March brings the vernal equinox, hopes of improved weather and the possibility of a marathon road trip across the sky through Messier’s list of astronomical objects. Note: it is not a “messy” list.
The strange background to this very old list (~1774), published by the French astronomer Charles Messier (powered by Pierre Méchain), is that it begins as a list of “annoying” objects that can be mistaken for comets. Messier was a comet hunter who used a 4” (100mm) aperture refractometer and had 13 recorded comets. Of course, the comet hunt was done intuitively from Paris, France, since photography hadn’t been invented yet. Accordingly, the objects on the list are mainly those that are easily visible to the human eye through small telescopes, and largely ignore the dark red hydrogen-alpha clouds that are so evident on the photographs. Modern sky photo.
The Visual Challenge of Marathon Messier
Because the objects in the Messier catalog are easily visible to the naked eye even with modest amateur telescopes, an annual activity for astronomy clubs is the “Messier Marathon” challenge. mid-to-late March, during which there was a period when all 110 jumbled objects could be seen in one night. However, success in a marathon depends on ideal conditions:
- Clear sky all night
- Reasonably dark sky
- North Latitude (~20-40 degrees North)
- At or near New Moon
- A good supply of hot coffee
Also, if the objects are not viewed in the proper order, not all of them can be seen as some will soon set after sunset, and others will rise just before the Sun. The order of viewing these constraints is published by Don Machholz (an American comet hunter) and others and also available as a brief person Messy Sequence List (PDF) online at ‘s website Astronomical Society of Rio Rancho (New Mexico). The sky view sequence path can be seen below based on the sky chart assembled from Stellarium conspiracies.
Because many Messier objects are grouped together, an enlarged view of several crowded areas is shown in the following supplemental chart. Click on the image to see larger views.
This year (2022), the Moon phase is not optimal, occurring at the end of March, so this year is not the best time to try this, but any clear night is possible” practice” and encourages familiarization with the night sky. It goes without saying that completing the Messier Marathon is quite an achievement and pleases the competitive ones. And of course, you’ll get much more out of it if you can do it without a computerized telescope!
Photo challenge
Visually, completing the Messier Marathon in one night is nearly impossible, although amateur teams have managed to do it with automatic telescopic mounts. The challenge is that the objects consist of deep space objects and vary greatly in size and brightness. Also, on average, only a few minutes of exposure can be allotted to each target, although in certain parts of the marathon some subjects may be captured in a single field of view with the camera. appropriate telescope image and size.
An additional compromise may be needed to find the right exposure to use in time-limited conditions, especially for targets near sunset and sunrise. Choosing the size of the telescope and camera sensor is very important. A field of view that is too small can require effort to assemble a mosaic of a large target, but a focal length that is too short can make it difficult to see small targets. On the other hand, with a good combination of telescope and camera, there are several targets that can be captured in a single camera view with the appropriate framing.
Appliances
One goal might be to use the same size of telescope that Messier used (4”/100mm objective). You may want to use a Barlow lens or 2x remote adapter to increase magnification on small targets at the cost of time reconfiguring and refocusing your telescope, but to start, choose a fixed telescope setup, shoot at the main focus and use your normal camera to see what you can capture.
Use short exposures (30 seconds or so) and shoot multiple exposures for more depth if needed, and avoid using automatic controls that will slow your progress on the Messier list.
Since Messier objects are visual objects (our eyes are more sensitive in the dark to green wavelengths), a DSLR (or mirrorless) camera will do just fine. Only a few Messier objects glow by Hydrogen-alpha’s deep red light (e.g. M42 and M8), and these objects are luminous and also glow with Hydrogen Beta and Oxygen III components, both at the tip. blue-green color of the spectrum. To shoot both smaller and wide-field targets, use a full-frame, high-megapixel camera (I use Nikon D850 or modify Canon RP) is more appropriate.
Planning
Obviously, planning is the key to success in photographing Messier subjects. I recommend using Stellarium (free) or similar desktop planetarium software to plan your shots in advance. Stellarium has the ability to overlay a camera frame based on your input focal length and camera size so you can visualize each shot in advance and adjust your expectations, and help you compile your shooting sequence as you go. move along the marathon route. Stellarium also has the convenient ability to display only Messier list objects in the sky, as well as providing assistance in locating a target by simply typing in the specified Messier object.
Listed Messier
Without a doubt, planning ahead is essential for a true Messier marathon! But there’s no need to dive into the depths and stress of doing this during a one-night marathon. We can easily make it happen by turning it into a yearlong project of Messier list photography. With experience, a photographic marathon can be done for several nights in a row. No matter how you do it, the project can be a good incentive to get us out under the night sky all year long.
For detailed information about Messier objects, including size and magnitude, see Convenience, sortable table on Wikipedia.
