula in Orion (M42), this together with the smaller de Mairan's nebula (M43), looks like some badly drawn Mandelbrot set in the left picture.
Just up and to the right of this is the Running Man nebula (NGC 1977), rather spoilt by what looks like two (but is in fact three) stars which have joined forces to produce a big white patch.
Moving up, the two brightest stars in the picture, just above the centre line, are the two easternmost stars of the three that make up Orions belt. The central belt star, Alnilam, is on the right of this picture, and the easternmost star of the belt, Alnitak, is near the centre.
Just down from Alnitak, is the red glow of Hydrogen alpha emission, with the dark shadow of the Horsehead nebula cutting into it from the left. (Try googling the Horsehead nebula, and check out the infra-red images from the Hubble Space Telescope - they are amazing).
And up and to the left of Alnitak is the aptly named Flame nebula (NGC 2024).
Moving further up, near the top of the image, and left of centre, you will see a star like thing which looks like it's got a bit of a fly-away hair problem (flying down and to the left). That will be M78 (or at least the brighter bits of it).
Don't be fooled into thinking that the variation in the background sky level is anything other than the flat frames not working properly.
The angle between M42 and M78 is about 6.2 degrees. They are about 1344 and 1600 light years distant (respectively), so the distance between them is a mere 300 light years.
September 2016
10th SeptemberI had been messing around attempting to compare my new barlow lens with the old skywatcher barlow. The results were fairly inconclusive, certainly nothing that shone out and said the new barlow was worth the money. But nothing to suggest it was complete rubbish. In fact when you start using a x2 or x2.7 magnification taking 1 minute plus exposures, I'm sure the limiting factor is how well the mount is tracking.
Anyway, here's a combination of pictures of M57 using the Starlight Xpress Trius camera, with the coma correcting barlow (35 x 60second exposures) and the Canon DSLR with the skywatcher barlow (58 approx 80 second exposures at ISO 3200).
The background stars are from the DSLR, taken on a moonless, dewless, lovely night on the 29th August. You can see hints of a barred-spiral galaxy, at about the 'half past one' position halfway from M57 to the edge of the picture.
The nebula itself is from the Trius camera (hence the nice colours), but with a first quarter moon and visibility of varying quality - there were a few lighter pixels in the 'galaxy' position - but nothing that would draw your attention.
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