Archive for the ‘planetarium’ Category

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Understanding astronomy enhances stargazing

November 16, 1985

The caller on the phone had just spent more than $1,000 on a used telescope. He had no success finding comet Halley, and after viewing several stars at high magnifications, wondered why anyone would be interested in astronomy. “What do amateur astronomers do anyhow?” he asked

My mind raced over the past 23 years of sky watching: the adventures of chasing eclipses, the hours spent making observations of Jupiter and the sun, the excitement of an 18-person meteor shower observation team, the whole planetarium career, telescope making, countless friendships, and I did not have a ready answer. I think I mumbled something about trying to develop an appreciation for who we were in relationship to the universe in which we live. I felt the answer was inadequate.

At the Manitoba Astronomy Club, an organization for those under 18 years, and operated out of the Manitoba Planetarium, we are trying to find good answers to that question.

In spite of the troubles of the caller, astronomy is available to everyone. Nightly, when the sky darkens, the great wonders are displayed for us to appreciate, or ignore. No one needs a telescope to see evidence of the monthly orbiting of the Moon, or observe the zigzag motions of the planets due to the earth orbiting the sun, or watch the changing altitude of the sun that causes the seasons, or see meteor showers and eclipses.

What the caller lacked, and what remains a barrier for most people, is a basic understanding of what is going on in the sky. When I have begun courses in astronomy, I have said that, if the sky is a dazzling and incomprehensible view of creation, then remember that feeling, because it soon will be replaced by something else: a sense of familiarity. It is ironic that we are part of the most sophisticated civilization that has ever existed on earth, and yet, as individuals, we seem to have lost touch with the night sky. Now we are dazzled by bright city lights, and the universe seems to pale in comparison.

My point is that basic astronomy is easy, it is fun, and the subject matter is always at hand. This is what the amateur astronomer has discovered. Once past this barrier, the hobby allows for a multitude of activities and explorations.

At MAC, we run a basic astronomy course once or twice a year so that everyone there is able to pass that barrier and get on with the neat stuff. For instance, there is a lot of attention being given to Comet Halley right now. That is largely because of its celebrity status. While it will be a very good comet, for amateur astronomers it is the third or fourth comet that they have seen this year.

Astronomy is not just a nighttime affair. One of the most interesting celestial objects to observe is the sun. It is large and bright, and therefore easy to observe with the smallest of telescopes. It also is very active, with sunspots that appear and vanish. Because of the brilliance of the sun, it also requires some knowledge to observe — the sun’s rays can blind the careless, and damage the improperly used optical equipment.

Teaching

Teaching introductory astronomy courses has made me aware of three things. First, how simple the concepts of astronomy are. The difficulty that some experience seems to be the fact that, for most of us, all of the information is completely new; it is removed from our previous experience. Second, much of the course consists of just becoming familiar with the constellations, and the catalogue of astronomical objects. Learning this leads to many other insights. And finally, familiarity with the cosmos does not breed contempt. It does enrich ones life, and allows the amateur astronomer to participate in the drama of a science that is always facing a new frontier of potential discoveries.

There is one sure way to pass through the initial barrier. Join one of the two local organizations of amateur astronomers: MAC or the Royal Astronomical Society of Canada, Winnipeg Centre; and make astronomy a hobby.

What you will find is that astronomy is not one hobby, it is a multitude of avocations.

Astronomy allows several hobbies and abilities to be combined. A knowledge of cameras and darkroom techniques is most useful if you decide to try astrophotography. A machinist can make every component and accessory for a telescope, and it is not uncommon to find a lathe in an astronomer’s basement. Every astronomy club needs people who have skills in accounting, organization, and teaching.

My telephone caller had expected the telescope to show him the universe. He had looked at some stars, and all he saw were some spots of light made brighter by the optics.

In case I have given the impression that observing plain stars is boring, I will admit that this is sometimes true.

Alberio

But I would love to show you a certain star In the constellation of Cygnus, called Alberio. It looks like one star to the unaided eye. The telescope reveals it to be two stars. They are beautiful. This is really a solar system with two suns. One sun is shining with a golden light, and the other is a steely blue. The imagination can conjure up fantastic scenes of the interplay of light on a planet that might circle one of those stars.

In 1985 Robert Ballantyne was director of the Manitoba Planetarium. His weekly column in the Winnipeg Free Press, called Sky Watch, focused on the return of Comet Halley.

