Ewelme Observatory
This page is intended to discuss aspects of astronomy with respect to this particular location. Although some content has been around for sometime now, it has only been recently (2012) that an observatory dome has been installed here. The aim is to automate the internal reflecting telescope and associated controls remotely. It will always be under review when I've managed to discover another fact or achieved a photograph of something interesting. An ambition is to obtain some sort of image of each of the major planets, and a few 'deep sky' objects from what's called the Messier catalogue. However, this may take some considerable time! One immediate general use of this section is as a means of identifying the current position of the planets, including the Moon and the Sun, calculated from our garden in EWELME (Lat: 51.623 N, Long: 1.077 W)
Watch this 'space' for more information about the heavens. In the meantime, I wish you "Clear Skies!".
Position of the
Planets 1 &
Position of the
Planets 2
These pages display the result of a complex set of real time
calculations, showing the position of the objects within the
solar system at a given moment in time. It has been written in
JavaScript, which is software your browser can interpret
if
enabled.
Venus
Illustrates the 'Transit of Venus', a rare event where the
planet Venus passes across the face of the sun.
Jupiter
Some images of this planet and its moons.
Saturn
Video and pictures of this iconic astronomical object.
Sun
Images of the nearest star, using special filters to
see sun spots and prominences.
Moon
Images taken through my telescope to highlight the craterous
moonscape of our nearest neighbour.
Comets
2013 could prove to be a good year for comets. This
page reserved for any captured images.
Telescopes
This section discusses the type of telescopes I have, and
relates a software development project to control and XY stepper
motor system to produce a 'GoTo' telescope.
Astronomical
Distance and Time
Illustrations of how the vast distances of astronomical objects
can be related to looking back in time
Draft Gallery
This section provides an overview of recently acquired
images, yet to be finally processed or itemised. Unless stated,
these were acquired using a SkyWatcher 8" Newtonion Telescope
and Canon 750 DSLR camera, with Orion guide camera.
Click on the thumbnails to display a higher resolution image.
The field of view of each image is the same, equivalent to about
2 x full moons. Zoom in to see more detail.
Orion Nebula M42
An iconic astro image found just below 'Orion's Belt', but
requiring some post processing to highlight both the central
'trapezium' stars to include the extensive nebulosity. The first
image was merely exposed for 10 secs. at 1600 iso, whereas the
second needed 180 secs at 400 iso to bring out the surrounding
luminousity.
The Orion Nebula is the continuing birthplace of young stars. It
is about 1800 light years distance and some 30 light years
across.
Pleiades Cluster M45
In the constellation of Taurus, the 'Seven Sisters' cluster of
young stars can be seen with the naked eye. However, to see the
associated nebulosity requires a long exposure image to be
taken. This frame was exposed for 5 minutes at iso 400. It is
situated at a distance of 410 light years.
Andromeda Galaxy M31
This is the nearest galaxy to our own Milky Way at 2.2 million
light years distance. It is vast and consists of more than 300
billion stars and is 150,000 light years across. The image also
includes the smaller galaxies M32 and M110.
Great Hercules Cluster M13
This spectacular globular cluster is some 25,000 light years
distance and 100 light years across. It contains around 1
million stars. The image is made up of a stack of 60 sec.
exposures.
Black-eye Galaxy M64
The nickname comes from the partially obscuring cloud of dust.
This spiral galaxy is about 12 million light years distant. So
what we see here is the galaxy at a time when the great apes
were evolving towards our own Homo sapiens species appearing
only some 0.2 million years ago! See
Time-line graphic. This was the first galaxy I
ever saw. This image was produced from 10 x 45 sec. exposures at
1600 iso.
The Cigar Galaxy M82
About 12 million light years away in Ursa Major, this
descriptive image has been produced from an individual
frame exposured for 300 sec at 400 iso.
Spiral Galaxies in Leo M65 & M66
The view of these two distant galaxies at 30 million light years
away, means the light left around the time that cats began to
evolve, and millions of years in time before even a hint that
human beings would ever evolve in time to see this image! See
Time-line graphic. Currently,
this is the furthest object/s I have ever seen.
SUN
Our own star is 8 light minutes away. This 'white light' filter
image shows some of the major sunspot activity captured in late
October 2014. The area covered by the largest group would
swallow up the earth many fold!
MOON
Various images illustrating the phasing nature of our own
moon.
Globular Cluster M92
Another example of a globular cluster within the Summer
constellation of Hercules but about 25% further away than M13.
