Lecture by Prof. Ed van den Heuvel at Maastricht University

On January 17th, 2018, Prof. dr. Ed van den Heuvel will be talking about the Wonderful Unity of the Universe. This takes place at the University of Maastricht (NL) 20h00.

Space Weather Flow Chart

I made a Space Weather Flow Chart which provides an oversight on solar phenomenon, solar activity, effect and consequence.

Versie 2 van Onze Zon : De meest nabije ster

De afgelopen maanden noteerde ik alles wat maar enigzins te maken had met de zon. Dit met de bedoeling om mijn eerste versie van mijn paper "Onze Zon : De meest nabije ster" aan te passen en af te stemmen op deze nieuwe informatie. Mijn Kerstverlof was er dus aan voor de moeite maar heeft wel geleid tot een nieuwe tweede versie van mijn paper.
Je kunt het werk hier downloaden en ik wens iedereen veel leesplezier. 

ISS Crossing Disk of the Sun

Tomorrow, Wednesday December 27, around 13h57 (12h57 UT) ISS will be crossing the Disk of the Sun between Antwerp and Liege. This is only visible using a small telescoop with Solar blocking Filters.

Orion Nebula M42

Using a different way of editing my astropictures within CS4 gives some nice results. As an example I used a picture of M42 (Orion Nebula). The technic used results in a complete shift of the histogram and taking out some noise.

Congratulations

Celebrating 5 years of blogging.

Astronomical Highlights 2017

My Astronomical Highlights of 2017 is, of course, the Great American Eclipse. Beside this wonderful and beautiful moment also other moments are worthwhile to share :

Solar Eclips in Rexburg Idaho Aug 21, 2017

The Milky Way or a Meteor as seen in National Park Arches (Utah)

The Sun this year with a perfect 360° Halo and with Sunspots (even when the Sun is getting into a minimum period) :

The Planets this Year with Saturnus and Jupiter :

Deepsky  Objects M42 en M51 :

And My Solargraph using a 72cl can :

Ms Hisako Koyama - Observing Sunspot for more then 40 Years

Hisako Koyama +40Years Observation of Sunspots

Via the website of the University of Colorado Boulder I found an article on "Hidden Figure" Hisako Koyama. She is a Japanese Solar Observer and observing +40 years of sunspot and making +10000 drawings. 

To better understand the solar cycle, an international group of scientists reconstructed the number of sunspots seen each year since scientists first observed them by telescope in 1610. A researchers team searched through original sunspot observations for the past 400 years and discovered Koyama’s work in Japan. They combined her collection of drawings with those of Galileo Galilei, Pierre Gassendi, Johann Caspar Staudacher, Heinrich Schwabe and Rudolf Wolf to establish a continuous sunspot count for the past four centuries. 

Those five names are the giants of sunspot records. Koyama’s more than 40 years of drawings proved invaluable to the scientists because few solar observations have been collected by the same person, using the same telescope and using the same observation method for such a long time. 

Her drawings are digitized and available via the Japanese National Museum of Nature and Science.

 

Interesting to note is that she is one of few people who ever witnessed a white-light flare with the naked eye. She recorded this on November 15, 1960.

If you want to search into the archieves for digitized sunspot drawings, use this link.

Winter Solstice

The Astronomical Winter will start Today at 17h28 local time (UT 16h28) and it is the Day with the least Sunlight.

Solargraphs Results

Magnificent Solargraph from the period July-Dec 2017 using a 72cl can with Ilford MGRC Multigrade RC Cooltone photopaper.

Solargraph made with 72cl can

Six months ago, I installed two pinhole camera's with the intention to track the sun's orbit at the sky. This was my sixt consecutive year doing these experiments. This is what I learned this year :

1)  One of my pinhole camera's had a rather large pinhole. This can result in an overexposure, so keep the pinhole as small as possible;

2)  I used a 72cl can and the results is much better when comparing with a 50cl can;

Second Solargraph : 50cl can with rather big pinhole resulting in an overexposed Solargraph

  

Pinhole Camera Ready

This year I made 5 pinhole camera's to collect Solarbeams with Solargraphs as an end result ... hopefully.

