Solar Cycle 25 Begins
17.09.2020

The general trend of monthly sunspot data now confirms that the minimum of the approximately 11 year cycle of solar activity occurred in December 2019, marking the start of Solar Cycle 25. That quiet Sun, at minimum activity, appears on the right of this split hemispherical view.

APOD: 2024 January 8 Б The Phases of Venus
8.01.2024

Venus goes through phases. Just like our Moon, Venus can appear as a full circular disk, a thin crescent, or anything in between. Venus, frequently the brightest object in the post-sunset or pre-sunrise sky, appears so small, however, that it usually requires binoculars or a small telescope to clearly see its current phase.

APOD: 2025 January 7 Б A New Years Aurora and SAR Arc
7.01.2025

It was a new year, and the sky was doubly red. The new year meant that the Earth had returned to its usual place in its orbit on January 1, a place a few days before its closest approach to the Sun.

Spherical Planetary Nebula Abell 39
23.01.2001

One of the largest spheres in our Galaxy is giving valuable clues about the chemical composition of stars by its very shape. Planetary nebula Abell 39, now six light-years across, was once a sun-like star's outer atmosphere expelled thousands of years ago.

Pyramid Ice Crystal Halos Over Finland
18.06.2008

What if the atmosphere above you became one gigantic lens? This actually happens when a nearly transparent sheet of pyramid shaped ice crystals falls from the sky in a common orientation. These ice-crystals...

M97: The Owl Nebula
15.05.2009

The Owl Nebula is perched in the sky about 2,600 light-years away toward the bottom of the Big Dipper's bowl. Also cataloged as M97, the 97th object in Messier's well-known list, its round shape along with the placement of two large, dark "eyes" do suggest the face of a staring owl.

Interstellar Interloper 2I Borisov
18.10.2019

After the 2017 detecton of 1I/'Oumuamua, comet 2I/Borisov has become the second recognized interstellar interloper. Like 'Oumuamua, Borisov's measured hyperbolic trajectory and speed as it falls toward the Sun confirm that its origin is from beyond our Solar System.

APOD: 2024 June 12 Б Aurora over Karkonosze Mountains
12.06.2024

It was the first time ever. At least, the first time this photographer had ever seen aurora from his home mountains. And what a spectacular aurora it was. The Karkonosze Mountains in Poland are usually too far south to see any auroras.

Comet Lovejoy through Morby Castle Ruins
4.12.2013

This new comet is quite photogenic. Comet Lovejoy, discovered only three months ago, was imaged through ruins of ancient MЖrby Castle in Sweden last week sporting a green-glowing coma and tails trailing several degrees.

Planet Earth at Blue Hour
11.10.2019

Nature photographers and other fans of planet Earth always look forward to the blue hour. That's the transition in twilight, just before sunrise or after sunset, when the Sun is below the horizon but land and sky are still suffused with beautiful bluish hues of light.