Sunspot AR2887 in Ca-K

Sunspot AR2887 was observed in Ca-K with setting: ASI224MC, TAL200K f/8.5, solarfilm ND3.8 and. 30s. Pictures stacked using AutoStakkert and final editing with CS4/

Halo with Parry Arc and Parhelic Circle

This afternoon the Sun could be observed with a 22° halo but also with some other arcs and circles.

Halo with Sun dogs

Halo with with on both sides bright Sun dogs.

Body Mass Index and Bruges Meridian Line

Sometimes a title needs to grab your attention…

Over the past few months I visited Bruges several times which allowed me to explore Bruges in a different way instead of a typical tourist tour. Inspired by Patrick Wouters' lectures on the meridian lines, I did some research before my visit. According to various information, there are Belgian meridian lines in Brussels, Antwerp, Ghent, Dendermonde, Aalst, Lier, Mechelen and one in Bruges. In Bruges we find the meridian line on the market place, Grote Markt. The meridian line itself is visualized by a row of copper plates in the ground over a length of 65 meters. According to the literature, this is not the original line applied by Adolphe Quetelet. It is not even clear whether there has ever been a “line”. On the “true noon” a replica copper-colored sphere casts its shadow on this meridian line. This 50 cm large sphere stands on top of the mansion "Huis Bouchoute" (1480) which today houses Brasserie "Meridian 3". 

Some more history. It was the astronomer Adolphe Quetelet (1796-1874, director of the Royal Observatory of Belgium) who was responsible for the construction of the Bruges meridian line at the request of the government (RD 22/02/1836). The Bruges meridian line would be completed on July 28, 1839 (Ref 1). The meridian line would be part of no fewer than 41 planned meridian lines at various places in the country, of which Quetelet eventually built 10. The intention was to harmonize time in different places in our country. This harmonization became important due to the expansion of the Belgian rail network (from 1835). Because cities had their own time, the safety of train traffic could not be guaranteed. At that time, trains still ran on one track, so you don't want unplanned oncoming traffic 😊. By the way, did you know that Adolphe Quetelet was the basis of the BMI (Quetelet Index (Ref 2)), yes, the Body Mass Index!

Reference 1

Reference 2

Jupiter

Clear sky but low seeing which in very poor results.

Setting : ASI 224MC with TAL200K, Barlow x2 and ADC. In total 3000 frames are stacked using AutoStakkert! and final editing using CS4 and DeNoise AI.

My picture on National TV (again)

My picture, which I took this morning, of the port of Oostende was broadcasted on the National TV. During "Het Weer", the daily weather forecast from channel 1, my picture was presented by Frank Deboosere.

Black Holes and Gravitanional microlensing by Prof Lukasz Wyrzykowski

Selfie with Prof. Lukasz Wyrzykowski

Last saturday, October 2nd, Prof. Lukasz Wyrzykowski from the Astronomical Observatory of the University of Warsaw, gave a lecture on "How to find black holes with gravitational microlensing". The lecture was given as part of the JVS/VVS astronomical weekend at Oostend (Belgium).