Thursday, September 21, 2017

End of (star) life

 When old giant stars come to the end of their life, they often expel copious amounts of their atmosphere into the surrounding space. What remains behind is their extremely hot central cores, which emit a lot of their light in the ultraviolet range of their spectra. This high-energy light makes the ejected atmospheric gases fluoresce in a variety of colours and gives a hint of what elements they contain. That helps determine the chemistry of the star of which these gases were originally a part.
These fluorescent gases are called a "planetary nebula". This is a misnomer, they are nothing like the planets in our solar system.

 Here is a picture of the first planetary nebula discovered - the "Dumbbell Nebula", which I obtained via a remotely controlled telescope (located on the Canary Islands):

A concise explanation for the theories regarding the cause and reasons why planetary nebulae exist can be found here:

Not all stars end their life being surrounded by a planetary nebula. It appears that the mass of a star plays an important role in their generation. The sun is likely too small for this to happen.

A colorful way to go...

Tuesday, September 19, 2017

A Very Long Way Out

One of my astronomical activities I personally much enjoy are the public daytime and nighttime astronomy events. Among the objects we observe are the Sun, the Moon, our planetary system, and "deep sky" objects, such as star clusters, gas nebulae, and our own galaxy, as well as far away galaxies. I'm particularly happy when people exclaim a "wow" about what they are seeing (nowadays the word is probably "cool"). Among those objects is the planet Saturn with its rings and moons, Jupiter and its moons, the planet Mars (when it is close to Earth), our Moon with its craters, the planets Venus with its phases and Mercury - difficult to see because it is so close to the Sun. Usually, we can see some of these "spectacular" objects in the sky at the same time.

This brings me to the subject of distances in our own solar system. By definition, the average distance from the Sun to the Earth (150 million kilometers) is called an "Astronomical Unit", AU for short. It takes light more than eight minutes to travel that distance. So we see the Sun as it was over eight minutes ago. Light travels 300,000km in a second - it could travel around the Earth (circumference 40,000km) more than 7 times a second. The average distances from the Sun to Mercury is about 1/3 of an AU, to Venus 2/3AU, Earth 1AU, Mars 1.5AU, Jupiter 5.2AU, Saturn a little less than 10AU, Uranus 19.2AU, Neptune 30AU,  Pluto varies from about 40 to less than 30 AU, it was recently closer than Neptune. We can see all the planets only because they are illuminated by the Sun; we see them in"reflected" sunlight.

The distance light passes in each minute can be called a light minute, so the Sun is over eight "light minutes" away. Similarly, the distance traveled by light in an hour can be called a "light hour", distance traveled by light in a year is a "light year" - the standard unit for expressing the distance to stars, Nebulae, other galaxies and anywhere else in the universe outside the solar system.

The planets beyond Saturn look less spectacular in a telescope; they get as less attention on our public nights. It is possible to gain a better "look" by taking pictures through telescopes. Here is an example of the planet Uranus, I took through a remote control telescope, located on the Canary Islands.

The three faint "stars" you see next to Uranus are some of its moons. They are fairly difficult to see, because the brightness of Uranus. I processed the image in Photoshop to make them more easily visible.

As mentioned above, Uranus is a little less than 20 AU from the Sun. That means that it takes sunlight more than two-and-a-half HOURS to reach Uranus, and another two-and-a-half hours for that reflected sunlight to get back to Earth. Nothing can travel faster than the speed of light - our fastest spacecraft can travel at most about 50,000km per HOUR at present. That's equal to 13.9 km per second, which makes it about 21600 times slower than the speed of light, i.e at a speed of 50,000 km/h it takes 26,100 times 2.5 hours (6.1 years) to reach Uranus, travelling in a straight line. However, all orbits around the sun and the travel paths of space probes are curved, so the time that trip takes is even longer. No wonder that it takes many months or years to get to any of the other planets at speeds we can achieve with present rocket technology.

Now, if you want, consider how long it would take for us to reach even the nearest star, which is over 4 light years away, with our currently fastest spacecraft.

The universe is huge, and things are A Long Way Out.

Monday, August 21, 2017


To show today's partial solar eclipse (it was not total here) to the public, several of us - members of the Vancouver Centre of the Royal Astronomical Society of Canada (RASC) - set up solar and "white light" filtered telescopes at Telus Science World here in Vancouver. We also gave out hand-held eclipse viewers - we had a limited number, and have none left now.

