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The Pleiades, a winter classic

Dear friends of The Lonely Photon,

Here’s another recent work I’m enormously proud of: the Pleiades!

A little background.

The Pleiades is an extremely popular target among astrophotographers, one of those that can seriously push you deep into the hobby. So, naturally, when I started my journey into astrophotography two years ago, I had very high hopes for this target.

Pretty soon, however, my hopes clashed with reality. Imaging the star cluster is easy enough, as it is very bright and can be easily seen with the naked eye, even from light polluted cities; what’s way more challenging is pulling out all the surrounding dust, which can be quite elusive, particularly from the Bortle 8 sky I live (and photograph) under.

To get that faint nebulosity and dust you need several hours of data integration, good weather and good seeing on moonless nights, and of course dark skies; something quite rare where I live. Against any odds, however, February 2023 presented me with an opportunity: two clear nights just around the new Moon. I couldn’t believe it.

Now, I had my moonless nights to get the necessary integration, but there was nothing I could do about the dark skies. To mitigate that I used a light pollution filter, the Optolong L-Pro, but this had previously given me mixed results, so I wasn’t too optimistic. It was only when I went to process the data that I found out: I had done it, I finally managed to pull out the dust and nebulosity that surrounds the Pleiades. Happiness does exist!

The Pleiades

In Greek mythology, the Pleiades were the seven daughters of the Titan god Atlas who rebelled against Zeus and was thus sentenced to hold up the heavens on his shoulders. Moved by compassion, however, Zeus allowed the seven daughters a place in the sky so they could stay close to their father. How romantic is that?

Going back to astronomy, the Pleiades is an open cluster (a group of stars formed from the same cloud of gas and dust) located approx. 440 light years from Earth, in the constellation Taurus. The cluster contains over three thousand stars (mostly hot B-type stars) although only the seven largest stars are visible to the naked eye due to the effects of light pollution. For this reason, the cluster is also called “the Seven Sisters”.

Read the full article: The Pleiades

The blue nebulosity is not directly associated to the star cluster, but it rather seems that the latter is passing through a particularly dusty region that reflects the light from the stars. It’s what astronomers call a reflection nebula.

I hope you enjoyed it, stay tuned for more!

Clear skies!

At last, the comet!

Dear friends of The Lonely Photon,

I’m sure by now you’ve all heard about the “Green Comet” or “Neanderthal Comet” that made the news early this year, and that has been roaming our skies for the past weeks.

Comets are small, icy bodies that originate in the outer solar system and become visible as they approach the Sun and release gas and dust, creating a glowing tail.

Read more here: The mysteries of outer space

Comet C/2022 E2 (ZTF) was first discovered in early March 2022, but only made its appearance in our sky in January. According to astronomers’ estimations, the comet has an orbital period of approximately 50,000 years ago, meaning that Neanderthals were still walking the Earth last time the comet came close to us. Who knows what it will find when it comes back in another 50,000 years…

Obviously, I couldn’t miss the opportunity to photograph this stunning icy body as it approached our planet, but the weather in Luxembourg has been miserable since early October, and honestly I had almost lost hope and gave up.

Luckily though, February unexpectedly presented me with the opportunity, and hell yeah I jumped on it !

Producing an image of a comet is no easy task, however. Comets move at very high speeds and require a different approach in terms of post-processing when compared to other Deep Sky Objects (DSOs).

Despite this, and a bright full Moon washing out most details, I’m very pleased with the end result. Here’s my final version of the comet C/2022 E3 (ZTF):

Comet C/2022 E3 (ZTF) shows a bright green glow around its nucleus, which is caused by the effect of sunlight on diatomic carbon and cyanogen; this is typical of comets with a high gas content.

The nucleus was estimated to be about a kilometre in size, rotating every 8.7 hours, while its tail of dust and gas extended for millions of kilometres. The comet’s brighter greenish coma, short broad dust tail, and long faint ion tail stretch across a 2.5 degree wide field-of-view.

Here’s a video of the comet, which shows the extreme speed at which these objects are moving in their orbits around the Sun.

If you can’t visualize the video correctly, follow this link: Comet C/2022 E3 (ZTF)

I hope you enjoyed it, stay tuned for more!

Clear skies!

Happy Holidays

Dear friends of The Lonely Photon,

It’s finally Christmas, the most beautiful and exciting time of the year, and we want to take this opportunity to wish you a Merry Christmas and all the best with your projects for the new year!

Thank you all for your support! Here’s a gigantic Christmas Tree-shaped cloud of hydrogen for you 🙂

This is a re-work of the Christmas Tree complex, using new processing techniques that I recently learned. Find more details here: Christmas Tree Complex

And speaking about re-works, here are two winter jewels that I also recently revisited: the Horsehead Nebula and the Orion Nebula, two iconic nebulas in the constellation Orion, the Hunter.

The Horsehead Nebula

The nebula takes its name from the thick, dark lines of dust in the centre of the image, shaped like a horse’s head. The dark nebula is embedded in a vast cloud of ionised hydrogen gas (NGC 2023), whose red glue provides perfect contrast to the image. On the left is the Flame Nebula (NGC2024), an emission nebula about 900 to 1,500 light-years away.

Read more here: Horsehead Nebula

Orion Nebula

This is a stunning, picturesque stellar nursery: a cloud of interstellar gas and dust from which new stars are born. In fact, this is the closest large star-forming region to Earth, about 1,350 light years away. Its central region hosts four massive stars known as The Trapezium – a young open cluster that illuminates the nebula.

Read more here: Orion Nebula


These, instead, are some incredible pictures of Mars (including Mars at opposition on December 8th) taken by friend and fellow astronomer Pascal Hilkens.

Take a look at his fantastic blog, it’s rich of content and amazing pictures. You can find it here: https://pascalhilkensastropage.blogspot.com/

To conclude, let me show you some pictures of the winter Sun taken this mount.

Visit the full solar gallery: The Sun

Clear skies!