The image depicts Comet 12P/Pons-Brooks and the Andromeda Galaxy, captured from a serene meadow near Revúca, Slovakia. Positioned low on the northwestern horizon during the capture, both celestial objects adorned the dark sky with their celestial beauty. As the comet slowly traverses through the constellation Andromeda, it shares the cosmic stage with the prominent spiral galaxy, also known as M31. While the comet maintained a distance of 1.7 AU (about 250 million kilometers) from Earth at the moment of the snapshot, the galaxy is on the order of a hundred billion times farther away. In early March, the comet began an exciting journey, passing close to the galaxy in the sky. The closest encounter between the comet and the galaxy occurred on March 9, at a mere 9° southwest.

In the weeks ahead, the comet will gradually move towards the constellation Aries, becoming observable from 27th of March until April 19th. Following this period, it will fade from our view as twilight brightens the western horizon in the constellation Taurus. Presently at magnitude 6, it is expected to increase in brightness to magnitude 4.5 in the upcoming weeks. Even under dark skies distant from urban areas, experienced observers may detect it as a faint spot with the naked eye. However, locating it now requires the use of a map and small binoculars. For further details regarding the comet's visibility, please refer to a recent press release.

The photo shoot was a culmination of both fortunate circumstances and diligent preparation. “Despite the promising forecast, I had to drive over 300 km to only realize that on the evening of March 5, 2024, my chances of capturing images of Comet 12P/Pons-Brooks were slim. Upon arrival in Telgárt, Slovakia, the sky was disappointingly veiled by thick clouds. I knew I had about 2 hours to get some shots of the comet. I quickly decided to move south, towards the town of Revúca. There was really thick fog on the road the whole way. When I finally reached Revúca, the sky had cleared. However, my unfamiliarity with the area posed a challenge in finding an optimal vantage point to capture the comet. Finally, when I was about to give up and turn back, a field path appeared ahead of me on the right. So I drove up on it, opened the door and was greeted by a a perfect view. I didn't waste any more time, stopped the montage and started shooting blindly. Only in the pictures did I find out that the composition is actually very nice, with a distant tree and fog lit by passing cars,” as Horálek remembers a blessing in disguise that led to the creation of the image. This is already the 15th NASA image of the Institute of Physics in Opava and the 19th NASA image that was taken in Slovakia.

The comet appears significantly more prominent in photographs compared to observations with the naked eye, attributable to various factors. Firstly, photographers typically capture the comet from locations far from urban areas with light pollution, resulting in a more contrasted sky where the comet and its tail stand out vividly in images. Additionally, cameras possess heightened sensitivity during nighttime, surpassing the capabilities of the human eye in detecting both color and the brightness of faint objects. Therefore, the comet also stands out in photographs with its relatively long ion tail, but it is very difficult to observe with the naked eye. Numerous images of the comet are circulating on the Internet, but it's important for people to understand that many of these were captured using telephoto lenses, exaggerating the brightness and size of the comet in the pictures. "It's crucial to consider how the images shared online were captured. It is reported that a full-frame camera, paired with a 50mm lens, provides a perspective and angular size of objects closest to human eye perception. My own picture was taken with a 70mm lens, resulting in a scene zoomed in approximately 1.4 times compared to human eye perception," notes Horálek in a recent Facebook post.

The NASA Astronomy Picture of the Day (APOD) stands as a prestigious accolade, awarded to the most captivating astronomical photograph of each day. Carefully selected and supplemented with an enlightening descriptions by editors Professor Jerry Bonnell from the University of Maryland and Professor Robert Nemiroff from Michigan Technological University, both esteemed collaborators with NASA, APOD serves as a beacon for celestial enthusiasts. With its motto, "Discover the Universe," APOD has garnered global recognition since its inception in 1995, emerging as one of the foremost platforms of its kind worldwide. The accompanying narratives are translated into 23 languages, including Czech, under the thorough care of Josef Chlachula since 1999. APOD captivates the minds of hundreds of millions of daily visitors across various social media platforms. For further details, visit the website of the Czech Astronomical Society.

Website links of the APOD picture:

Contact details and additional information:

Mgr. Petr Horálek

RNDr. Tomáš Gráf, Ph.D.

prof. RNDr. Zdeněk Stuchlík, CSc.