Space does not look like that

J. Karl Miller wrote: please note,

Our son Derek K. Miller, along with a degree in marine biology, a diploma in non-fiction writing, had an eclectic mind, and interests in many things ranging from writing for several magazines, the Vancouver Sun, and other publications, and editing books. He also had extensive knowledge of and involvement with science, music, photography, computer technology, web page programming and administration, astronomy, and several other fields. He was among the first to make use of on-line communications, well before the internet existed in its current form.

This post is a copy of what Derek wrote in his blog about two and a half months before he died of metastatic colorectal cancer at age 41.

By Derek on February 17, 2011 6:40 PM 

Remember the end of The Empire Strikes Back, where Leia and Luke, convalescing from surgery to replace his severed hand, gaze out of the window of a Rebel spaceship at the departing Millennium Falcon, with the Galaxy (the far, far away one) spinning slowly in the background? It looked something like this:

Hubble image

That's a real galaxy, though, called NGC 2841, about 45 million light years away from our own. And neither it nor its Star Wars companion would look anything like that if we were seeing them with our own eyes.

First of all, forget the spinning: it takes our solar system about 225 million years to make one rotation around the core of the Milky Way, so even if you were able to see the whole disk, it would take many human lifetimes to perceive any motion at all. Put another way, the last time we were at this spot in our rotation, Earth was in the middle of the Triassic period, the time of the earliest dinosaurs.

Maybe more importantly, I don't think we could see a galaxy in all its beauty that way at all, because it would probably be too dim for our eyes. Consider that all photos of other galaxies require pretty long exposures, even for sensitive equipment. The Andromeda Galaxy, which you can see in a dark sky with your naked eye as a faint smudge, doesn't show its full shape in a telescope until you collect light for at least a few minutes.

Consider the fact that we're right inside a galaxy, and for most of us living in cities, the Milky Way, which is the view through the thickness of our closest spiral arm, is entirely washed out by light pollution. I don't think my daughters have ever seen it, in fact. You need a pretty dark sky, preferably on a moonless night, to see it properly.

If you were far enough away from a galaxy to see the whole thing, it would be even dimmer, so no matter how dark the sky, to your naked eye it would be much more a large, galaxy-shaped smudge of light (an impressive smudge indeed, but still smudgy) than the crisp, defined, and detailed colourful disks we see in photos. You might be able to determine its shape, and see the core, but it wouldn't be what Luke, Leia, R2-D2, and C-3PO were gazing at.

People are sometimes disappointed when they look through a telescope at celestial objects. Jupiter, Saturn, the Moon, and the Sun are certainly impressive, but nebulae lack the fantastic colours and flaming tendrils we've come to expect after decades of Hubble Space Telescope images. But those pictures are long exposures, often with artificial colours displaying wavelengths humans can't even see.

While those images are real, they're not what our eyes see when we look at the light directly.

Still, think about how amazing it is to do anyway: away from city lights, on a dark clear night, preferably at high altitude, you can peer up near the constellations Pegasus and Cassiopeia to find the Andromeda Galaxy, no binoculars or telescope necessary (though they'll make it yet a better experience). When you see it, you know that the light hitting your eyes started its journey two million years ago, before modern humans evolved. 

Getting to know the sky

At our public star parties a number of people have never seen the impressive objects we usually show through a telescope ask about how, and at what cost they could acquire a telescope to look at the stars, planets, the Moon, and other objects in the sky.

My long-time come-back to this question for people who are new to looking at the sky through one of our members' or SFU's Trottier observatory's telescopes are questions of my own. I ask whether they own a pair of binoculars. If the answer is yes, then the my next question is: have you ever looked at stars through them? Many people have never even thought of doing this. To those people who have done it, I put this question: would you know where to look for the Andromeda galaxy (or some other object in the sky)? The answer many times is "no".

With the apps available on computers, tablets, smartphones, etc., many people compare the sky portrayed on these devices with the sky visible at the time. That's a legitimate approach, but, in my opinion, if one comes to rely on these devices, one usually does not "learn" the sky.

