Category Archives: Astronomy

Astronaut meets Cartoonist

The Guardian: Chris Hadfield meets Randall Munroe: ‘Are we alone in the universe?’
“Chris Hadfield, the Canadian astronaut and internet sensation
Randall Munroe, the US cartoonist and former Nasa physicist

“The Canadian astronaut Chris Hadfield spent five months in 2012 and 2013 twirling around the Earth in command of the International Space Station. Hadfield guesses he made several thousand orbits of the planet during that time […]
The American artist Randall Munroe knows something, too, about capturing an audience in the age of the fast and fickle online share. Munroe’s webcomics, produced under the banner of xkcd and promising “romance, sarcasm, math and language“ , have for years been a part of the social media fabric.”

Great interview. I recently read An Astronaut’s Guide to Life on Earth and enjoyed it immensely. Also, Munroe’s explanation of orbital speed with the Proclaimer’s hit I’m gonna be (500 Miles) is great!

Link via MetaFilter:“When you looked down at Earth, did you always know where you were?”

Sein Traum, Astronaut zu werden, wurde wahr

Spiegel online: 166 Tage im Weltall: Mit Alexander Gerst auf der ISS.
In der 43 Minuten lange Dokumentation berichtet Gerst über seine Mission, angefangen vom der Vorbereitung über den Start und die Zeit an Bord der ISS, über seinen Space Walk und schließlich den Rückflug und die Landung auf der Erde.

Alexander Gerst war an der Blue Dot Mission auf der ISS beteiligt, die vom 28.05.2014 bis zum 10.11.2014 dauerte. Er landete also vor einem Jahr und 3 Tagen wieder auf der Erde. Von unterwegs veröffentlichte er hunderte von beeindruckenden Fotos auf Flickr.

In English: Alexander Gerst was the third German astronaut aboard the ISS and participated in Expedition 40/41

ESA: Gerst-Biographie der ESA, Gerst’s personal ESA page and his Blue Dot Blog, and the Blue Dot Mission

He posted hundreds of amazing photos on his Flickr account during his mission.

ESA Blue Dot mission / Alexander Gerst playlist on YouTube

Sonnenfinsternis

After missing the previous total solar eclipse that was visible in Germany in 1999 due to excessive cloudage in Bonn I was doubly lucky today: There wasn’t a single cloud in the sky, and my timetable at school allowed me to watch the entire eclipse from start (9:29am) to finish (11:49am).

I had a pinhole camera, eclipse glasses and a sun projector at my disposal. Many students also had brought eclipse glasses and/or pinhole cameras, and the beginning of the eclipse happened just before the end of recess, so everyone was keen on taking a first look.

The sun projector proved to be a huge hit as it provided the largest picture of the sun with a diameter of about 5cm; here’s a (bad) photo I took of the projected image around 11:24am, only half an hour before the end of the eclipse:

While discussing the upcoming eclipse with my tenth grade yesterday we noticed the pattern of circles that the sun was making on the classroom floor. I realized that the holes in the blinds act like pinhole cameras and predicted that the circles would turn into crescents during the eclipse, but I think most of the students did not quite believe me until they saw it today – there were rows upon rows of tiny eclipses all over the floor and walls:

One student showed me this photo she had taken and wanted to know why the sun seemed to be whole while the eclipse was visible above and to the right:

It turns out that the sun was still so bright that that its shape was not accurate*, but the lens flare showed the eclipse – how cool is that?

*I know there’s a proper term for this that refers to the fact that when too much energy reaches one pixel it overflows to the neighboring pixels, thus altering the form of the lightsource you’re photographing, but I can’t remember it right now.

Zum Abschluss noch ein paar Links auf deutsch für die geneigten Leser aus der Nachbarschaft:
Sonnenfinsternis am 11. August 1999 und Sonnenfinsternis vom 20.03.2015 (heute), Lens Flare bzw. Linsenreflexion

Besondere Erwähnung verdienen die Sonnentaler – für die gibt es keinen englischen Begriff, so weit ich weiß. Gemeint sind die Lichtflecken, die ein dichtes Blätterdach oder auch kleine Öffnungen in Rollläden/Jalousien verursachen und die heute während der Finsternis als kleine Sonnensicheln zu sehen waren. Die Entstehung beruht auf dem gleichen Prinzip wie die Bildentstehung bei einer Lochkamera.