The eclipse had been advertised extensively world-wide. Telus Science World (and we) anticipated a large crowd, and that certainly was the case. People queued up more than hour before the beginning of the eclipse. The line-up at each of our telescopes was in the hundreds all through the eclipse; someone mentioned that a total of about ten thousand people were in attendance inside Science World and at our telescopes. It was a grand occasion. We have had similar reactions at other events (though not the huge crowds of today). I think it shows that, when it comes to finding things out about what goes on in space, people have an innate interest.

At the time near maximum of the partial eclipse, when the sun was only a crescent reminscent of a young or old Moon, the sunlight turned into an unusual bluish/gray colour and was noticeably fainter. A drop in temperature was also felt by most people. It is odd to see faint sunlight under an absolutely clear sky. It was not like sunset or sunrise - those are commonly red.

This was a very successful event; perhaps we have steered a few young people in the crowds to study and get involved with working in astronomy, and/or related sciences. There is really no boundary between any of the sciences; STEM technologies underly most of them, particularly astronomy and space travel.

Why don't we order up another eclipse soon, we all had a great and fun time.

Sunday, August 13, 2017

The missed Perseids.

As is a tradition by now, our local centre of the Royal Astronomical Society of Canada helps out at Aldergrove Park near Abbotsford when the Perseid meteor shower peaks annually on August 12. The park administration sets up a tent for us, and reserves some space nearby for us 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. Over a thousand people usually attend.

Well, as the weather gods would have it, it turned cloudy just as the evening approached, and started raining towards 11pm. After the eleven 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. None-the-less, we are told by the park administration that about 1500 people showed up. During the evening, several hundred of them came to visit our telescopes and tent.

Since we had hoped for some break in the clouds, we set up about half a dozen telescopes early in the evening. Well, there were no breaks, so we ended up looking at the details of distant trees, and also explained to a number of curious campers how different types of telescopes work, and why they are a primary tool for the exploration of the universe. We packed up our telescopes just before the rain started; the talks in the tent continued. 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.

After the lengthy period of enforced astronomical inactivity, due to the smoke, to satisfy my wanting to do something about it, and before the event at Aldergrove Park started, I had set up a session to automatically take a picture of Fireworks Galaxy, in which a new supernova recently appeared. This galaxy is the home of ten recent supernovae in the last century; there may have been others of which we are unaware before then. This is an unusual frequency of such events in any given galaxy.

The remotely controlled telescope on which I reserved time to take the image is one of several located on the Canary Islands. These telescopes are dedicated to the use of the astronomy community world-wide. Here is a description in Wikipedia:

I retrieved the Fireworks Galaxy image from this morning and did a bit of processing on it with Photoshop and Pixelmator. Here is the original:

The original image shows almost no trace of the Fireworks Galaxy
(compare to the processed image below)

Processed with Photoshop and Pixelmator

 Cropped, and enlarged.

As usual, click on each image to see a magnified version.

Patrick Wiggins, in Utah, discovered this supernova on May 14, 2017. Some type of stars go "supernova" at the end of their lives, when they have used up most of their internal "fuel". A good description of supernovae is found here:

Even though we did not see the Perseids,  I at least got something astronomical out of yesterday.

Tuesday, July 25, 2017

Again Astronomy

The nice, warm weather we're having at this time inspired me to take another picture from my very limited view of the sky here at our house. We're located close to Metrotown (lots of light pollution) and our horizon is blocked by high-rise buildings and close-by trees.

The original image of M13 - the fuzzy "star" at the middle right.

The cropped and enhanced image of M13

The original fainter image at the top, showing a little fuzzy patch, is a picture of the globular cluster M 13 in the constellation of Hercules. Exposure was 30 seconds, ASA 800. This "source image" was taken with a 200 mm lens coupled to a 2x Barlow lens, making the combination equal to a 400 mm lens. The effective f-ratio was f 8.

The close-up is an enhanced image of M 13. You can see that the source image contains a lot of hidden detail. The camera used is a Canon 60Da, the source image is in "Raw" format, which preserves much of the detail captured in the image. The detail can be extracted with appropriate graphics software (I used Pixelmator and Preview for this purpose). 