I grew up at a time when these devices were "science fiction". Having had an interest in astronomy since I was eight years old, knowing the sky is an "innate" feeling for me, at least as far as the northern hemisphere is concerned. I've not much time closer to the equator, therefore I don't have the same familiarity with the southern sky.

In my younger years I did some serious astronomy, for instance submitting observations to the AAVSO (American Association of Variable Star Observers) regarding variable stars, Zürich sunspot numbers, occultation timing, and other things. These activities, and many others are now done by both amateur and professional astronomers (the two categories really overlap nowadays, since the technologies available are now highly sophisticated and not very expensive), and generate very precise and detailed results.

At this time in my life, my greatest enjoyment comes from our public star parties. I get a kick out of comments like "wow", "cool", "amazing" when people are looking through one of my telescopes at the sky. In particular, I feel very happy when a young person comes up with these comments.

Adults who are "newly exposed" are equally amazed. The objects which usually are the source of this are the "jewels" of the sky: Venus and its phases, Jupiter and its moons, Saturn's rings, our Moon's craters, open and globular star clusters, etc.

Here are the recommendations I usually make:

(1) When outdoors, preferably under a dark sky, use only your eyes to get to know the sky and constellations using one of the star finders we hand out freely on various occasions, or find a printed or on-line star atlas. Familiarize yourself with the constellations and their annual positions at various times of the year. Dig deeper, and become knowledgeable about the Earth's orbit and how that relates to these times of visibility. Try to find objects which our unaided eyes can readily perceive (Pleiades, Hyades, Milky Way, compact constellations, etc.). If you feel that you'd like to see these targets in more detail, then

(2) use your binoculars to find these objects. If you are a young person, 7x50 binoculars are ideal. Your age and personal preferences have an effect on what may be your perfect binoculars. Almost all binoculars will show far more detail in the night sky than the "naked" human eye. Using binoculars will "train" you to find sky objects. At first you may spend some time to succeed, but you quite quickly become better at it.

Many very descriptive dissertations have been written about the use of binoculars in astronomy. Even advanced astronomers, at least those who are involved in the visual observing, have their favorite binoculars on hand when observing. Personally, when I'm setting up one of my telescopes, I always have binoculars with me. They are very helpful in locating objects for which I want to use the telescope. Once you have become familiar with their use and characteristics, and if you are looking for even more detail, a telescope may be your next "step up".

(3) Before you buy a telescope, understand the basic requirements. Beside the size of your contemplated purchase, understand differences between the various types. This is a much-discussed and written-about subject. The best way to find out is to attend star parties, such as the ones run by the RASC, or SFU's Trottier Observatory, because you will usually meet people who are using different types of telescopes. You will also become aware of the fact that purchasing a telescope entails having to buy a sturdy, and accurately manufactured telescope mount. The best telescope is next to useless unless it can be held steady, and does not shake with every little breeze. The matching of telescope to its support is another important topic.

Computerized telescopes are a helpful addition to the range of telescopes available. Again, unless you have learned how to find objects in the sky as described in (1), (2), and (3), you likely won't get to know the sky in the detail necessary. Getting to know the sky "in depth" is best done by learning to point a telescope "manually".

If you become a member of the RASC, you'll have access to many benefits. As a member, you can borrow one of the RASC's library books, and/or a loaner telescope for a limited time. You also receive several publications, chief of which is the RASC's annually published Observers' Handbook. It contains a wealth of data, among which you'll find detailed information about binoculars, telescopes, human eyes, and upcoming monthly events (eclipses, occultations, planetary positions - a plethora of facts and discoveries). The Handbook is used by professional and amateur astronomers world-wide. The RASC also owns the magazine "Skynews", and publishes the RASC Bulletin and local RASC centre newsletters. All these are included in the membership.

Try it - I think you'll like it.

Deja vu (Perseids wiped out again)

As is a tradition by now, our local centre of the Royal Astronomical Society of Canada helps out at
Aldergrove Lake Park for viewing the Perseids every year. It is a big event for the Parks Board and the public, and matches the Royal Astronomical Society of Canada's mandate to promote an interest in astronomy and associated sciences to the public.

