Measuring the Skies: From Tartu to the End of the Universe
April 27, 2016 – September 30th, 2016
The universe we know has two important measures—time and space. Nowadays, most astronomers agree that the visible universe is 13.8 billion years old and its diameter is 28 billion parsecs or 91 billion light years. How do we know that? The science of astronomy is at least 5,000 years old. Astronomers have been able to use telescopes only for the last 400 years. Constellations, solstices and equinoxes, celestial coordinates, laws of planetary motion, approximate distances in the solar system were already known before the invention of the telescope. Increasingly larger, better and more precise telescopes enabled astronomers to map and measure more and more distant celestial bodies. Astrographs—special devices used for photographing the starry skies—used photography to catch more light on glass plates and brought us messages from even more distant objects. Astrophysicists found a way to extract the secrets of the celestial bodies’ movement and composition from their spectrum. From there, they moved on to what was invisible to the human eye. In 2016 they managed to catch gravitational waves that had been theoretically predicted a century ago, and now we will see the emergence of a new branch of astronomy. The Tartu Old Observatory and later the Tartu Observatory have participated in that voyage and the many discoveries it has brought for the past 200 years. Some of the most notable events have been commemorated at this exhibition.
It is certain that we know more of the universe than we did 400 years ago but a large part of the cosmos continues to hide its true nature from us. This means that our cosmic journey of discovery is far from over.
The exhibition is supported by Eesti Kultuurkapital.