Click on the images for a larger view.

We call our galaxy the "Milky Way" because we're inside it and it appears to us as a "stripe" of stars in the sky so numerous and faint that they melt together to look like "spilled milk". The globular clusters surround our otherwise "pancake-shaped" galaxy in a kind of sphere centered on the core of our galaxy. Other galaxies also have globular clusters. Globular clusters are considered to contain some of the oldest stars in our galaxy. There are estimated to be somewhere between hundred thousand and a million or so stars in each globular cluster. You can see a detailed picture in my previous post regarding M53, another "local" globular cluster (

Wikipedia describes them like this: A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. Most globular clusters in our galaxy show a lack of O and B type stars, an indication of their great age. The globular clusters in the Milky Way are all estimated to be at least 10 billion years old and therefore contain some of the oldest stars in the galaxy. A typical galaxy may contain up to a few hundred globular clusters; our galaxy, the Milky Way, has somewhere between 125 and 200 globular clusters orbiting the galactic center. Most globular clusters are found in the large spherical halo of a galaxy.

My very modest photographic effort gives you a bit of an idea about all this. It's amazing what "every-day" digital cameras can do.

Saturday, July 22, 2017

This is why the Hubble Space Telescope (HST) exists.

Astronomers are constantly looking to get finer detail about the universe, in order to better understand  it's evolution. We are also trying to find "life as we know it" elsewhere, both on  planets and moons in our own solar system, and other planetary (exoplanet) systems. Traces which could be attributed to "life" are very hard to detect, and this effort requires all the details we can possibly gather. 

Optical and radio telescopes, underground particle, cosmic radiation, and gravitational wave detectors, and other ingenious devices constantly collect, and highly trained people analyze these data to come to some more detailed conclusions about the answers to these endeavours.

One of the major steps in acquiring more detailed information occurred when the Hubble Space telescope started collecting data in 1990. So far, it has sent back more than 1.3 million images, according to NASA. I don't think that any telescope on Earth has done so.

Below is an image I acquired via the half-meter remote-controlled telescope on the Canary Islands, and also downloaded a picture of the same globular cluster from the Hubble Space Telescope site.

The telescope is of a size which many amateur astronomers also have in their own, private observatories. The HST is a larger telescope which orbits Earth, its mirror is 2.4 meters across. The difference in the details is obvious. The telescope would show more detail if it were placed in orbit as well but not nearly as much, because of its smaller size. The reason for space-based telescopes is that this does away with all the interference caused by the Earth's atmosphere and man-made light and other pollution.

There are now other types of telescopes in space, most of which are dedicated to collecting data at wavelengths which are blocked from the surface of the Earth (ultraviolet, x-rays, deep infrared, certain radio frequencies, etc.).

All of this so that more details about the universe can be obtained.

M 53 imaged through a remote-controlled telescope

M 53 as seen by the Hubble space telescope, also remote-controlled 

Monday, July 17, 2017

Space is impressive

The Whirlpool galaxy
(click on image to enlarge)
 I took this image through a remote-controlled telescope on the Canary Islands. It can be seen as a small nebulous patch through binoculars.

Charles Messier, an astronomer who was an avid "comet hunter", generated a catalog of astronomical objects which, at the time and using rather smaller telescopes, could be mistaken for comets, because they appeared as faint and nebulous patches, just as comets do when they are far from the sun.

Charles Messier (Wikipedia)

These patches are listed from M1 to M110 in Messier's Catalog, and the Whirlpool galaxy is listed as M51. Messier did not recognize its shape. This spiral galaxy is about 25 million light years distant. The bright patch shown above M51 is what looks like the core of another galaxy (called a Seyfert galaxy), which seems to interact gravitationally with M51. This companion galaxy is listed in the NGC catalog as NGC5195. It was discovered in 1781 by Pierre Mechain and does not appear in Messier's catalog, although some astronomers list the pair as M51A and M51B.

