( fichero pdf guiadidactica.pdf 2.36 Mb )DIDACTIC GUIDE

the moonJust as the literature allows us to understand how people lived a certain time, in works of art is also possible to trace the beliefs and lifestyles of the past. For example, since the days of ancient Greece it was believed that the moon was a perfect sphere which surface was highly polished. Hence that our satellite was considered as a symbol of purity and was frequently represented at the feet of the Virgin. However, early in the 17th century, Galileo first observed the moon with the telescope, and found a landscape of valleys, craters and mountains that cover our own planet. His drawings show unequivocally the imperfect nature of the Moon.

 

 

 

Here are two Madonnas with a moon at her feet, one painted by Murillo and another by Cigoli. Would you know which one is more »realistic» in the astronomical details?

madonne

Do you know any work of art - however popular - regarding the scientific and technological advances of the 20th century? Can you find a famous painting where appears an airplane? And a locomotive?

In the first sequence of the program Urania shows to her friends some examples of art works that incorporate elements related to astronomy. The Prado Museum website allows to enjoy these paintings in great detail. Can you identify all the elements mentioned in the speech and reproduced here?

  • The seven liberal arts

    The seven liberal artsEach one is represented by a woman who appears accompanied by the most important figure in the discipline. Astronomy heads the composition carrying a celestial sphere. Sitting at his feet we see Ptolemy, who between the first and second centuries collected in 13 volumes the history of Greek astronomy.
    Museo del prado: The seven liberal arts

  • Sight

    sightThis work belonging to the set of the Five Senses is the result of the collaboration between Rubens and Jan Brueghel “the Elder”. It was painted in 1617 and, to our knowledge, is the second painting of history in which appears a telescope.
    Museo del Prado: Sight

  • Saturn devouring his son

    Saturn devouring his sonRubens also painted his own version of the classic myth about the god Saturn. I would like to draw attention to the top of the box, where a triple star represents the planet Saturn as Galileo Galilei had observed 26 years earlier.
    Museo del Prado: Saturn devouring his son

  • Rubens painting the Allegory of Peace

    Rubens painting the Allegory of PeaceTo the right is Mars, dressed as a warrior, harassing Venus, symbolizing peace. And at the bottom, some of the objects that are destroyed by war. These include an astrolabe and an armillary sphere, representing scientific knowledge.
    Museo del Prado: Rubens painting the Allegory of Peace

Internet and some applications such as Google Earth or Google Maps allow you to make a virtual trip to some of these places and check, for example, its orientation with respect to the cardinal points. Find some pyramids in Egypt, and also in Central America. Are they oriented in any special way? Is that orientation perfect or just approximate?

As Saturn reminds us at a certain point of the program, Christian churches also tended to be oriented with respect to the cardinal points. Find with Google Earth the main Spanish cathedrals (Santiago, Leon, Burgos, etc..) and check their orientation. What about other recently built cathedrals, like the Almudena in Madrid?

plaza maria pitaApart from the religious monuments, many civilian buildings are oriented to the cardinal points. Does it happen as well with the city council of your town? What about the football stadium or hospitals?

The orientation of the axes of the Plaza de María Pita, which houses A Coruña City council, matches up with the cardinal points.

 

The names of many stars and constellations, reveal their Babylonic, Greek, Roman, or Arabic source. Would you know the origin of stars like Sadalmelik, Capella, Kornephoros, Polaris, Ukdah, Bellatrix, Mirfak or Tsze Tseang?

The constellations are arbitrary groupings of stars that throughout history have been associated with the figure of an animal, object or mythological being. In general, each culture has imagined its own, but some are repeated suspiciously as far as ancient Greece or the Amazon jungle.

The sky map currently consists of 88 constellations that cover the entire sky like a mosaic. Some are easy to recognize, as the Big Dipper, Orion and Scorpio. Others, however, have little shining stars to help us locate them. The best tool to learn to know the sky is a planisphere. There are several computer programs that allow you to identify what you´re watching. One of the best is called Stellarium (www.stellarium.org) and is free.