I wrote this last year in my post about viewing the Perseid meteor shower (August 13, 2017, in italics):

Aldergrove Park near Abbotsford is used for public viewing when the Perseid meteor shower peaks annually on August 12. The park administration sets up a tent for us (the RASC), and reserves some space nearby to set up telescopes. Some of our members, and sometimes invited speakers, give several talks regarding astronomical events (past, present, and future). It's a rain-or-shine occasion. If it rains, telescopes are not set up outside, but may serve as exhibits inside the tent.

The Aldergrove Park administration promotes this event. This is the only time in the year at which overnight camping is allowed in the park. Many people usually attend.

This year, an unfortunate fire on a barge carrying old, recycled cars, docked in the Fraser river on the day before this event created a lot of smoke. This affected much of the Lower Mainland, both on the day before, when we were involved with the "Starry Night" event at Simon Fraser University's Trottier Observatory, and at Aldergrove Park. "Perseid" day itself was cloudy, with local rain showers. Toward evening, the smoke had cleared, and some large, blue stretches appeared in the southwestern sky and drifted east to where Jupiter, Saturn, and Mars would be located at dusk. I made my way to Aldergrove Park, found our assigned area (same as last year), decided that chances were reasonable for viewing, and set up my telescope.

Our RASC Vancouver centre librarian William happened to spot Venus with his binoculars well before sunset, so he and I trained our telescopes on that brightest of our planetary siblings. I got a couple of minutes view of it, a couple of members and the public had a chance to view it as well, and then a cloud covered Venus. That was the last view I had of it for the evening.

Well, as the weather gods would have it, it turned more cloudy just as the evening approached and eventually some rain began to fall. I packed up my telescope. There was another break in the clouds about 45 minutes later and a number of people had a chance to see both Jupiter and Saturn through a couple of our other members' telescopes. Clouds then turned really heavy, and it started raining seriously towards 11pm.

After the a number of days of wildfire smoke, which covered our area during all the preceding, sunny days, and which was finally cleared out by wind from the south-west, this was a disappointment.  We are told by the park administration that fewer people than last year showed up. During the short periods when the view was worthwhile, several dozen of them came to visit our telescopes. Attendance at the talks in the tent was fortunately much higher.

Our activities ended just before midnight; had it been clear, we would have stayed all night for the public to have a look at interesting astronomical objects - the Perseid meteors especially, of course. Well, we hope that next year's Perseid meteor date will have a clear night sky. This is the same sentiment I expressed last year.

As I write this, the smoky sky has returned. The cause appears to be some fairly large forest fires on Vancouver Island. So the night from August 12 to 13 (which was when the actual maximum of Perseids was expected) turned out to be a bummer, too.

Maybe "deja vu" of smoky skies is turning out to be the new normal.

Smartphone Moon

On July 21, I set up my trusty 3" refractor (f16), which I bought 54 years ago, and used a Meade 20mm eyepiece (which I've had for close to 40 years) to look at the Moon, Jupiter, etc. I invited my neighbour, Trevor, to have a look. It seems that he had never seen the Moon close up. He was very impressed and wondered if a smartphone could be used to take a picture.

I told him that it would be possible, but challenging to manually align the smartphone camera lens with the eyepiece.  Well, he tried anyway, I helped him to line up the lens. During the short moments that a good image appeared on the smartphone screen, a couple of pictures were taken. Here's an image of "Trevor's Moon", taken with his Samsung smartphone. Quite acceptable, although the dynamic range seems a bit narrow. I have added "enhanced" pictures (modified from the original) to show more cratered area detail. The highly overexposed bright areas did not contain enough detail to recover.

"Trevor's Moon" (original image, downloaded from his smartphone)

Cropped from the original image.

Image enhanced to show more details in cratered area.

Southern, cratered section of the Moon enlarged.

Enhanced to show more detail.

The prominent craters Tycho and Clavius show up well, including the craters inside Clavius. I was surprised that this makeshift arrangement had such a good result. Amazing what one can do with today's smartphones and graphics programs.

I'm thinking of buying one of the available smartphone camera attachments (I have an iPhone 6s) and, on our public nights, have people activate the camera button. That way, they could  photograph the craters of the Moon themselves (I'd email the image to them). It might be popular for SFU's Starry Nights, and our "side walk" RASC events.

