Astronomy
Travelling with a telescope
As I wrote in my motivation page, I am
travelling around the world on a motorcycle carrying a small telescope.
I want to give an opportunity for kids all over the world to experience the sky
through a telescope.
The telescope I am bringing with me is a small Newtonian reflector telescope,
named for Isaac Newton who first pioneered this concept. This type of
telescope uses a tube, open at one end, which will be pointed to the sky.
At the other end is a mirror, which collects the light that is coming from the
stars or planets through the opening and focuses and reflects it towards
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A Newtonian reflector telescope. The incoming light is focused by the primary
mirror and reflected 90° to the side where it can be viewed through a lens.
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another mirror, suspended close to the opening within the tube. This is the
secondary mirror and it's purpose is to deflect the light to the side, so that
it can be viewed without obstructing the opening of the telescope.
Another small tube is then attached to an opening in the side, where the light
from the telescope will be focused. This is where different lenses, known
as eyepieces, are now used to magnify the image and allow to see the area of
the sky where the telescope is pointed at. Remember to NEVER point a telescope,
binoculars or look directly at the sun.
The sun radiates a tremendous amount of energy and a direct exposure can
damage the eyes irreversibly. The sun is also the brightest object in the sky.
The telescope's main mirror,
which will determine the maximum amount of detail that can be seen, is
four and half inches in diameter. Despite the fact that this is small for
a reflector telescope, it is as big as I can realistically carry on my
motorcycle. However, this is enough to allow good views of the moon, the
stars, some galaxies and nebulae, and even resolve some detail on the planets.
The degree of magnification is determined by a combination of the
telescope's focal length, which in my case is 500 mm, and the eyepiece.
E.g. with an eyepiece of 20 mm, the magnification is
500 ÷ 20 = 25×.
The maximum practical magnification is limited by the telescope's
aperture, or how much light it can collect. A rule of thumb is 60×
magnification per inch of aperture, yielding a maximum practical magnification
of 270×, which is more than enough for a number of objects.
The telescope tube will be mounted on a sturdy aluminum tripod attached to
an equatorial mount. This type of mount is quite heavy, but provides for a
better viewing experience when showing objects in the sky to groups of people, as the construction of the mount allows the telescope to track the natural
motion of the sky.
Great! How can I schedule a demonstration?
Well, first of all have a look at my current location
and where I'm heading in the near future. If you don't see your town or
country, look at my planned route for where I'm
expected to be. If all of this doesn't help, please send me a
message and ask me if I
can help. My planned route is not etched in stone and making a deviation of
a couple of hundred kilometres (or even thousands) is entirely possible
and might even be desireable.
Once you determined that I'll be heading your way,
contact me and we can
schedule an observation of the sky using the telescope, or if you prefer
I can also just give a presentation about astronomy (this might be the only
choice if it's raining or cloudy).
For an observation of the sky with the telescope, you need to be aware
of a few basic requirements:
- A telescope is really only useful after dark, so the time for
observing will have to be scheduled between sunset and sunrise.
The time also depends on which particular object you might want to
observe, e.g. Jupiter might only rise after 3am at your location.
- Let me know if you want to observe a particular object in the sky,
like Jupiter for instance, and
I will then check if it will be possible
and at what times. On the other hand, you can also let me select
a few interesting objects for the scheduled observing time.
- Make sure that everyone can be up at the time you want to schedule
an observation, i.e. will the parents allow the kids to see Jupiter
at 3am? It will probably be easier to schedule observations for after
sunset and not to prolong them too long.
- As much as I'd like to show the telescope to hundreds of kids, having
too many people in a group will make the experience less enjoyable,
because there is then a lot of waiting. Remember, it's dark and it
might also be cold.
- Talking about cold, everyone should be dressed for colder than it
actually is. When standing or sitting in the dark and cold for minutes
or hours (yeah, right, when do kids sit still for that long), it can
be quite cold. Even in the middle of the summer.
- As you know I'm probably travelling for the first time to your city
and I don't know the area, so it's very helpful if you can select a
place that is both safe and does not have too many city lights that
might interfere with the viewing. You don't have to select a spot
in the middle of nowhere, sometimes even the schoolyard can work
as long as any nearby lights don't illuminate the area. A worse problem
is the illumination of the sky by city lights, so if you're in a village
it might actually be good, even with nearby lights.
- Now that I mentioned lights, you may bring flashlights with you,
specially for the part when I am explaining how the telescope works.
But during the time of observing the sky NO flashlight should be
allowed, because people need time to adapt their eyes to the nightsky.
Using a white light would reduce the pupil again and waste time
(because you need several minutes to achieve a good night vision).
However, I will be using a red bycicle light and you can use a similar
red light or cover the flashlight with red celophane. A red light
affects the pupil less.
- If it rains or the sky is particularly cloudy, then there isn't
really much to see in the sky and the event would have to be postponed.
- Well, this whole website is in english and portuguese and we speak
spanish. How are we going to understand? I don't know (that's helpful!).
I do speak english, portuguese, german and some french. As any
portuguese speaker will attest, I can understand spanish (I'll see about
that!), but I don't really speak it. And for all other languages I'm at
your mercy. So, if the language might be a barrier, it would help if at
least someone spoke one of the languages I speak.
Besides observing the sky with a telescope, I can also give a small
presentation about astronomy, using my laptop computer. To do this, the
best would be to have an LCD projector available (I don't have one) or a
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The earth as seen from Apollo 17,i
returning from the moon in 1972 (NASA)
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computer monitor. If none of these is available, I can also show the
presentation directly on the laptop. It would also be a good idea to have
an electrical outlet, as my laptop doesn't have a battery (I bought it
used). The presentation is basically a collection of images of our universe.
So, send me a message
and I'll be glad to setup an observation session with the telescope or
a presentation.