MARS
This image of the fourth planet from the Sun was taken with a
'web cam' attached to a x4 Barlow lens through the 8" Newtonian
telescope, as a video clip of 600 frames in a file of 0.6 GB
over 25 seconds. Selected frames were then 'stacked' to produce
this image. The rotation of Mars is very similar to that of
Earth, so the light /dark surface terrain only changes very
slowly on a daily basis. Note the ice cap.
COMET Lovejoy
This is the first comet imaged at the Ewelme Observatory. It was
discovered by Australian Terry Lovejoy in August 2014
using an 8" reflector telescope like the type we have here! It became closest to the Earth on 7th
January 2015 and will be closest to the Sun on 30th January.
It's travelling at 82,000 miles/hour and
is estimated that it will take another 8000 years to return! It
probably originated from the Oort Cloud, way beyond the bounds
of our Solar System. The
green glow is due to the fluorescence of diatomic C2
gas in sunlight. The hard to see tail in the first image is
because the exposure was only made for 60 seconds. With the
second image, light had to be exposed to the camera sensor for 5
minutes in order to see the four 'streamers' within the ion
tail. During this period of tracking the comet, it had moved
with respect to the background stars, hence the star elongation
effect.
On another infrequent clear night in January (16th), another attempt was made to enhance the ion tail. First, more room was made to extend whatever was to be seen of the streamers. Next, notwithstanding the extended star trails that would be present, the exposure time was doubled to 600 seconds (10 mins.). Finally, to attempt to improve comet image, a form of manual guiding was done by issuing a 'SLEW TO command every 30 secs,. using the comet ephemeris data within the Stellarium planetarium display. Three images are displayed to show the extent of travel of the comet compared against groups of stars in the background. Finally, the 'manual' guiding does seem to produce a slightly clearer image, but it can be seen that corrections in both RA and DEC were applied from the data provided. Click here to see a pseudo animation, which is attempting to show how fast the comet is moving across a 'static' star background during the couple of hours of observation.
However, it seems that the most successful way of taking an
image of a comet, is to stack many individual images, say 30 x
60 secs. If the proven procedures are followed, you should get a
nice focused comet with teased out tail. Unless removed, it will
overlay a neat, but promanent pattern of star trails. On 18th
January, attempts were made to gather many 'short' exposures,
but in the event only 9 x 60 secs frames were possible before
permanent cloud cover arrived. All that a standard DSS stack
produced was an egg shaped comet. By experiment, the image above
was produced, which although includes some 'false' colour,
showed that the camera had actually captured both the comet
nucleus itself but also recorded the whole tail within the 1.5
degree frame. The main 'unfalse' feature of this image, is that
there are no star trails, and for me, is
pleasant enough to look at, to be a contender for this year's
Christmas card!
Galaxy M96
Another spiral galaxy in Leo. On the current scale of images,
this is not very large or bright. However, this beats the record
for the most distant galaxy seen at 31 million light years. What
might have evolved on Earth during the space of time of 1
million years between receiving light from this one and
observing M65 and M66 above? The image consists of 12 stacked
frames with a total exposure time of 1 hour 12 minutes.
M101 Spiral Galaxy - The Pinwheel
I think my favourite to date, but is just a single 300 sec image with
no stacking as yet, I think this will be improved. Situated
within Ursa Major, this lies some 21 million light years
distant. See Time-line
graphic. It's diameter is about as large as our own Milky Way,
but is only about 8% of our mass.
M56 Globular Cluster in Lyra
Not an exotic image of one of Messier's catalogue objects, but
fascinating to notice how many stars are involved in this
picture within the same field of view as others above. This
particular image is an un-stacked (as yet) 2 minute
exposure at 800 iso.
M51 The Whirlpool Galaxy in Canes Venatici
This fascinating galaxy is really a large one
amalgamating with a smaller one due to gravitational
attraction. It is 23 million ight years distant from Earth. Perhaps it
is just a single object now, but thought can't travel faster
than the speed of light either? A 4 minute exposure at 800 iso.
Globular Cluster Collection - M10, M12 & M14
This group of star clusters are found in the same
region of sky around the constellation of Ophiuchus. It may seem
that these images, with similar fields of view of around 1
degree of arc and exposure times of 150 secs. at 800 iso,
is just an attempt to increase this observatory's album of 110
Messier catalogue objects. In many ways this is true, although
the 'M' cat does contain many of the worthwhile astronomical
wonders to both just observe and record. We are looking
back in time some 20,000 light years towards the centre of our
galaxy, at which time our ancestors were not themselves able to
write down that they were also able to see these faint fuzzies.