© 1985 Robert Ballantyne and The Winnipeg Free Press

Sky Watch - Robert Ballantyne | Winnipeg Free Press

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Star-gazers plan Halley night

November 9, 1985

COMET HALLEY IS IN THE sky. It is moving noticeably among the stars from night to night. Since we first saw it in August, local observers have watched it become transformed from something so faint that it was barely perceptible in the biggest telescopes, to a hazy ball of light that is visible in a midsized amateur telescope. One especially sharp-eyed person reports that she could easily see the beginnings of a tail on the comet.

If you do not have a telescope, you will have your first chance to see Comet Halley next Friday night.

Comet Halley Sky Watch #1 will take place at the Mennonite Village Museum, just north of Steinbach, between the hours of 7:30 p.m. and 11 p.m. Admission is free.

Very often, when the public is invited to look through telescopes, they do not have the opportunity to learn exactly what it is that they are seeing. The wonder of the telescope is not that it shows beautiful views of the universe — often the objects seen are faint and indistinct, and certainly not self-explanatory — but that you can see real things that populate our galaxy. When we can understand what it is that we are seeing, we can begin to develop a sense of who we are, and how and where we fit into this universe. For this reason, Comet Halley Sky Watch #1 will have an indoor program to explain something about the telescopes, to give some background on Comet Halley, and to talk about some of the other interesting things in the sky. Because of the indoor program, Comet Halley Sky Watch #1 will take place even if there is a cloudy sky.

Several organizations are combining forces to give us this early look at Comet Halley: the Manitoba Planetarium of the Manitoba Museum of Man & Nature, the Royal Astronomical Society of Canada (RASC) — Winnipeg Centre, The Manitoba Astronomy Club (MAC), and the Mennonite Village Museum. Each is providing volunteers to make the event happen. For a long time we have known that Nov. 15 would be a special observing night for the comet. As you may know from reading these articles, the best time to view a faint object, like the comet, is when the moon is not around. Therefore we seem to have a series of good observations once a month during the dark of the moon, and then we have to wait while the moon goes by; and the next month we are back out to see what has happened.

Moon waning

This past week the moon had been waning away in the early morning sky. On Tuesday there is a new moon, which means that the moon is so close to the sun in the sky that you will not see it. For the next two weeks, the comet observers will be out with their telescopes.

Incidentally, and this has nothing to do with the comet, at the time of the new moon, there will be a total eclipse of the sun. If you want to see it, the best place for viewing will be north of the Ross Sea on the coast of Antarctica. I know that it will be spectacular, and I wish I could be there.

The other thing that makes next Friday special is that it is the first of three days during which Comet Halley will be sliding past a very prominent star cluster called The Seven Sisters or The Pleiades. This means it will be very easy for everyone to look up in the sky and know exactly where the telescopes are pointing.

In addition to observing the comet, Comet Halley Sky Watch #1 will have telescopes trained on a number of interesting astronomical objects. The Pleiades look stunning in small rich-field telescopes. It is a galactic star cluster, a group of stars which are all young and hot. They were born together from the same dust cloud and they are continuing to move together through space. There are several beautiful clusters in this part of the sky.

This is the best time of year to observe the Great Galaxy in the constellation of Andromeda. This vast whirlpool of stars is the giant in the local group of galaxies, and If you have good eyesight, it is the most distant thing you can see without a telescope. It is one of those objects that does not look impressive, but when you understand what you are seeing, it is awesome.

Jupiter is the brightest star-like object shining in the southwestern sky lately. Because of its churning atmosphere and its family of moons, it’s always an interesting sight in a telescope.

Astronomy buffs

Free Press caption: Powerful scope is essential for astronomer Ballantyne

Powerful scope is essential for astronomer Ballantyne

If you have ever thought you might be interested in astronomy as a hobby, or if you have been considering buying a telescope, Comet Halley Sky Watch #1 will, give you the chance to meet people who love the subject and have considerable experience. Both the Royal Astronomical Society and the Manitoba Astronomy Club will have tables set up to explain what they are all about. The RASC accepts membership from anyone with an interest in astronomy over the age of 16. MAC is associated with the Planetarium and its members are all under 18. In addition to looking through the telescopes, be sure to ask the operators about the size and nature of their ‘scopes, and then compare with the others. Consider cost and convenience as well as the optical excellence of each.

Folks in Thompson can see the comet Friday Nov. 15 if the sky is clear. Bill Taylor will have a program at Eastwood School, with a movie at 7 p.m., followed by viewing of the comet through an eight-inch (20.32-centimetre) telescope. If the weather is cloudy, the viewing may be rescheduled

In 1985 Robert Ballantyne was director of the Manitoba Planetarium. His weekly column in the Winnipeg Free Press, called Sky Watch, focused on the return of Comet Halley.

