Astronomical clock in Hewelius city

Astronomical clock in Hewelius city

Did the history made a circle? From the earliest times, astronomical phenomena gave the rhythm to our planet. In antient times We started to count the time on the basis of the sun’s position in the sky. Now, We regulate our watches using pulsar signals. The most accurate timepiece in the world that counts the seconds is situated on St. Catherine church tower in Gdansk.

Astronomers believe, that the pulsar is the most reliable pattern of time that was given to us by nature. If yes, why not constructing a clock using that pattern? Several science centres around the world are working on using pulsar to synchronise atom clocks. Those are still in progress in laboratories. Without the the proper program to the pulsar clock what would be synchronised with the real time send by pulsar signals.

The international lighthouses

When the star burns all its power in hydrogen supplies, it collapses and explodes with a great power ( so called supernova), throwing around its pieces into the outer space. The core, that is left after the explosion is relatively small ( thinking about the space scale) – the best investigated pulsar so far situated in a double system EXO 0748-677, has the diameter not more than 30 km. Its weight is around three times more than the weight of our sun.

At the moment of neutron star shrinking its spinning frequency is getting bigger. The core of the closest to us star makes the full spin in around more or less 20 days. Pulsars spin much quicker – they spin around 600 times in a second. While doing that, they radiate from its both poles enormous, pulsating visible spectrum or X-ray. Scientist call this kind of star a “lighthouse” model.

Pulsar model. Source: www.nasa.gov

Every time the pulsar spin, it sends regular radio waves which can be caught by  the radio telescope. Such signal is a very accurate in time – even more that atom clocks.

Until today astronomers discovered more than 1900 pulsars. One of the most famous pulsar is the one in the centre of the Crab Nebula. Its explosion was so enormous that for the first two years it could be seen form the Earth.

 

From the idea to implementation

At the begging of XXI there was an idea of constructing a clock that would be pulsar based. In 2009 that idea was completed – by the investor Museum of Gdansk, which cultivates the figure of Gdansk astronomer Jan Hewelius ( more about the astronomical achievements of this famous Gdansk citizen You will find here), So constructing the first in the world pulsar clock was one of the best idea to commemorate this famous scientist in the year  of his 400 birth anniversary.  The scientist group was organised with its leader, the founder of the pulsar clock idea, Grzegorz Szychliński form Gdansk Museum, Mirosław  Owczynnik and Dariusz Samek, engineers of electronics from Gdansk EKO Electronics company and Eugenius Pazderski, one of the best specialistsin Poland in radio astronomical  devices from Astronomical Centre from Nicolaus Copernicus University in Torun.

The aim was to build a device, called Pulsar Time Scale, the most stable time scale so far. Built in Gdansk pulsar clock should be a platform, which aim is to prove the point of this idea and leading this technology to the perfection. The organizers were impressed with the accuracy  and stability of such clock in long time frames, versatility of such pattern (If supposedly all clocks would stop working, from the pulsar scale would  enable to get the proper time back) and on the other hand they were impressed by the metaphysics of such device, which counting the time relates to the signals send from the galaxy.

The  mechanism of this special device will be based on the impulse send by the most alluring space thing – pulsar, so neutron stars, created after the supernova explosions, which  radiate in a very regular way. Pointing out the space location of the clock towards the pulsars, by the use of special  analysis to the difference of the signal ways – sophisticated programs and algorithm will be used here. In this process mathematical models of the Earth movement towards the barycentric of solar system and the knowledge of the sun’s movement is the galaxy are used. By observation of bigger number of pulsars, using special programs it is possible to update the model parameters. This sophisticated mechanism was placed  in St. Catherine church in Gdansk, in the centre of the Old Town, 20 meters from Jan Hewelius tomb , at the Earth point 54°21'15"N, 18°39'6"E.

Why in Gdansk? There are several reasons. Jan Hewelius – famous Gdansk astronomer, the author of the pendulum clock prototype, was form Gdansk. What is more, in this city the pulsar signal is very strong and the presentation of the device was organised along with 400 anniversary of the scientist’s birthday.

More about Gdansk pulsar clock and other scientific curiosities You will find here - Museum of Gdansk Science (Muzeum Nauki Gdańskiej)