Star Wars VIII

Watching yesterday the new Star Wars "The Last Jedi" and Again it is a fantastic Episode of Star Wars. Great graphics and beautifull landscapes makes this movie one you should have seen.

Workshop Solargraphy

Presentatie van Workshop Solargraphy gegeven tijdens Helios vergadering op 10 december 2017. Klik hier voor de PDF versie van de presentatie.

Solargraph met 50Cl blik.

Morning Sky with Jupiter and Mars

Clear morning Sky with Jupiter and Mars at the Eastern Horizon. Picture taken using IPhone 6 with LR in kasteelhoeve De Kerckhem

ISS Crossing the Sun's Disk on December 9th

Great opportunitiy to see the International Space Station ISS crossing the Sun's Disk on December 9th around 15h 05m.

NEVER LOOK DIRECTLY AT THE SUN. Do NOT look at the sun without protection, use only protective safe filters - No sunglasses!

The centerline starting at Brussels through Eindhoven including Leuven, Aarschot, Geel, Mol, ..

Solargraph

All you need to make your own pinhole camera from a ordinary (beer)can creating solargraphs.

Nitrogen Dioxide above Western Europe

The Sentinel 5P provided images of the distribution of Nitrogen Dioxide above Western Europe. Nitrogen Dioxide is mainly generated by industrial fossil fuel combustion and air traffic.

Picture from November 22, 2017 - Credit KNMI/ESA - Copernicus

Feedback from Janneke Schenk

Friendly feedback from Janneke Schenk, auteur of the book "Over de Regenboog".

Over de Regenboog - Janneke Schenk

I found a compact and interesting book on rainbows, corona's, and other phenomena linked to our Sun. The book is written by Janneke Schenk and beside many and very beautiful pictures the book explains those phenomena's in an easy but still scientifically way.

Rainbows are impressive natural phenomena. But where do the colors of a rainbow come from? Why does it have the shape of a bow? Does a rainbow always look the same, and how big is a rainbow? Are all rainbow colors in the sky rainbows?

Janneke Schenk looked for answers to these questions and encountered other light and color phenomena on our way, such as the corona, glory, sacred and halos. She describes the physical explanation of these phenomena and makes them understandable for everyone with the aid of illustrations and photographs.

Through knowledge of the processes and circumstances you develop a feeling for where and when special light phenomena can be found in the sky and you will notice them more and more often!

See my other books in my library.

Supermoon Sunday December 3

Sundaynight, December 3th it will be full Moon. And as the Moon is much closer to the Earth then normal average the Moon will be 7% wider and 13% more brighter. This is called Supermoon. Have a look at the sky tomorrow evening and verify yourself :)

The full Moon on March 12th, 2017 was 1,2% smaller then normal average.

Weather Summary November

Average temperature in November is about 2°C below long term avarage. In total 8 air frost days are counted. Rainfall is normal with 60 l/m2 and comparable with previous 3 years.

Part of Winter Hexagon

The area of Gemini and Auriga are part of the winter hexagon and have some interesting open clusters like M35, M36, M37, M38 and M44. The picture is not that good but it gives a nice overview.

Photokina 2018 : Block Your Agenda

Photokina is the world’s leading trade fair for the photo, video and imaging sectors. More extensive than any other event in the world. And you can join next year 2018 from September 26-29 in Cologne (Koln-Germany). 

The year after, in 2019, the trade fair will be again organised. This time in May which will be start of an annual cycle.

Perfect Observation Sites in the BeNeLux

The Deep Sky Group from the VVS provides the best observation locations in the BeNeLux. - see this link.

ATT Essen : Block Your Agenda

ATT Essen (European biggest Astronmy fair) will take place on May 5th, 2018 in Essen - Germany. 