The Moon and Venus and other goodies

Friday, July 20, 2018

It's a feeling I get many times when, at times when some of the major planets in our solar system are visible at a given time, I appreciate the enormous distances of the planets from Earth. In the two images below, the Moon and Venus show the two "in conjunction (July 15, 2018)". This is purely a local, and temporary perspective. The two pictures were taken well over an hour apart. You can clearly see the Moon's motion in its orbit - it moves about a half a degree per hour (0.55 degree).  From Earth, the Moon is about 1/2 (0.5) degree in apparent diameter, so it moves it's own diameter in an hour. Since the Moon has an actual diameter of very close to 3,500 kilometers, it travels at 3500 km/hour.

Moon and Venus

Moon and Venus after well over an hour later

Venus (almost Earth-sized) was about 370 times farther away than the Moon at the time. It took Venus's light about eight minutes to reach Earth, from the Moon 1.3 seconds. 

Right now, late middle of July, in addition to the Moon and Venus, there are a few showpieces in the evening sky: Jupiter, Saturn, and Mars. While Jupiter and Saturn are always of interest to the general public, Mars is usually quite small, and few details are seen on its surface. At this particular time, though, Mars is approaching a close position to Earth, and more details would normally be visible. As fate would have it, a planet-wide dust storm is raging on that planet, which is obscuring much of its surface. That storm is bad enough to affect the still working rover vehicles (Curiosity and Odyssey) which have been put on its surface. anything that uses solar power has been put into "low-power" mode and is not sending back any data. The concern is that those with back-up batteries will run out of electrical power if the storm lasts much longer. Here's an image from the Jet Propulsion Laboratory in Pasadena:

On the left, is Mars as it normally appears in a large telescope, on the right is the storm-obscured equivalent. Let's hope that it clears up soon.

Hoo, hoo, hoo...

The Owl Nebula (M97) - unprocessed original image

(remotely photographed through a Slooh.com telescope)

The Owl Nebula (M97) in Ursa Major

cropped from original and processed with Apple Preview

I've been away for the better part of the last two months, and, being back home, decided to pursue my astronomical activities by using one of Slooh.com's remotely-controlled telescopes.

About 2030 light years distant, in the constellation Ursa Major, you can find the Owl Nebula (M97). In 1781, the French astronomer Pierre Méchain discovered this planetary nebula. At a time when there no photographic technology, some observers drew the nebula image resembling an owl's head. That appears to be the source of the name. Here is a description found in Wikipedia:

The nebula is approximately 8,000 years old. It is approximately circular in cross-section with a little visible internal structure. It was formed from the outflow of material from the stellar wind of the central star as it evolved along the asymptotic giant branch. The nebula is arranged in three concentric shells, with the outermost shell being about 20–30% larger than the inner shell. The owl-like appearance of the nebula is the result of an inner shell that is not circularly symmetric, but instead forms a barrel-like structure aligned at an angle of 45° to the line of sight.

The nebula holds about 0.13 solar masses of matter, including hydrogen, helium, nitrogen, oxygen, and sulfur; all with a density of less than 100 particles per cubic centimeter. Its outer radius is around 0.91 ly (0.28 pc) and it is expanding with velocities in the range of 27–39 km/s into the surrounding interstellar medium.

The 14th magnitude central star has since reached the turning point of its evolution where it condenses to form a white dwarf. It has 55–60% of the Sun's mass, 41–148 times the brightness of the Sun, and an effective temperature of 123,000 K. The star has been successfully resolved by the Spitzer Space Telescope as a point source that does not show the infrared excess characteristic of a circumstellar disk.

In terms of the age of the universe, this nebula is like a newborn owl. 

hoo, hoo, hoo...

Southern Belle

 Rain, rain, rain... my astronomical activities are certainly taking a bath right now. Fortunately, in this age of the internet, I can hook up with some remote-control telescopes, located in areas which are much more likely to have clear skies. One such telescope is located in Chile and is made available to members of Slooh.com, an organization oriented to the world-wide astronomical community.

