The Sun

 

Sunny days and the sun shows several sunspots and prominences. The images were taken with Ha and CaK filters, different wavelengths.

 

A CaK filter (Calcium K-line filter) is a specialized solar filter for telescopes that isolates light at a specific wavelength of 393.3 nm in the deep violet/near ultraviolet (UV) spectrum. The filter is used in astronomy to observe and photograph the sun, as it makes the lower chromosphere and the border region with the photosphere visible.

 

H-alpha solar filterH-alpha solar filterA H-alpha (Hydrogen-alpha) solar filter is a specialized and advanced optical system that isolates an extremely narrow light wavelength of 656.28 nanometers (nm), which makes it possible to safely observe the sun's chromosphere. Unlike regular white light solar filters, an H-alpha solar filter shows dramatic details such as prominences (gas clouds ejected from the edge), filaments, sunspots and solar flares.

Milky Way

Imagine being able to see our own galaxy, the Milky Way, with the naked eye. But you have to get away from all light pollution, away from cities and even local lights. The moon must not interfere either. Wait to get night vision (10-40 min), no lamp on or mobile phone on - then you will see the Milky Way as a band across the sky. These pictures were taken in Gekland and there you can also see the center of the Milky Way, which is seen as a large cloud in the night sky. This part of the Milky Way cannot be seen from Sweden.

The center of our galaxy is located 26,000 light-years away from Earth in the Sagittarius constellation. It features a supermassive black hole called Sagittarius A*, which is about 4 million times heavier than our Sun. Thick cosmic dust hides this busy, star-packed region from normal view.

Astronomers estimate that the Milky Way contains between 100 and 400 billion stars. Because we are inside the galaxy and obscured by thick clouds of gas and dust, we can only roughly calculate the total by measuring the galaxy's mass and observing the movement of its stars

Bright NLC´s

 

Noctilucent clouds are the highest clouds in Earth's atmosphere, forming in the mesosphere about 76 to 85 kilometers (50 miles) above the surface.

Meaning "night-shining" in Latin, they appear as electric-blue, silvery, or glowing wisps during summer deep twilight when they are illuminated by the sun from below the horizon.

Noctilucent clouds (NLCs), also called polar mesospheric clouds (PMCs) when viewed from space, are a tenuous atmospheric phenomenon. Unlike typical weather clouds that form less than 12 miles above Earth, NLCs occur at the very edge of space.How

For noctilucent clouds to form, three precise ingredients are required:

Extremely Low Temperatures: Temperatures in the mesosphere must drop below -120°C to -140°C.Water

Trace amounts of water vapor must be present.

Tiny dust particles are needed, primarily from micrometeors burning up in the atmosphere.

Water vapor freezes onto the meteoric dust to form microscopic ice crystals, which reflect sunlight. Their striking blue color is a result of the ice crystals scattering sunlight in the upper atmosphere.

Noctilucent clouds are a seasonal and latitudinal phenomenon. They occur only during the summer months when the upper atmosphere above the polar regions experiences its coldest temperatures.

Northern Hemisphere: Best viewed between mid-May and mid-August, primarily at mid-to-high latitudes (roughly 45° to 80° North, including northern Europe, Canada, and the northern United States).

Southern Hemisphere: Best viewed between mid-November and mid-February

Photos taken in Vallentuna Sweden 16-17/7 2026.