Clear Skies
January 5th, 2025, 11:30 AM
Nothing beats an original catalog. Information from the source. Pristine discoverer's notes or information unaltered by later publications that often introduce, rather than take away room for interpretation. And more often than not raise unnecessary questions that cause further confusion about the origins of a DSO.
One such publication that I was on the prowl for, was the work of Swedish astronomer Sven Cederblad (https://ui.adsabs.harvard.edu/abs/1946MeLuS.119....1C/abstract). For literally over a decade, I searched the web for the book published by the observatory of Lund in Sweden (https://en.wikipedia.org/wiki/Lund_Observatory) in the year 1946, but always came up empty.
That changed in October 2022 when, on the website of an online Swedish antiquariat, I stumbled upon a book with a title that was not an exact match but close enough to take a gamble and order it. It turned out to indeed be the original Cederblad catalog. Or rather, the original book. I jumped for joy.
5626
As you may not know, Cederblad did not discover any nebulae of his own. What he did, was amass references to nebulae that had largely gone unpublished. A great many objects were discovered in the early 1900's, but not all made it into Dreyer's work, or were discovered after publication of the NGC and IC. There are plenty of papers out there in which research was published, that also contain notes pointing to someone's discovery of object so-and-so at position there-and-there. Never to make it into any proper catalog. Cederblad set the record straight for many such discoveries. His book can by all means be regarded as a benchmark for publications on nebulae.
With the book finally in my possession, I was able to determine that the information in Vizier (https://vizier.cds.unistra.fr) for Cederblad's work is indeed a match for the catalog information in the book. I emphasize 'catalog information', as Cederblad's work includes a further 125 pages. Also: Vizier is a labyrinth and a good one at that. It continues to amaze me how some seem to truly make an effort to make information as hard as possible to extract from a website.
Cederblad's book held another surprise in stock. Tucked between the pages was a newspaper clipping. A short article + image published when Cederblad and fellow PhD graduate Sjöstedt earned their doctorates, which they celebrated by hopping over a bench.
5627
"At the doctoral graduation ceremony in Lund, mentioned in yesterday's issue, there were, among others, two well-known athletes who were promoted, the Allsvenskan (https://en.wikipedia.org/wiki/Allsvenskan_(men%27s_handball)) handball player Sven Sjöstedt (https://sv.wikipedia.org/wiki/Sven_Sjöstedt) to the degree of med. dr. and MAI (https://en.wikipedia.org/wiki/Malmö_AI)'s seven-meter long jumper Sven Cederblad to the degree of phil. dr. Here they are seen jumping for joy over a bench. You can read about the Uppsala graduation ceremony on page 9."
That hop ought to have been an easy one, considering Cederblad could jump seven meters... But it's not the athletics I want to focus on, rather a nebula in Auriga that is positioned optimally for observation this time of year.
The 61st entry in Cederblad's catalog is for a reflection nebula that was first mentioned in A photographic atlas of selected regions of the Milky Way (https://ui.adsabs.harvard.edu/abs/1927pasr.book.....B/abstract) by Frost and Calvert in the year 1927. One thing Cederblad made sure to do was to meticulously list his sources, referencing no less than 857 works. His 93rd source was the work by Frost and Calvert. Spend 40 bucks here (https://www.amazon.de/-/en/Photographic-Atlas-Selected-Regions-Milky/dp/0521191432), or click here (https://digicoll.lib.berkeley.edu/record/286050?v=pdf) to get your hands on it for free. It's on plate 7's bottom-left corner of that publication where we find the nebula. It's for that plate that the book contains the note:
"There is a small nebula or nebulous star (No. 155) in alpha = 5h56m30s, declination = +30d30m, near the lower left edge of the plate. This seems to be B.D.+30 1096. It is not listed in the N.G.C."
The second reference is for the 1934 publication Atlas of the Northern Milky Way (https://ui.adsabs.harvard.edu/abs/1934anmw.book.....R/abstract) by the same authors. Can't find it online, though.
From Cederblad's book:
5628 5629 5630
The position in J2000.0 is 06:04:36 +30d30m00s, in the southeastern part of the constellation of Auriga. The nebula is approximately 5 minutes of arc in size and surrounds the mag. 10.7 star TYC2419-01158-1. It's clearly brightest in a fan-shaped part directly northeast of the star. To the southeast is a small, detached part surrounding the mag. 11.7 star TYC2419-00855-1.
After Cederblad published his work, the nebula made it into Struve & Straka's work as their nr. 50, with the note of it being in a dark lane or nebula (that would be Lynds (LDN) 1557). Beverly Lynds herself added the nebula to her list of bright nebulae (LBN) as nr. 823. Sydney van den Bergh noted the illuminating star to be embedded in the nebulosity, which he found to be bright and moderately blue with moderate absorption. Nr. 65 in his catalog. Rojkovskij & Kuchakov added it as their nr. 46.