Some of the most impressive astronomical objects are located in the southern sky, visible at night only from areas close to, and south of the Earth's equator. One of those objects is Eta Carina.

Here is a quote from Wikipedia, the free encyclopedia:

The Carina Nebula (catalogued as NGC 3372; also known as the Grand Nebula, Great Nebula in Carina, or Eta Carinae Nebula) is a large, complex area of bright and dark nebulosity in the constellation Carina, and is located in the Carina–Sagittarius Arm of our galaxy (Milky Way). It has an estimated distance between 6,500 and 10,000 light-years (2,000 and 3,100 parsec) from Earth.

The nebula is contains many other objects, from the intrinsically brightest star in our galaxy to several star clusters, gaseous star-forming regions, and other interesting sights.  It is one of the largest diffuse nebulae in our skies. Although it is some four times as large and even brighter than the famous Orion Nebula, the Carina Nebula is much less well known due to its location in the southern sky. It was discovered by Nicolas-Louis de Lacaille in 1752 from the Cape of Good Hope.

a wide-field view of (η) Eta Carina

Here's a larger image of Eta Carina Nebula's core.

At this time, we have no plans to travel south; from a narrow point of view, to take a photo of this nebula/star assembly remotely saves the money. None-the-less, it would be nice to see this southern belle directly, it is a beauty even in binoculars, though you won't see the colours seen in the two images.

Astronomical gems

Something which is unfortunately not seen from our latitude is one of the oldest and likely the largest concentrated accumulation of stars in our galaxy. It is a globular cluster, of which there are about 200 or so associated with "us". These clusters are very old, they have been around for about 10 to 12 billion years. Our own universe is calculated to be about 13.7 billion years old, so they have existed for most of that time.

This particular one is best seen from the night sky close to, and at latitudes below Earth's equator. It can be seen by the naked eye as a fuzzy star in the constellation Centaurus, and is accordingly named like a star: "Omega Centauri" (a mix of a Greek letter and Latin constellation name). It turns into an amazing view when seen through a pair of reasonably large binoculars or wide-field telescopes. As a photographic object, it truly "shines", much like a box of diamonds.

Since it is unobservable from our area, and since the current weather prevents any outdoor observing of the sky, I decided to resort to "old trusty", and acquired an image of Omega Centauri via a remote-controlled Slooh.com telescope, located in Chile. This is a favorite object for many astrophotographers and has been recorded thousands of times. Robert Conrad, the Observing Director in our Vancouver centre of the RASC posted his excellent photo in NOVA (March/April edition), our bimonthly news letter.

Here is my wide-field image of Omega, cropped to centre it in the frame:

Omega Centauri

This globular cluster contains about four million stars. That is about 10 times the number contained in M13, the most impressive globular in our sky (but not visible with my unaided eye, at least). Some estimates say that the average distance between the stars in Omega Centauri is less than one light year. Can you image the blazing night sky you would see on a planet that orbits one of those stars?

The orbits of planets around any of these stars would likely be perturbed by the other close near-by stars to make them unstable, with local climate subject to large swings from hot to cold. That would make an evolution of life as we know it unlikely. Well, it's nice to speculate.

Something "new"

 Nova

N CMa 2018

At left of the two pictures below is the pertinent cropped section of the nova image I obtained using a remote-controlled Slooh.com telescope. For reference, I reproduced a section of the map produced by Robert Conrad, using the American Association of Variable Star Observers AAVSO Variable Star Plotter regarding the AAVSO Alert Notice 627 in relation to the discovery of the nova. The nova was discovered in Japan on March 24 by Yuji Nakamura in Japan using a 4" photographic reflector telescope (called an astrograph). Robert Conrad, who is our Director of Observing at our Vancouver RASC centre, and who diligently digs out and observes new events in the sky, notified our observers about this. Spectroscopic observations, using larger, professional telescopes, classified this nova as the classical type.

P

 Left: Image of Nova      Right: A section of AAVSO map of Nova location.