The spiral structure of M51 was discovered in 1845 in Ireland by William Parsons (3rd Earl of Rosse) by means of a then giant 1.8 m reflecting telescope, called the Leviathan of Parsonstown - at the time the largest telescope on Earth. M51 was not recognized as a galaxy, separate from our own galaxy (the Milky Way), until Edwin Hubble (the Hubble Telescope in orbit around Earth is named in his honour) determined the distance of it. This distance puts M51 far outside the Milky Way and makes it a little more than one third as large. That still means that it probably contains about 150 billion stars. Edwin Hubble also determined that the universe is expanding, with far-reaching effects on cosmology and our general understanding of the evolution of the universe.

We know now of billions of galaxies - as numerous as the stars in our Milky Way. The Hubble Space Telescope shows that galaxies appeared very early in the existence of the Universe.

Impressive indeed.

Tuesday, June 27, 2017

Something Astronomical

Whenever our area experiences something less than a clear sky, it it still possible to take pictures of the deep sky by using a remotely controlled telescope. Here is my effort:

The Lagoon Nebula
(click on the image)

This nebula is a Hydrogen interstellar cloud whose dimensions are about 55 x 20 light years and which is about 4000 light years distant. It contains a star-forming region (the bright area) and can be seen with binoculars. The bright stars to the left are an open star cluster in the foreground. This image was taken through a half-meter remotely controlled telescope, located on the Canary Islands. Once downloaded, the picture can be enhanced by means of freely available graphics programs.

Under dark a dark sky, the nebula is an impressive sight, but you will not see the colours shown in the image. The human eye is not capable of showing colours at faint levels of light. That's why astronomy involves sometimes gigantic telescopes. If a telescope has a larger diameter it will collect more light. That allows subtle details to be detected, particularly if photography is employed. Photographs exposed for sometimes many hours will show colours and details undetectable by eye.

The best direct (i.e human eye) views of these faint objects are obtained under a dark sky, away from all the light-polluted cities.

Friday, May 19, 2017

A fragment from the solar system.

A couple of days ago (May 18) I set up my Canon 60Da camera to take a picture of one of the asteroids which orbit in the area between Mars and Jupiter. This is one of the first asteroids discovered (Vesta - by Heinrich Olbers on March 29, 1807). It is the first asteroid visited by the Dawn space probe and is around 500 km in diameter. You can find some details in Wikipedia,, and other websites.

I set the camera up on our back porch. The lens used was a 135mm Bushnell, which has an old Pentax mount. I have an adapter for the Canon digital camera, which makes the use of my old film camera lenses possible. The setting was at f2.8, ISO 800, exposure time 8 seconds, on an iOptron star tracking mount.

We live in a highly light-polluted area (near Metrotown) so some processing of the image was necessary. None-the-less, it's quite amazing what a digital camera can do under such poor conditions. Click on the top picture to enlarge it.

Asteroids are thought to be remnants of either an unformed planet or one that was broken up by some major collision during the planet-forming phase of our solar system. There are many thousands of such fragments. Some of them (not Vesta) occasionally impact Earth, with major consequences for life (it's happened before). Vesta is one of the largest. It looks tiny in the picture, because it was about 390,000,000 km distant from Earth at the time.

Here's a picture of Vesta taken by NASA's Dawn spacecraft:

Sunday, April 30, 2017

April showers

This month has been a month of generally lousy weather but also one of a reunion with longtime friends.

We spent about 10 days on a trip to Europe. The main reason was the planting of an American Oak tree in memory of our almost life-long friend Henry, who died one day before this past Christmas (see "Into the New Year" post). The planting took place in the town in which Henry was born (his family roots are deep and long in the community) in the same location where he played when he was a child. The ceremony was at once dignified, solemn, and funny. Many people of similar histories related anecdotes about Henry - he was never just an ordinary personality.

We have visited this town many times over the years and have gotten to know most of Henry's friends and family there. The memorial dinner in his honour took place at the local historic "pub" which has been in existence for many years in a building that is several hundred years old. Each of us had Henry's favourite drink (rum and coke) to start, and had a typically extended local dinner. It was a great occasion to talk to the people in attendance (there were about sixty and we know just about all of them). This was a typical European "wake".

We stayed with good friends with whom we have stayed several times before. Our host couple's son flew in on a surprise visit, much to everyone's delight. He lives in California (we have visited him and his wife there a couple of times, too). The whole time we were there a dinner party was laid on every evening, and sumptuous European breakfasts were part of every morning. There was also no lack of champagne, wine, and beer.