If you have a smartphone, for very little money you can download an application of augmented reality as StarWalk. Placing the phone as a window frame the application will tell you what you are watching.

Astronomy is one of the oldest sciences, even though because deciphering the movements of the stars helped the first civilizations to oriented on trips, and develop schedules that allowed them to organize their activities. Moreover, almost all cultures turned their mythology and beliefs in the sky, and many of them left a sediment that can still be tracked, for example, names of stars, planets and constellations.

The planetarium program talks of a virtual reality machine that allows you to visit some historic places in which it is still possible to feel the weight of astronomical knowledge.

  • The cave paintings of Lascaux

    We are in the cave of Lascaux in France. As you can see, is decorated with magnificent prehistoric paintings. Some researchers argue that in this veritable Sistine Chapel of Paleolithic Art is the first representation of the Pleiades.
    www.lascaux.culture.fr

  • The Stonehenge cromlech and the Almendros cromeleque

    On the summer solstice, the sun rose across the central axis of the building. It’s... let’s say, amazing that 5000 years ago they had such precise astronomical knowledge.
    wikipedia: Cromlech

  • The antas or dolmens of Alentejo

    The study of more than a hundred of these dolmens has revealed that are oriented at sunrise - or perhaps at the moonrise - sometime in the annual cycle. Plates with numeric patterns have also been found and suggest that the builders relied on astronomical observations to measure time.

  • The petroglyphs on the Northwest Iberian Peninsula

    The Great Deer at Laxe dos Carballos and other petroglyphs found in Pontevedra, northwest of the Iberian Peninsula, seem to confirm this lunisolar calendar.

  • The pyramids of Giza

    At the plateau in Giza, near Cairo, we can see the famous pyramids of Cheops, Chephren and Mycerinus, which are perfectly oriented to the four cardinal points.

If these questions have made you uncomfortable, don´t worry. The first experiment that showed unequivocally the Earth´s rotation was made by Leon Foucault, who swung a pendulum similar to that now hang in many planetariums and science museums. If you have one nearby, you can see how it works and what it shows on the website of the Science Museum of Valladolid.

 

 

Didactic files: Foucault pendulum

Starry Night at the Museum contains several sequences in which we can observe the movements in the sky at night. Although the presence of so many stars can lead to confusion, the fact is that the motion of the sky is very similar to the sun during the day. And both have their origin in the rotation of the Earth, that completes one turn on its axis within 24 hours.

 

Today we take for granted that the earth turns endlessly, but if you think about it, we don´t have ample evidence that the movements of the stars are the result of Earth´s rotation. Do you notice a steady wind blowing from the east? In fact, until a few centuries ago everyone believed that the Earth - as it seems - was motionless, and the planets and stars turned around it. Can you think of any observation or experiment that demonstrates indisputably that the earth rotates on itself? If you do not have evidence, why do you think we´re so confident that the Earth rotates on itself and around the sun?

 

Given that our planet is roughly spherical and has a radius of about 6350 km, calculate the distance covered during a day by an earthling who is on the Ecuator. How fast does this movement mean? And if we calculate the speed at which we move because of the (hypothetical) annual movement of translation of the Earth around the Sun? Is it possible that we are moving through space at more than 1000 km / h? And if so, why don´t we perceive it?

The poor quality of Galileo´s telescopes is evident in these pictures of what he saw when focusing on Saturn. Today we know that the planet is surrounded by a ring system, but Galileo could only distinguish a sort of "ears" flanking it.

saturn

The first telescopes were made up of sets of lenses, but imperfections degraded the image as the light passed through. In addition, the search for magnifiers resulted in increasingly long tubes, so that came to be unmanageable.