Here is an excerpt from Wikipedia:

Classical nova eruptions are the most common type of nova. They are likely created in a close binary star system consisting of a white dwarf and either a main sequence, sub-giant, or red giant star. When the orbital period falls in the range of several days to one day, the white dwarf is close enough to its companion star to start drawing accreted matter onto the surface of the white dwarf, which creates a dense but shallow atmosphere. This atmosphere is mostly hydrogen and is thermally heated by the hot white dwarf, which eventually reaches a critical temperature causing rapid runaway ignition by fusion. From the dramatic and sudden energies created, the now hydrogen-burnt atmosphere is then dramatically expelled into interstellar space, and its brightened envelope is seen as the visible light created from the nova event, and previously was mistaken as a "new" star. A few novae produce short-lived nova remnants,^[1] lasting for perhaps several centuries. Recurrent nova processes are the same as the classical nova, except that the fusion ignition may be repetitive because the companion star can again feed the dense atmosphere of the white dwarf.

Novae most often occur in the sky along the path of the Milky Way, especially near the observed galactic centre in Sagittarius; however, they can appear anywhere in the sky. They occur far more frequently than galactic supernovae, averaging about ten per year. Most are found telescopically, perhaps only one every year to eighteen months reaching naked-eye visibility. Novae reaching first or second magnitude occur only several times per century.

More details can be obtained by linking to https://en.wikipedia.org/wiki/Nova .

You can't be bored if you are interested in astronomy. There is always something new in the sky.

Serendipity

On March 11, at late dusk, I happened to walk out onto our back porch, and, as is usual for anyone into astronomy, I looked up at the sky. In a gap between a neighbour's house and a bush across the laneway separating us, I spotted a fairly bright object. It was not so bright as Venus would be, but about the brightness of Jupiter. Waiting for a minute or so to make sure it wasn't some distant airplane approaching our international airport, I decided that this object was likely the planet Mercury. Knowing that Mercury was near the most favourable (for our latitude) elevation this year, I quickly checked the position using one of my computer programs and grabbed my 60Da camera, went back outside, aimed, and took a picture. The camera was set on manual, unchanged since I last used it for the lunar eclipse described in my January 31 post. 

The screen showed only Mercury and a trace of street light reflection on the gutter of the above-mentioned house, otherwise, things were completely black. In other words, the image was severely underexposed. So I attempted another shot with a more appropriate setting, but nothing happened. Another one, again nothing. I finally realized that the the battery indicator showed a completely discharged battery. I went inside to swap in my spare, and making sure the camera was operating normally again, then went back outside, only to find the Mercury had sunk out of sight. So the underexposed image was the only one available. 

With the help of the Preview program in my laptop, which has some elementary processing features, and Photoshop, I began trying to squeeze as much as I could out of that image. The final result was of poor quality, but none-the-less, it showed sufficient detail to display what the view was like. It's amazing what one can do with today's graphics programs. In the days of using and developing colour films, and printing colour prints in my own (chemical) darkroom, this feat would have been impossible.

Here is the processed picture:

The original image:

Mercury is the planet closest to the Sun. As a result, it is usually hard to see it because appears only close to the Sun most of the time, and is swamped by a bright sky. Many people have probably not seen the planet Mercury "live" before, even many professional astronomers in the past, and perhaps even now.

The second of Mercury's greatest "Sun separations" (the proper name is elongations) this year, from the Earth's point of view, occurs on March 15, it will be somewhat higher in the sky than shown in the picture above. The weather since the 12th has been cloudy and rainy, so I haven't been able to see Mercury since. This planet's elongations occur several times a year, this year there are seven, three in the evening, and four in the morning. The current evening one leaves it high enough in our local sky to make it the best of this year for us. 

Since I saw Mercury this time only by coincidence, I'd say this was a serendipitous occasion.

A follow-up:

On March 15, when Mercury was at its greatest elongation, as mentioned above, the sky was clear, and I set out to photograph both Mercury and Venus at dusk.

