Beautiful and Active Sunspot AR2661

Sunspot AR2661 is growing and with an open sky this morning, I was able to take some pictures in visual aswell in H-alfa. Using my TAL200K f/10 with Astrosolar filter ND5 results in a shutter speed of 1/500s applying ISO100. This resulted in a very sharp picture with a lot of contract and details. Editing was done using CS4.

Near Sunspot AR2661 and seen at the "edge" of the sun, some big prominences could be observed using my PST40. The best result was realized using ISO800 and a shutter speed of1/25s. The picture was taken afocal on a zoom lens 8-24mm on 24mm and finished using CS4.

Parker Solar Probe : Touching the Sun

In July 2018, NASA will launch their first mission ever to fly directly into the sun's atmosphere. It will orbit within only 6 million km from the sun's "surface".  To compare : the sun's radius is about 695990 km and the distance earth-sun is 150 000 000 km.
The objective of this mission "Touching the Sun" is to understand better what's happening in the sun's atmosphere and gatter data to predict space weather more accurate.
The mission is named after Eugene Parker, who in 1958 announced that the sun constantly sends out matter and magnetism affecting the entire solar system. Today we know this is as the solar wind forming the Heliosphere.

Ligo detects gravitational waves for the third time.

For the third time, LIGO spots gravitational waves? This time the merging black holes are as far as 4 billion ly (farrest so far) from earth and a combined 49 sunmasse s - see article.

Update geschiedenis van astronomievereeniging Helios

De geschiedenis van astronomievereeniging Helios te Averbode werd geactualiseerd. Zie hiervoor link naar de blogpagina.

Start of NLC season

June and July are typically the start of NLC or Noctilucent Clouds. Those highest clouds we know are showing up around 80km above Earth's surface. They are very cold and exist of very small ice crystals. When sunlight hit those crystals they will show up as a blue glow. They appear during the summer months and the best way to observe is about 2à3h after sunset or 2à3h before sunrise.

The picture below I took last last year mid July, 1h before sunrise.

How to calculate exposure time during suneclips

When making pictures of the sun and during a totality it's important to have the right settings. You can experiment yourself upfront with the sun high in the sky and using your solarfilter. Try out shutter speeds from 1/8000s -1s for different ISO numbers and f/stop numbers and see what's the best result. As long as the sun is visible this setting can be used. During totality settings need to be adjusted and without filter.

For more information see this calculator or see below chart for settings during totality and what detail (chromosphere, corona,..) you want to photograph

Weather Summary May 2017

As a summary May 2017 was a warm and dry month.
Average temperatures are up to 2°C higher then last three years. In comparison with last 4 years, May 2017 was a very dry month with 23 dry days and only 45 liter/m2.