Clear Skies Observing Guides

New Editions

With the publication of CSOG 3.0, on 29 November 2024, 20 new editions were added. Where applicable, new objects and new or updated information was incorporated into existing content.

The new nebula editions bring further unique content to CSOG. These editions will appeals to both observers and astrophotographers alike. For these catalogs, the objects they contain and for their proper "historically first" designations, the record is finally set straight, after many decades. This information - as goes for most CSOG content - is not available in any other publication.

Since CSOG 3.0 was published, 9 more editions were added, as indicated below.

Updated Content

CSOG 3.0 is in essence a complete rewrite: there is not a single file that was not edited. A lot of changes were also made 'behind the scenes', allowing for much easier updates from now on;
For every galaxy in "by object" guides that is within the SDSS footprint, an SDSS image was added in addition to the DSS images that were already part of every observing guide. These images add a lot of useful detail, especially to the many galaxies in the Herschel edition and the Herschel 400, Herschel II, Herschel 3 and the new Herschel Sprint observing programs filtered from it;
"By object" guides (one object, one guide) were added to the Melotte, Raab, Trumpler and Collinder star clusters editions. Other star cluster editions will follow;
Countless updates to and corrections of existing content, along with lots of cosmetic tweaks;
Many objects added, for example, in addition to the new editions: 295 objects added to the Named Objects edition, 798 objects added to the 12-14" Constellation edition... and much more;
For every download, the number of included observing guides & the number of pages, the index files, planfiles and tourfiles is now displayed.

CSOG Statistics

89 Editions, 2 observing aids and the "Periodicals" (Objects of the Week / Month / Season);
1.3 terabytes of content;
14513 unique observing guides (42903 pages) and 607 index files (2836 pages);
574 unique AstroPlanner planfiles;
4205 unique Autostar Tours, NexTours and EQTours;
4681 unique Argo Navis User Catalogs.

The Size of CSOG

CSOG is a digital publication, intended to be used on a computer (for planning and logging) and on a properly filtered and dimmed tablet at the eyepiece of the telescope. CSOG will not exist in print, unless a publisher wishes to create books for specific editions; that, of course, only with my permission and appropriate compensation.

The following analogy gives a good impression of the size of CSOG:

Say, one was to in fact print CSOG. All editions as of 9 April 2025, including all index files. No mirrored editions, only the unmirrored ones. Printed once, double-sided; some guides and index files have an odd number of pages, which would leave blank pages at the end, but for the sake of argument let's say every page were to be filled.

Given that, per the image to the left, a pack of 500 pages is 5.3 centimers (2.09 inches) in height... how high would the stack of paper be for all CSOG editions printed (every edition and every index only printed once, no mirrored content)?

43011 pages in the observing guides + 2836 pages in the index files = 45847 pages. Printed double-sided that would fill 22924 pages front and back. Divided by 500, that is 45.8 packs of paper. Multiplying that by 5.3 centimeters (2.09) inches tells us the height of the stack for all of CSOG (unmirrored) printed once, including all index files, is 2.43 meters (8 feet).

Were one to print all mirrored content, too, making sure to print the index files and the unmirrored binocular editions only once, the height of the stack would be 9.18 meters (30.1 feet).

That is the size of CSOG and that is why it does not exist in print.

Due to the sheer size of the publication, CSOG 3.0 was the last release in which every edition was updated simultaneously. From here on, there will be interim updates to existing content in addition to publication of new editions.

Registration & Support

To download the Clear Skies Observing Guides, registration and a support donation is required: a modest fee to support the creation and publication of CSOG.

CSOG is a one-man-show, created, hosted and self-funded by Victor van Wulfen. It cannot exist without support.

Support donations will offset only a fraction of the time, effort and costs that have gone into creating CSOG, since the year 2001 and in its current form, since the year 2008. There is no profit and unless literally thousands of support registration will pour in, there never will be a profit.

As of the publication of CSOG 3.0 on 29 November 2024, registration and a support donation gains access to all CSOG downloads and any new editions and updated content for the period of one year (365 days) after the day of the support donation. That ought to be plenty of time to download all CSOG editions and any new content published within that one year, in all image orientation options. Once the year has expired, a new support donation will be required to continue to have access to the downloads for another year.

Registrations for CSOG 2.4 were deleted and a new registration and support donation is required for CSOG 3.0.