Any members reading this have surely shot the moon. Most start with the full moon, doubtless because there is some intrinsic romanticism associated with the full moon. Then we graduate to the first quarter moon when it is pointed out that full moons have poor contrast and bad light, similar to noon-time light on Earth.
At some point you might feel like you have had your fill of the basic moon shots then you may want a new challenge. That challenge is the chasing of both new and old moons. This is arguably best done with a pair of binoculars and any moderately long lens, such as a 70-200 or 70-300. No motorized mounts are needed and very long focal lengths are not necessarily optimum or even desirable.
Best of all, very new and old moons are by definition very close to the horizon at dawn or dusk and therefore make great landscape shots.
Most people have seen a 2 day old moon, just after sunset to mid-dusk. It appears as a slender crescent. That is an easy shot. We are going to concentrate on moons near 24 hours from new, and the closer to new the better. The challenge is to shoot the oldest and newest moon possible.
Very few people have seen a 24 hour old moon and fewer have seen an old moon 24 hours or less from new. A visual sighting might require binoculars to pick the dim moon out from the bright dawn or dusk sky and you have to know when and where to look.
Like the romanticism that has grown up around the full moon, the new moon seems to generate far more interest than old moons. Sky & Telescope magazine will occasionally run an article about chasing new moons but I dont ever recall an article promoting old moons.
My Lunar Phase Pro software provides me with a chart of all upcoming new moons, but not old moons. That I have to research myself . I always try to march to the beat of a different drummer so I am giving old moons equal time here. Plus, it gives us something to chase in the new moon off season.
Some Celestial Mechanics
More so than normal moons some knowledge of the orbits of the earth and sun are required.
The sun follows a path through the celestial background called the ecliptic. It makes one full revolution roughly once every 365 days. The fact that it is actually 365.25-something days results in leap years and occasional leap seconds.
The ecliptic is tilted such that it is highest in the sky at the summer solstice and lowest at the winter solstice, giving us our seasons.
The planets orbit around the sun, more or less following the same path but all are slightly tilted relative to the ecliptic, presumably due to catastrophic events in distant epocs. As a result, planets will generally appear some number of degrees above and below the ecliptic.
The moon orbits the Earth, of course, and its orbit is tilted about 5 degrees from the ecliptic, such that at any time it may appear as much as 5 degrees North or South of the line of the ecliptic and this is a critical aspect of chasing these moons.
All phases of the moon have seasons. These seasons are fixed to the calendar. In the Northern Hemisphere, December is the optimum month to view a full moon and June is the poorest. That is because the full moon is opposite the sun and when the sun is lowest in the sky in December the full moon is on the high side of the ecliptic, opposite of the sun, where the sun will be in June.
The first quarter is best viewed around March and the last quarter best viewed around September.
Picking the right time of year to view any normal phase of the moon is a simple matter. In the Northern hemisphere, simply view the moon when it is furthest north along the ecliptic. That furthest north point of the ecliptic is always in the area of the constellations Taurus and Gemini.
Very new and old moons are quite different and more complicated.
Because the moons orbit is tilted relative to the ecliptic, there can be better than average optimum seasons for the moon. But if the moon is 70 degrees above the horizon at optimum, whats another 5 degrees, plus or minus? There are more or less favorable seasons for any phase of the moon in any given year but we are generally unaware of it unless we carefully study astronomical ephemera.
When chasing new and old moons, though, every degree counts! And for that reason we must obsess over more or less favorable positions of those moons. Some years are just not good years, where other years are more favorable. This makes the challenge frustrating at times, but all the more satisfying when accomplished. It also means that these opportunities are fleeting and far between.
Edit: The US Naval Observatory has a very interesting web page here, concerning earliest possible visible crescent moons, and is well worth reading. The short story perhaps is that you just need to go out and look . The subject of the newest possible visible moon is an extremely complex matter.
The September 15, 2012 Old Moon
Below is a map drawn from SkyMap Pro V10. The lines are altitude and azimuth (not astronomical right ascension and declination). The upper blue area ends at the physical true horizon. I have added a few annotations in red.
Old moons are rather complex because, for example, in this case the moon is 28 days 18.72 hours old, but is 15.53 hours from new. Ive never seen astronomical software that provides the old moons age counting back from the new moon (another example of that bias toward new moons).
The length of a single lunar orbit around the Earth (a lunation varies. For that reason the age is not terribly useful. We care about the length of time until the upcoming new moon.
The map was drawn as of 6:38am EDST, positioned on the Maryland coast where I would go if I wanted to view this. The new moon occurs at the same time all over the world. In this case, at 10:10pm EDST on Sept 15.
Members in London, GB will experience the same sunrise 5 hours earlier so their old moon will be about 20.5 hours from new. Members on the West Coast USA will see a 12 hour moon- a very daunting task.
From the above you can conclude that somewhere in the world we see whatever age moon we want, but in any given place we have to take what is handed to us. The age of any given old or new moon, only visible for an hour or less, is purely dependent on the exact time of the new moon, which varies without much obvious pattern from month to month.