Double or Binary Stars
Not such glamorous images, but interesting all the same
in terms of the multiple faceted structure of the universe.
Double stars are those which are closely associated by gravity.
In other words they orbit each other. There are many well known
examples, and often the challenge is to be able to observe (or
resolve) both objects. Whether an observer can or cannot resolve
both can be a good indicator of the quality of the telescope
system. The first image is that of the Albireo double,
the main star of which represents the head of the summer
constellation Cygnus - The Swan. If you zoom in on the image,
you will better see the difference in colour between these two
stars indicating they are of different types and age. They are
430 light years from us and may take 100,000 years to orbit each
other!
The second image shows what is known as the double
double in Lyra. Although the two main stars can easily
be resolved in binoculars or small telescope, each of these two
stars is also a binary. However, my first effort has not yet
been able to resolve these into individual objects. Oh well,
something to strive for later!
M27 Dumbbell Nebula in Valpecula
This planetary nebula was first seen by human eyes by
Charles Messier in 1764. This light emitting object, mainly
caused by ionized oxygen, is the typical result of a
hydrogen fusion spent star, which collapses under its own
gravity and heats up to an extent that the outer shell is
expelled out from the central core. This nebula is about 2000
light years distant.
NGC 5907 Splinter Galaxy in Draco
This is an edge-on spiral galaxy, which one might imagine could
be the side view of the Pin Wheel Galaxy shown earlier. By
zooming in, one can see dust lanes partially obscuring one
narrow side of the galaxy. It is some 40 million light years
distant, or looking back to a time to when cats began to evolve.
M57 Ring Nebula in Lyra (with IC1296)
This nebula is also about 2000 light years distant as is the
Dumbbell Nebula, but is visually smaller on the same scale. It
was first seen by William Herschel, the discoverer of Uranus, 200
years ago. However, let me share my new world distance
record and include galaxy IC 1296,
enhanced and arrowed in the zoomed and brightened image adjacent.
The light from this dim and distant galaxy is seen and recorded
here in Ewelme as it was 200 million years ago,
at a time at the beginning of the Jurassic period when mammals
had just started to evolve, and 50 million years before even the
first birds flew on Earth!! See
Time-line graphic.
On the early morning of 28th September 2015, a session of 4 hours was spent in the 'control room' of Ewelme Observatory taking 100's of images of the complete cycle of the total eclipse of the Moon. The intention was/is to produce either a montage of images or an animation of the event. The problem with taking such images is that the difference between a fully light full moon, requiring an exposure time of 1/2000 sec, and a fully eclipsed one needing in the region of 20 secs. of open shutter, is to choose the best exposure times in between. So for a particular point during the eclipse, a selection of variable exposure times need to be taken in order to achieve reasonable contrast between light and dark. .An animation can be seen by clicking here, compiled from some of the images as an dynamic illustration of the various phases including totality . Margaret first saw this actual eclipse picture after switching on BBC Breakfast while I was still asleep in bed! You may like to compare this with the one I took in 2008, where the equipment consisted of an outside telescope and a compact camera, with heavy dew and cloud and only a few minutes of the Moon poking through. The next total lunar eclipse will be in the 2019, so watch this space!
M81 Bode's Galaxy
Some 12 million light years distant, this spiral galaxy can be seen in the same region of the sky as M82 - the Cigar galaxy (see above). The first picture, having been centred using 'plate solving', is the result of a single 5 minute noise reduced but unprocessed guided exposure downloaded from the camera sensor. Note that above the brightest star, a 'double star' has been resolved into two. This could be likened to what one might perhaps see directly through an eyepiece in terms of detail, although with a darker less noisy background. The second image is still a single exposure, but the range of light has been 'stretched' using Photoshop 'levels' to bring out the lighter wispy arms. Further guided images for stacking were also taken, and the result of stacking the best 9x5 = 45 minute exposures using Deep Sky Stacker, and then processing with Photoshop and Picture Manager, has yielded a final less noisy enhanced image of this galaxy for an evenings work. It would just be impossible to see such an image directly through a telescope eyepiece.
Comet Catalina 2013 US10
This is a 3.5 hour time lapse video of Comet Catalina 2013 US10 observed between 20:30 and 00:15 on the 19th January 2016, showing how surprisingly fast a comet can move within our Solar System over a short period of time. This one is travelling at approximately 35 Km/s, and during this record has travelled between the constellations of Draco (left) and Ursa Major (right) some 460,000 Kms while rising in altitude about 20 degrees. A.YouTube entry can also be seen at https://youtu.be/0K9gqUi88XU