Electromagnetic Spectrum of the Sun : Microwaves Part 1

Can we observe the entire electromagnetic spectrum of the Sun on Earth?  The answer is no. Once the radiation penetrates through Earths atmosphere some are reflected, absorbed or scattered.  This is shown in below graph provide by NASA.

The common electromagnetic radiation from the Sun observed on Earth are visible light, microwaves and radio waves.  Microwaves are defined as waves with wavelenghts between 1m and 1mm and thus a frequency between 300MHz en 300GHz. This is calculated via

wavelength (m) = phase speed (m/s) / frequency (Hz)  (Phase speed in space equals speed of light)


In a next article I will explain the correlation between Sunspot data and microwaves emitted from the Sun.

Buying Guide Best Cameras : Nikon D7500

DPReview provided their 2017 list of  Best Cameras by Use case and by Price Case.

My Nikon D7500 is picked

- as Best Camera in the category "by Price Case under $1500".
- as Third Best Camera in the category "for parents"
- as Fifth Best Camera in the catergory "for Sports and Actions"

This is the feedback from DPReview :

Nikon D7500 20.9MP APS-C CMOS Sensor | 51-point AF system | 3.2" tilting touch LCD

What we like:
Excellent image quality
Deep buffer and fast burst rate
Impressive AF subject tracking through the viewfinder
Small and light for a DSLR in this class

What we don't like:
Crop factor limits lens choices when capturing 4K video
Snapbridge Wi-Fi system needs improvement
Mediocre video autofocus

The Nikon D7500 is a capable and refined DSLR that produces excellent quality photos from its 20.9 megapixel CMOS sensor and also offers an impressive buffer and reliable autofocus system.

For a twin dial DSLR, it is relatively compact, but is definitely larger than most mirrorless competitors. It has a deeper grip than its predecessor, as well as improved weather-sealing. The flip-out touchscreen is responsive and can be used for focusing, menu navigation or image playback. The optical viewfinder is well-sized and has an eye sensor that turns off the LCD when you're using it.

Autofocus performance from the 51-point AF system is also quite good. The camera subject tracks with impressive accuracy thanks to its 180k-pixel RGB metering sensor. An 8 fps burst rate, coupled with a buffer depth of 50 Raw or 100+ JPEGs, means the D7500 is well-prepared for sports or action.
The camera also tracks with impressive accuracy thanks to its 180k-pixel RGB metering sensor.

Image quality from the D7500 is excellent. JPEG color tends to be pleasing, and noise reduction at high ISOs tends to be well balanced. Raw image quality is exceptional, in terms of both dynamic range and low light noise.

The D7500 can shoot 4K/UHD video but with a 1.5x crop factor (on top of the existing 1.5x APS-C crop factor), which can be pretty limiting. The quality of the 4K footage is competitive, though. The camera is also capable of Full HD video capture at up to 60 fps. Auto ISO can be used during capture and the camera has a built-in mic jack (no headphone). Autofocus during video capture is not very useful, since it's noisy, jumpy and occasionally hunts for focus.

If you're in the market for a DSLR under $1500, the D7500 is strong choice. As one of Nikon's enthusiast-grade APS-C cameras, it offers plenty of controls, customization and impressive performance that should satisfy the most demanding of stills shooters. While it can shoot 4K video, there are plenty of cameras that do so with better autofocus and no crop factor. At the end of the day, for a stills-focused photographer the D7500 an excellent camera - and one that can make use of a vast range of Nikon and third-party lenses going back decades.

Less then a month to go

On december 21 it's again time to set up for your next solargraph. So you have 4 weeks to prepare making your own pinhole camera. DIY Instruction are available via my blog link here.

I will be preparing my next ones as well ... :) and it's not about the beer... it's about the 50cl cans.

On december 21, I will remove my installed pinhole camera's which are out since June 21. It will be my first results of the period June-December. All my previous Solargraph are made in the period Dec-June.  I'm curious about the result and what would be the difference between the periods.

Pinhole Camera Installed Since June - Size of the can 71Cl

Pinhole Camere installad since June - Size 50Cl