Report about the "Sternstunde" on November 17th, 2023

A "Sternstunde" is described, which is regularly offered by kosmos-os.de as so-called sidewalk astronomy. Although Osnabrück is heavily lightpolluted interesting observations of the sky were made.

We would like to introduce: The planets Jupiter and Saturn. People noticed them a long time ago because they “walk around” among the stars. Today we know that these planets orbit the sun like our Earth. Because they are still quite close to us by cosmic standards, we can see from Earth how they move in front of the much more distant and therefore seemingly stationary stars. This is even possible from Osnabrück, despite all the light in the city. However, the sky must also be reasonably clear and the sun must have set.

On Friday evening, November 17th, 2023, Jupiter and Saturn were our attractions in the sky above Willy-Brandt-Platz in Osnabrück. By 6:30 p.m. we had set up our two telescopes; a refracting telescope of the apochromat type and a so-called Dobsonian reflecting telescope. Both gave our visitors an impressive magnified view of the two giant planets.

Together with Jupiter waren alle vier sog. galileischen Monde Callisto, Europa, Io und Ganymed zu sehen, letzterer ganz dicht an der großen Planetenscheibe.  Sogar die Wolkenbänder des Riesenplaneten waren deutlich zu sehen. Ein majestätischer Anblick! Man muss sich verdeutlichen, dass wir aus immerhin 600 Millionen Kilometern Entfernung auf Jupiter schauten; und das aus dem hellen Osnabrück!

Saturn is even further away from us at 1,400 million kilometers! Nevertheless, it showed all its splendor in our telescopes. Its ring system gives it its distinctive appearance. The resolution of our telescopes was so good that the planet's shadow could be seen on its rings. Also its largest moon Titan, with a diameter about 1.5 times larger than that of our Erdmond, couldn't be overlooked.

Of course we were also able to show constellations: Swan, Lyre, Eagle, but also Pegasus, Andromeda and a few others, whose main stars were bright enough to penetrate Osnabrück's dome of light.

Every now and then clouds came by, pulling the curtain over the stars. We were able to use these involuntary breaks for more detailed explanations and some technical talk.

Almost at the end of our observation evening, we didn't miss the opportunity to take a look at the star "Epsilon Lyrin the constellation Lyra, whose light traveled to us for 160 years. So it is much, much further away than Jupiter or Saturn. From there the light makes it to us in less than an hour. To the naked eye the star appears as a simple point of light, but in a telescope we saw two stars. In fact, there are 4 stars that orbit each other, which is why it is also called a “Double-Double”.