Sunday, 27 May 2018
Friday, 25 May 2018
Tuesday, 22 May 2018
First day in Sweden - transnational meeting
Finally our friends has arrived. A wonderful first day with presentations, group discussions and home economics.
Wednesday, 16 May 2018
Telescopes and star maps. Studying the sky in Fuenlabrada
Once we made our telescopes and worked with the star map, we observe the sky in April, the 19th. We could see the Polaris, Canis major, Orion, Ursa minor and Ursa major, and some planets, like Venus, placing them in our map.
We also used the Stellarium in class to compare the sky in the three points: Gualdo Tadino, in Italy, Eskilstuna, in Sweden and Fuenlabrada, so to as determine if there were little or big differences.
We project the sky in May, the 24th in order to know if we could see the stars being so close of the North Pole. That is the problem: the most dark hour would be betwen 24:00 and 1:00 more or less.
Worldviews. A Spanish present for our friends
The Spanish Erasmus+ team has studied the different Worldviews, with the help of the Philosophy teacher, Esther González.
This is the first task in relation to the humanistic part of the project, approaching the myths and legends about the universe.
For the nordic people universe was divided in 9 kingdoms which were located in a huge tree called Yggdrasil. These kingdoms were Asgard, Midgard, Helheim, Nidaveir, Alfheim, Musspelheim, Vanaheim, Jötunheim, Nilfheim.
An eagle called "Veãrfönir" lived on the top of Yggdrasil while a dragon called Fafnir slept in the roots.
In its branches there were a deer called Eikbyrnir and the squirrell Ratatosk.
Also, there was a big snake curled in Midgard's sea called Jönmundgander.
This is the first task in relation to the humanistic part of the project, approaching the myths and legends about the universe.
For the nordic people universe was divided in 9 kingdoms which were located in a huge tree called Yggdrasil. These kingdoms were Asgard, Midgard, Helheim, Nidaveir, Alfheim, Musspelheim, Vanaheim, Jötunheim, Nilfheim.
An eagle called "Veãrfönir" lived on the top of Yggdrasil while a dragon called Fafnir slept in the roots.
In its branches there were a deer called Eikbyrnir and the squirrell Ratatosk.
Also, there was a big snake curled in Midgard's sea called Jönmundgander.
.
Tuesday, 8 May 2018
Building telescopes
In Gualdo Tadino, Italy
In Fuenlabrada, Spain
Plumbing material used for
the construction of the telescope:
- Galilean telescope with convergent lenses in the
objective and the ocular.
●
50mm diameter PVC pipe.
●
Joint for pipe
of diameter 50 mm.
●
Female joint
sleeve of 50 mm.
●
Male cuff of 50 mm.
●
50-25 reduction cup.
●
25-20 reduction cup.
●
Converging lens
of 1000 mm focal length and 50 mm in diameter.
●
Converging lens
of 44.4 mm of focal length of 22 cm in diameter
- Galilean-Kepler’s telescope.
Achromatic doublet lens in the
objective and ocular ramdsem.
●
40 mm diameter PVC pipe.
●
25 mm diameter PVC pipe.
●
Joint for pipe
of 40 mm.
●
Joint for pipe
of 25 mm.
●
Female joint sleeve
of 40 mm.
●
Male cuff of 40 mm.
●
32-25 reduction cup.
●
25-20 reduction cup.
●
Achromatic doublet
of 286 mm of focal length and diameter 40 mm.
●
Two converging
lens 59 mm of focal length of 22 cm in diameter.
(Following the instructions done in this
link:
- Galilean telescope.
Objetive with converging lens and ocular with
diverging lens
●
50 mm diameter PVC pipe.
●
Joint for pipe
of 50 mm.
●
50-25 reduction cup.
●
25-20 reduction cup.
●
Male cuff of 50 mm.
●
Female joint
sleve of 50 mm.
●
Converging lens
of 1000 mm focal length and 50 mm in diameter.
●
Diverging lens
of -66mm focal length and 25cm in diameter.
General guidelines to build a home-made
refractor telescope
1.) The first
thing we have to consider are the lenses that we have, because they determine
the quality of the image the telescope increases and its dimensions.
We have to
consider two characteristics:
a) The diameter of the objective which will
mark the opening (the amount of light that the telescope can collect).
b) The focal distances of the objective and
the ocular.
The quotient:
focal distance of the objective is called focal relation. For values lower than
6 we get a very distorted image, with a bluish halo around and they are
difficult to build.
It is
recommended a value of ratio higher than 8.
The quotient:
focal distance of the objective determines the number of increases.
It is
recommended not to exceed twice the increases of the opening because the image
can be distorted and it would get blurry.(If the diameter is 50 mm the
increases have to be less than 100 mm)
2.)
If we don’t know the focal distance (or if we want to check them) we can
go to an optics to measure the diopters.
DIOPTERS = 1 / FOCAL DISTANCE (in meters)
3.)
Known the lenses diameters and their focal distances, we can set the
distance between the lenses and the diameter of the tubes.
-
The lenses have
to be separated at a distance that will be the sum of the focal distances.
-
The tube’s
diameters are the same to the lenses diameter (or from the diameter of the
eyepiece we introduce reductions until the eyepiece diameter).
4.) Once
we know the lenses distance, we calculated the length of PVC tube or tubes.
To the length
between the lenses, we subtract the lengths of the pieces that we adapt to the
main tube.
5.)
We cut the PVC to sice, we sand them, paint them black on the inside
with a spray and let dry.
6.) We fit the lenses and parts and we
check that the telescope is working properly. If it doesn’t, we have to correct
the length of the tube.
7.) Made adjustments to attach parts (with
glue, tape…) and decorate with our project logo.
8.) We complete the process by making a
solar filter. To do this, we cut out two rings of cardboard with the diameter
of the tube and a circle of the solar filter that we previously bought. We
paste the two rings, one on each side of the filter circle. Let it dry and
check that it fits well on the end of the telescope tube.
Monday, 7 May 2018
Activity: School's Astronomical Observatory, Gualdo Tadino
DATE: the 26th April
2018 at 10 PM
1st Step
- general observation of the sky with the naked eye,
identifying Venus, the Moon (clearly visible towards the south, 4/5 lit up) and
the Big Dipper star constellation. The Moon and Venus were observed also with
the Galilean telescope.
2nd Step
- observation of the Moon through the telescope of the
observatory
- we saw the craters along with the depressed and raised
areas.
- when it got darker
we got to identify the North Star with the naked eye.
- at about 10.30 pm Jupiter rised, towards south, it was so bright that it was clearly visible
with the naked eye.
3rd Step
- the technician gave
us directions to map the star chart: he has recommened us to observe with the
naked eye for more nights in a row (at least 3-4, 30 minutes each) in order to
train the eyesight for the night sky observation.
After a few
observations, the students will then be able to place the North Star on the
chart, the stars of the Big Dipper, along with other bright stars and planets,
that they will have to find by referring to other star charts already existing
(such as Stellarium app) referring to our present time and location.
Thursday, 3 May 2018
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