Tuesday, May 22, 2018

First day in Sweden - transnational meeting

Finally our friends has arrived. A wonderful first day with presentations, group discussions and home economics. 

Wednesday, May 16, 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.

Cosmovisions. A Spanish present for our Swedish friends

The Spanish Erasmus+ team has studied the different Cosmovisions, with the help of the Philosophy teacher, Esther Gonz�lez.
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, J�tunheim, Nilfheim.

An eagle called "Ve�rf�nir" 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 J�nmundgander.


Tuesday, May 8, 2018

Work in Progress in Sweden

Building telescopes

In Gualdo Tadino, Italy

In Fuenlabrada, Spain


Plumbing material used for
the construction of the telescope:

  1. 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 

  1. 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:

  1. 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.

    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, May 7, 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. 

Total eclipse of the Moon.

Beautiful night to observe the sky with our telescopes or simply with binoculars. The total eclipse gave us wonderful images for our Erasmus...