Another of the great names of science, Isaac Newton revolutionized the construction of telescopes using curved mirrors instead of lenses. As the light reflects off them without crossing the image degradation is lower. In addition, the scheme with mirrors allows the building of compact telescopes.

telescope

In order to obtain the best images, the large telescopes are now being built in places where the sky quality is exceptional. The most important are grouped in the Canary Islands, on the peaks of Hawaii and in the desert of Chile. What do these places have in common? How do they look in photographs showing the city lights at night?

night map

The relationship between science and technology is complex. Sometimes a scientific discovery is an unexpected application on a new technology. But sometimes we need a technological breakthrough to open the door to new scientific discoveries. This is what happened, for example, with the construction of the first telescopes in the early seventeenth century. Galileo produced some of the first, and although their quality was far below cheap binoculars, they allowed him to see things that nobody had seen before. And best of all is that anyone can see his main observations in a clear night.

For example, he realized that the Milky Way and some nebulae that patched the sky are nothing but a multitude of small stars, too weak for our eye to distinguish them individually.

Milky Way

Just as the telescope allowed him to see stars too faint to the eye, it also put within reach the four brightest satellites of Jupiter. These bodies are not distinguished from the stars above, except that they seem to follow the planet as a slow stroll through the constellations of the zodiac. Galileo knew that Jupiter was much closer than the stars, which meant we could see those stars that change position during a single night, were actually the satellites of Jupiter.

jupiter

He also noticed that the line separating the illuminated area of the dark regions of the Moon is not a perfect curve -as would be expected if the moon was a sphere- but a broken line that demonstrates the existence of ground features.

the moon

Light pollution is not only a problem for astronomers. Many species of animals -including humans- are altered in their behavior by the disappearance of nocturnal cycles. But also, if we consider that the light projected upward is wasted light, and that most of the electricity we use comes from power plants that burn fossil fuels, we can imagine the magnitude of the environmental problem. In light of these considerations, some have even said that these images of nighttime light sources are more than a map of the distribution of human population and wealth, a map of the human stupidity and waste. What do you think?

 

After observing a dramatic sky crossed by the Milky Way, the naked Maja sighs and remembers a poem that Jose Asuncion Silva devoted to the stars. Here´s the full version:

Interrogación (?...)

 Estrellas que entre lo sombrío,
de lo ignorado y de lo inmenso,
asemejáis en el vacío,
jirones pálidos de incienso,
nebulosas que ardéis tan lejos
en el infinito que aterra
que sólo alcanzan los reflejos
de vuestra luz hasta la tierra,
astros que en abismos ignotos
derramáis resplandores vagos,
constelaciones que en remotos
tiempos adoraron los Magos,
millones de mundos lejanos,
flores de fantástico broche,
islas claras en los océanos,
sin fin, ni fondo de la noche,
estrellas, luces pensativas!
estrellas, pupilas inciertas!
¿Por qué os calláis si estáis tan vivas
y por qué alumbráis si estáis muertas?...

The beauty of the sky has inspired musicians, poets and painters. Can you find at least three works in which the night, the planets or the stars play a special role?

One of the most exciting sequences in the program is the night observation starring a group of amateur astronomers. In Spain there are many astronomical groups who enjoy this hobby and work with professional scientists gathering and analyzing data. They also tend to be the ones who discover the comets and maintain a constant activity to bring astronomy to the general public.

 

The website of the International Year of Astronomy maintains a list of astronomical groups in our country. Locate the nearest and contact them to try to arrange a chat or better an astronomical observation for beginners.

 

The greatest enemy for amateur astronomers, is not cold or sleep, but light pollution. The lights of cities and roads minimize darkness, and prevent to see less bright objects. In the program you can see how the situation annoys Saturn:

In my time the Milky Way, the stars and planets could be seen anywhere. But today, with all the streetlights in the cities we have to go to the boonies to find a dark sky. What’s wrong with these people? Are you now afraid of the night?

Where are the stars? And even worse, some believe that lighting up the night like day is a sign of progress and modernity. How thick!

The program cites the Declaration in Defense of the Quality of the Night Sky and the Right to Observe the Stars. You can find more information about this initiative at the Starlight project website.

 “The right to an unpolluted night sky that allows the enjoyment and contemplation of the firmament should be considered as an inalienable right of humanity, comparable to other environmental, social and cultural rights”.

What other statements on intangibles do you know? Do you agree on the preservation of such cultural heritage?