5631 5632
Click here (https://clearskies.eu/csog/downloads/dsfootw2025/#1) to download the guide. Click here (https://clearskies.eu/csog/downloads/nebulae#cederblad) for all Cederblad nebulae as a CSOG 3.0 (https://clearskies.eu/csog/csog30notes/) edition.
In my log (https://clearskies.eu/astronomy/observing/observinglog/) there's one entry for this object. Observed from northern France in January 2020 (https://clearskies.eu/astronomy/observing/sessions/sessions2020/20jan2020/) under not too dark skies but thankfully in a night when the transparency was truly good. My note for the observation tells me I only observed the brightest part of the nebula in my 14" SCT @ 168x / 29':
Using AV a very faint, NW-SE elongated glow is visible to the NE of a mag. 10.5 star in the tip of a small, elongated triangle of stars pointing NNE.
I missed the small, detached nebulosity to the southwest. I think it’s up for grabs in my aperture under better skies.
For your own hop (see what I did there..?) Kappa Aurigae provides for a good starting point. Our OotW is exactly 2.5 degrees to the west-northwest.
In the vicinity:
There's more going on nearby. 15' To the south is the quite wide double star STF834 (https://clearskies.eu/csog/downloads/doublestars#struve) (WDS06046+3014 (https://www.stelledoppie.it/index2.php?iddoppia=23087)) whose primary shines at magnitude 8.6. About 20' to the southwest is a pair of nebula: the very faint emission nebula Sharpless 2-241 (https://clearskies.eu/csog/downloads/nebulae#sharpless) with the smaller, but brighter reflection nebula Struve-Straka 49 on its northeastern edge. Just 5' west-northwest of the emission nebula is a truly tiny nebula (or galaxy) that goes by PGC135933. That ought to be a tough one, even for very large scopes.
For sake of completeness, here are links to the corresponding Cederblad data in Vizier: Note (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a57bb31d567&-out.add=.&-source=VII/231/notes&recno=307) - Ref. 93 (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a55cb300400&-out.add=.&-source=VII/231/refs&recno=172) - Ref. 630 (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a55cb300400&-out.add=.&-source=VII/231/refs&recno=1108)
Well, you know what to do... get out there and be sure to report back!
One such publication that I was on the prowl for, was the work of Swedish astronomer Sven Cederblad (https://ui.adsabs.harvard.edu/abs/1946MeLuS.119....1C/abstract). For literally over a decade, I searched the web for the book published by the observatory of Lund in Sweden (https://en.wikipedia.org/wiki/Lund_Observatory) in the year 1946, but always came up empty.
That changed in October 2022 when, on the website of an online Swedish antiquariat, I stumbled upon a book with a title that was not an exact match but close enough to take a gamble and order it. It turned out to indeed be the original Cederblad catalog. Or rather, the original book. I jumped for joy.
5626
As you may not know, Cederblad did not discover any nebulae of his own. What he did, was amass references to nebulae that had largely gone unpublished. A great many objects were discovered in the early 1900's, but not all made it into Dreyer's work, or were discovered after publication of the NGC and IC. There are plenty of papers out there in which research was published, that also contain notes pointing to someone's discovery of object so-and-so at position there-and-there. Never to make it into any proper catalog. Cederblad set the record straight for many such discoveries. His book can by all means be regarded as a benchmark for publications on nebulae.
With the book finally in my possession, I was able to determine that the information in Vizier (https://vizier.cds.unistra.fr) for Cederblad's work is indeed a match for the catalog information in the book. I emphasize 'catalog information', as Cederblad's work includes a further 125 pages. Also: Vizier is a labyrinth and a good one at that. It continues to amaze me how some seem to truly make an effort to make information as hard as possible to extract from a website.
Cederblad's book held another surprise in stock. Tucked between the pages was a newspaper clipping. A short article + image published when Cederblad and fellow PhD graduate Sjöstedt earned their doctorates, which they celebrated by hopping over a bench.
5627
"At the doctoral graduation ceremony in Lund, mentioned in yesterday's issue, there were, among others, two well-known athletes who were promoted, the Allsvenskan (https://en.wikipedia.org/wiki/Allsvenskan_(men%27s_handball)) handball player Sven Sjöstedt (https://sv.wikipedia.org/wiki/Sven_Sjöstedt) to the degree of med. dr. and MAI (https://en.wikipedia.org/wiki/Malmö_AI)'s seven-meter long jumper Sven Cederblad to the degree of phil. dr. Here they are seen jumping for joy over a bench. You can read about the Uppsala graduation ceremony on page 9."