Therefore, the cold, blustery weather which persisted through all this time did not diminish the good time we had. The only downside relates to the way we travelled. We had booked our flight in the economy section (which should really be called the "sardines" section). On the way there, we had an empty seat in our four-seat row, which made this tolerable; on the way back, the plane was absolutely packed - for a ten-hour flight, that is next to torture.

Always a new experience...

Tuesday, March 28, 2017


This as been a somewhat unusual winter for our neck of the woods. While it has melted away now, snow stuck around for the better part of three months. The usual stretch is usually a few days, then it is replaced by rain. This month, after the melt, we have had only two sunny days so far, and temperatures have been below normal for almost the whole stretch.

You can see that this has put a severe damper (pun intended) on astronomical activities, and, at the moment, it looks as though this weather is going to continue for some time. In some way however, it has played into my personal plans anyway.

I've had, and have one more scheduled medical and dental routine appointments - none of which are debilitating in any particular way - the most unpleasant was the colonoscopy which I underwent a few days ago. This is a required routine check-up for me, in light of the death of our son Derek six years ago after dealing with colorectal cancer for more than four years. The routine itself requires a three hour hospital visit and is done under anaesthesia; you don't feel a thing, this is not the problem.  It is the preliminaries which are the unpleasant part. A day before the procedure you have to swallow some pills and two little bags of a powder which you mix into two litres of water. You cannot have any dairy products, solid food or red liquids, but are supposed to consume copious amounts of water, or bullion, clear soups, Jello, or other clear (non-alcoholic) liquids. By the end of the day, I felt thoroughly water-logged. All this in order to totally clean out your intestines, meaning that you are a constant visitor in the bathroom. There is no food or any liquid allowed on the day of the procedure until after it is done.

Today it's steadily raining again. At this time last year the cherry blossoms were in full bloom. This year, the trees are showing only a trace of pink. Some Spring.

Wednesday, February 1, 2017

Planetary Perspective

This month has been somewhat unusual for our area so far this year. The snow that started early in December has hung around until just a couple of days ago; there are still a few traces left. Yesterday and today have finally produced clear days. Last night a "cool" assembly of two planets and the Moon was visible in the evening sky (figuratively, and literally - temperature was near zero C at our place), and I took this picture:

Moon, Mars (above the Moon), and Venus - click on the picture to see a larger image.

You'll notice the "earthshine" outlining the part of the Moon which is not illuminated by the Sun. If you were on the Moon on the side which faces the Earth, the sun-lit Earth would have been a couple of days past "full Earth" in the Moon's sky, and would have been very bright. So we see that part of the Moon lit up by the sunlight which shines onto Earth, is partially reflected to the Moon, lights up the darker part of the Moon, and that reflected light is partially re-reflected back to Earth.

Earth passed Mars some months ago, so Mars is trailing, and will soon be on the other side of the Sun from the Earth's point of view, and Venus is moving faster than Earth towards its upcoming pass between the Earth and the Sun.

It's all a matter of perspective...

Tuesday, January 10, 2017

Into the New Year

Henry and Margarete, a couple who are our long-time friends of ours (they live in San Diego), some time ago invited us to spend New Year's Eve with them. We made the appropriate travel arrangements and looked forward to a sunny time away from the less than pleasant weather here (  - see December 2016 post). But instead of sunshine, we were presented with a rainy week. The weather and temperatures were like what we normally experiencing in winter here at home.

Unfortunately, the anticipated new year's party turned into a more somber affair. Henry died two days before Christmas and the party turned into a celebration of Henry's life. It was a bitter-sweet event, with about 90 people in attendance. We know most of them too, having visited our friends many times over the last 40 years or so. I had taken my wireless microphone kit with me to connect to the sound system in their house which I had modified for this purpose a couple of years ago. This turned out to be very useful for the reminiscences and anecdotes presented by many of his friends, along with singing and listening to some of Henry's favourite songs and music.

This turn of events happened twice to us last year. In April, instead of celebrating the 80th birthday of another close friend (whom I had known for 58 years) we also ended up celebrating his life - he died 3 days before his birthday ( - see April 28, 2016 post). This is not how we had planned to get together with friends last year.

We hope for a more joyful 2017.