Here's the picture (processed to enhance contrast). It is a hand-held Canon 60Da photo through a Sigma 18 - 200mm telephoto lens, set at 100mm, f8, 1/20sec, ISO 800, slightly cropped:

Bubble Nebula and M52

Lately, I've had the bad luck to try for some images on the Slooh.com telescopes on the Canary Islands. These remote-controlled telescopes have been inactive for the last few times I've tried to capture images, due to unsuitable weather. A couple of months ago, I used one of the remote-controlled telescopes on December 20, 2017 to get an image of both M52 and the Bubble Nebula (both located in the Cassiopeia constellation). Here is a picture:

Star cluster M52 at upper left,  Bubble Nebula at lower right.

Classified as an open star cluster, Messier 52 (NGC 7654) is located in the Cassiopeia constellation. It was discovered by  Charles Messier in 1774. M52 can be seen with binoculars. Distance estimates range between 3,000 and 7,000 light years. This uncertainty is caused by interstellar absorption of light. There are an estimated 190 stars in the cluster. The poorly known distance, and the numerous foreground stars make a determination of a more accurate number of cluster members difficult to determine.


The Bubble Nebula (NGC 6735), is a Hydrogen emission nebula also located in the constellation Cassiopeia (you'll need a minimum 10" telescope and a dark sky to see it faintly). The stellar wind from a massive hot, young central star is the cause of the "bubble”. The nebulous cloud itself is illuminated by the hot central star whose high-energy light is causes the cloud to glow. William Herschel discovered the cloud in 1787. Its distance is also uncertain, interstellar light absorption affects estimated distance, which is listed as 7,100 - 11,000 light years. The star causing the bubble is thought to have a mass of about 44 times the mass of our Sun.

Blue, blood, and "Supermoon" eclipse

On January 31, 2017 morning, I got up to have a look at, and take some pictures of the total lunar eclipse which has been hyped as the "blue, blood, eclipsed Super Moon". As the weather gods would have it, there were variably transparent clouds everywhere. I took a total of 356 pictures, many of which were of poor quality because of this. To control the camera, which was attached to a tracking mount, I used my 27" iMac, loaded the Canon EOS control program, and connected the camera to one of the computers USB ports. The program allows remote control of various camera functions, including exposure and ISO ratings.

I set up the Canon 60Da camera at the window inside my office. This window is on the west side of our house and fortuitously looks out on that part of the sky in which the eclipse took place. An old Pentax 200mm and a 2x Barlow lens (both Pentax threads) resulted in an effective 400mm telephoto lens; this combination was attached to the 60Da by means of Pentax-thread-to-Canon adapter. In order to get reasonable quality images, I opened the office window, and took out the mosquito screen. That meant that the office got really cold; when daylight arrived there was frost on the roof of houses and frosty cars. To make this 5-hour photo session more comfortable, I set up my MacBook Pro laptop, using VNC, to communicate with the iMac in the office over my internal computer network. VNC was set to show and control the iMac screen in the office. I set up the MacBook in the kitchen to keep warm and kept the office door closed.

Here is a picture taken near the beginning of the eclipse:

The Moon at the beginning of the eclipse (with clouds - image cropped from a wider original)

The cloud situation was variable throughout the whole eclipse. This meant that I had to experiment continuously with exposure times and ISO settings (the reason why I took so many images). But whenever I hit the correct exposure, I could suppress the clouds and bring out the actual image of the eclipsed moon. This image was taken under those conditions:

The partial phase - the bright part is highly overexposed in order to bring out the colour inside the Earth's shadow. This colour of the shaded part is caused by the Earth's atmosphere refracting the Sun's light into the shaded part. If you were on that (shaded) part of the Moon, the Sun would be covered by the Earth, but Earth would be surrounded by a red "sunset" ring.

This is an image of the Moon at mid-eclipse through a fortuitous, short "clear" hole in the clouds:
 

The Moon at maximum eclipse.  It is illuminated by the Earth's atmosphere's refracted sunlight light only.

The cloud situation got worse after the eclipse total phase was finished. The Moon was also much lower in the west. Here's another through a "cloudhole" shot. It was the last clear one:

Partial phase past totality.

The final image below. A thick bank of clouds rolled in and covered the Moon completely. The variable clouds earlier fortunately occurred in the right time frame to see most of the eclipse.

"Good bye". The thick black cloud bank spelled eclipse end for me.