© 1985 Robert Ballantyne and The Winnipeg Free Press

Sky Watch - Robert Ballantyne | Winnipeg Free Press

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New discoveries help Planetarium design comet model

October 26, 1985

ASTRONOMERS LOVE TO DESCRIBE nature in terms of numbers and mathematical formulae. At the planetarium, we look at all of this and say, “Yes, that is all very interesting, but what does it look like?” A planetarium has to be able to show it. The question is simple, but it can produce some interesting results.

Because it is small and well concealed inside the atmosphere, or coma, of the comet, the nucleus of Comet Halley has been the invisible author of the great celestial show that we see every 75 years.

When it returns

In the new planetarium program, The Comet Adventure, producer Bill Peters wanted the show to illustrate what it might be like as the first humans land on the icy heart of Comet Halley, when it next returns in the year 2061. Artist Ed Barker had to find the answer to “what does it look like?” Everyone imagined that, because the comet is icy, the surface of the comet would present a miniature Arctic scene.

The first clue that this concept might be misleading came from some of the new research that was done on Comet Halley early this year. Astronomers made a series of infrared measurements with the three-meter NASA infrared telescope facility, and the 2.2-meter University of Hawaii telescope on Mauna Kea, in Hawaii. Surprisingly, they were able to announce the approximate color of the comet’s nucleus.

At the beginning of 1985, the comet was close enough to the sun that its heat was starting to evaporate some of the surface ices to produce the coma. There was a short period between the time when the nucleus was close enough, and bright enough to observe, and the point when the nucleus vanished inside the growing coma.

The astronomers measured light from the nucleus through filters at different wave-lengths, and were able to deduce that they were looking at a very dark reddish object. The astronomers said “No comet observed by us has a color consistent with clean ice.” This was exciting new information.

For dramatic reasons, we wanted the surface of the comet to be an active place. The next piece of startling evidence was collected during the 1910 passage of Comet Halley, although the researchers at the time did not know what they had found.

Photographs

In Arizona, planetary astronomer Stephen Larson has been re-working 1910 photographs of Halley using a computer to enhance some of the features. As a result, Larson has been able to derive the speed of rotation of the Comet, as well as the orientation of its spin axis.

For our show, we discovered the surface of comets could be very dynamic. Warmed by the sun, the gases do not simply evaporate from the surface of the comet like snow on a sunny day. Larson’s pictures show violent jets of material being spewed into space.

Bill Peters and Ed Barker work on planetarium comet model special FX

Recent discoveries aid Planetarium staff in making comet model

Barker decided to illustrate the changes that take place on the surface on the comet by building a model of the surface. We use full-circle photography of the model to put the audience right in the scene.

He began with Styrofoam on a doughnut-shaped table that was 5-1/2 feet in diameter. It had a two-foot hole in the centre for the camera. For days Baker worked with a hot-wire Styrofoam knife to sculpt the fantastic surface of the comet as it was when it was as far from the sun as planet Jupiter. This is the point when the sun is just beginning to transform the sleeping comet from the little ice world that has remained unchanged since it headed out of the solar system in 1986, to the fuming giant that will shine in earthly skies In 2061.

Acrid smell

When the acrid smell of burning plastic faded, Barker was spraying, dabbing, and brushing the surface with a palette of colors, especially reds. Carborundum and barnsite (grit) were worked into the surface for texture. And finally, he added a dusting of stucco sparkle to provide reflections from the comet’s crystals.

The Fred Whipple, a comet-lander spacecraft, was added to the scene and photographed. Immediately, Barker attacked the surface of the comet with the hot-wire knife, lopping off icy spires, and opening up fissures where special-effects projectors will allow great jets of gasses to vent into space. This is the comet at its closest approach to the sun. Four scenes use this model. When we last see it, there is a light frosting of ice crystals caused by some of the coma freezing to the surface of the comet as it begins another 75 year Journey away from the sun.

At the planetarium, we will be interested in all of the new information that will be discovered about Comet Halley in the coming year. We particularly will be intrigued to see if there is anything that will indicate how accurate we are with our images of the comet’s nucleus.

In 1985 Robert Ballantyne was director of the Manitoba Planetarium. His weekly column in the Winnipeg Free Press, called Sky Watch, focused on the return of Comet Halley.

© 1985 Robert Ballantyne and The Winnipeg Free Press

Sky Watch - Robert Ballantyne | Winnipeg Free Press