That hop ought to have been an easy one, considering Cederblad could jump seven meters... But it's not the athletics I want to focus on, rather a nebula in Auriga that is positioned optimally for observation this time of year.
The 61st entry in Cederblad's catalog is for a reflection nebula that was first mentioned in A photographic atlas of selected regions of the Milky Way (https://ui.adsabs.harvard.edu/abs/1927pasr.book.....B/abstract) by Frost and Calvert in the year 1927. One thing Cederblad made sure to do was to meticulously list his sources, referencing no less than 857 works. His 93rd source was the work by Frost and Calvert. Spend 40 bucks here (https://www.amazon.de/-/en/Photographic-Atlas-Selected-Regions-Milky/dp/0521191432), or click here (https://digicoll.lib.berkeley.edu/record/286050?v=pdf) to get your hands on it for free. It's on plate 7's bottom-left corner of that publication where we find the nebula. It's for that plate that the book contains the note:
"There is a small nebula or nebulous star (No. 155) in alpha = 5h56m30s, declination = +30d30m, near the lower left edge of the plate. This seems to be B.D.+30 1096. It is not listed in the N.G.C."
The second reference is for the 1934 publication Atlas of the Northern Milky Way (https://ui.adsabs.harvard.edu/abs/1934anmw.book.....R/abstract) by the same authors. Can't find it online, though.
From Cederblad's book:
5628 5629 5630
The position in J2000.0 is 06:04:36 +30d30m00s, in the southeastern part of the constellation of Auriga. The nebula is approximately 5 minutes of arc in size and surrounds the mag. 10.7 star TYC2419-01158-1. It's clearly brightest in a fan-shaped part directly northeast of the star. To the southeast is a small, detached part surrounding the mag. 11.7 star TYC2419-00855-1.
After Cederblad published his work, the nebula made it into Struve & Straka's work as their nr. 50, with the note of it being in a dark lane or nebula (that would be Lynds (LDN) 1557). Beverly Lynds herself added the nebula to her list of bright nebulae (LBN) as nr. 823. Sydney van den Bergh noted the illuminating star to be embedded in the nebulosity, which he found to be bright and moderately blue with moderate absorption. Nr. 65 in his catalog. Rojkovskij & Kuchakov added it as their nr. 46.
5631 5632
Click here (https://clearskies.eu/csog/downloads/dsfootw2025/#1) to download the guide. Click here (https://clearskies.eu/csog/downloads/nebulae#cederblad) for all Cederblad nebulae as a CSOG 3.0 (https://clearskies.eu/csog/csog30notes/) edition.
In my log (https://clearskies.eu/astronomy/observing/observinglog/) there's one entry for this object. Observed from northern France in January 2020 (https://clearskies.eu/astronomy/observing/sessions/sessions2020/20jan2020/) under not too dark skies but thankfully in a night when the transparency was truly good. My note for the observation tells me I only observed the brightest part of the nebula in my 14" SCT @ 168x / 29':
Using AV a very faint, NW-SE elongated glow is visible to the NE of a mag. 10.5 star in the tip of a small, elongated triangle of stars pointing NNE.
I missed the small, detached nebulosity to the southwest. I think it’s up for grabs in my aperture under better skies.
For your own hop (see what I did there..?) Kappa Aurigae provides for a good starting point. Our OotW is exactly 2.5 degrees to the west-northwest.
In the vicinity:
There's more going on nearby. 15' To the south is the quite wide double star STF834 (https://clearskies.eu/csog/downloads/doublestars#struve) (WDS06046+3014 (https://www.stelledoppie.it/index2.php?iddoppia=23087)) whose primary shines at magnitude 8.6. About 20' to the southwest is a pair of nebula: the very faint emission nebula Sharpless 2-241 (https://clearskies.eu/csog/downloads/nebulae#sharpless) with the smaller, but brighter reflection nebula Struve-Straka 49 on its northeastern edge. Just 5' west-northwest of the emission nebula is a truly tiny nebula (or galaxy) that goes by PGC135933. That ought to be a tough one, even for very large scopes.
For sake of completeness, here are links to the corresponding Cederblad data in Vizier: Note (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a57bb31d567&-out.add=.&-source=VII/231/notes&recno=307) - Ref. 93 (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a55cb300400&-out.add=.&-source=VII/231/refs&recno=172) - Ref. 630 (https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-ref=VIZ677a55cb300400&-out.add=.&-source=VII/231/refs&recno=1108)
Well, you know what to do... get out there and be sure to report back!