A moon less than 24 hours from new is tough. The record is somewhere around 10 hours, as I recall, and that would be done at a certain place on Earth for a very favorable moon (specific to that event), and usually from a high altitude. To see something like that you would likely have to chase it like a solar eclipse, with all the attendant time and expense involved in those pursuits.
For us mere mortals, I suspect that 16 hours may be a practical limit and I think quite an accomplishment. At this point in time that happens to be my own personal reasonably achievable" goal - a 16 hour moon- new or old. If I lived at altitude I might have a more ambitious goal.
On the map below we see the sun just rising, with the moon to upper right. The moon is just about 5 degrees above the horizon and would definitely not be visible as the sun rises. It is too dim, too delicate an image.
Here is the big question: will the moon rise out of the typical murk on the horizon and be visible before its very delicate light is washed out by the brightening dawn? On any given day and conditions that answer may vary. It's a closely contested horse race!
The moon lies about 4 degrees south of the ecliptic, and that is the problem here, and everywhere in the world on that morning. I have drawn a line perpendicular to the ecliptic, and about centered on it. That line roughly represents the approximately +/-5 degree possible placement of the moon relative to the ecliptic. Here it is well south and South is always unfavorable.
As mentioned, this unfavorable old moon is only 5 degrees above the horizon. If it were 5 degrees North of the ecliptic it would be about 8 degrees above the horizon and that is a HUGE 3 degrees! That might double or triple the odds, or even just make it possible.
I wont say this moon is impossible but we have about the worst possible placement on the ecliptic during what is otherwise a very favorable time to view old moons. Members in Europe or even east of Western Europe would have a progressively easier time of this but then again, they would be viewing a 20-24 hour moon, which is not nearly as difficult, all else equal.
In the Northern Hemisphere the
new old moon season spans approximately late summer to early fall. The new moon season spans roughly January to May.
You will note that the ecliptic rises steeply, and if the moon were well placed it would be directly above the sun or could even be slightly North of the sun. That is what you ideally want.
A shallow ecliptic, rising not as steeply, is unfavorable for reasons that should be obvious and shortly will become more obvious. In the spring, the old moon sits on a very shallow ecliptic.
The September 16, 2012 New Moon
To recap, on the morning of Sept 15th we have a less than 24 hour old moon. At 10:10pm that evening (East Coast USA, EDST) we have the new moon, where if the moon were placed precisely on the ecliptic we would have a solar eclipse. As we have seen, the moon is far from the ecliptic so no joy there.
On the evening of the 16th the sun will set at about 7:01pm EDST on the East Coast USA and by then the now new moon has passed the sun and is 20 hours and 49 minutes old. In principle this is easier to see because it is 5 hours further from the sun than the old moon but it isnt that simple .
And we can see below, the ecliptic is very shallowly inclined and the moon is still about 4 degrees south of the ecliptic. That is a doubly unfavorable new moon. As you can see, it will set only a few minutes after the sun, making it impossible to view.
A similar situation can occur with the old moon in the spring when the angle of the ecliptic relative to the horizon is similarly shallow around the location of the old moon.
I have, again, drawn a line perpendicular to the ecliptic to illustrate where, with some luck, the moon might be well placed. If this new moon were sitting at its maximum 5 degree travel north of the ecliptic then it would be at about 10 degrees altitude at sunset and would be very viewable in good weather.
From that I have concluded that in truth the position of the moon relative to the ecliptic is more important than the season. And that is counter to what I have always read in the past, where the seasons (with the ecliptic sharply angled into the horizon) are emphasized.
In terms of seasons, it is important to understand that while the new moon is in the furthest north ecliptic region (Taurus-Gemini) around mid-May to early June, the tilt of the ecliptic is most favorable around March (with the straddling months also very good). That assumes a similar positioning of the moon perpendicular to the ecliptic, as previously stressed.
Below is my favorite new/old moon image. This was shot March 16, 2010 at 7:31 EDST when the new moon was 26 hours old. I include this image not just to illustrate how the new moon can be incorporated into a landscape but also to illustrate that, amazingly enough, it can be visible right down to the horizon.
And it is obvious that I did not even have a clean horizon although it did add greatly to the image. Twenty minutes before I shot this I would not have wagered 10 cents that this image would happen. I was amazed.
The point I am making is that if the circumstances present themselves always try to shoot the new and old moons. Dont let anyone (or yourself, or me!) talk you out of it .
This next image is an old moon, about 29.5 hours from new, shot on March 25, 2009 in the worst season for the old moon. The moon was about 2 degrees north of the ecliptic (not ideal, but a 7 out of 10 if you think about it). The moon was probably within a degree or two of the horizon, at least according to my camera EXIF and I do try to keep my camera clocks very accurately set just for this purpose. It was slightly under 7 degrees altitude at the moment of sunrise, long after it would have disappeared into the glare of the increasingly bright dawn sky.
Interestingly, this is the oldest moon Ive shot, based on age from the prior full moon, but I have two old moons closer to the new moon and therefore, by my way of thinking, more desirable. That was due to the March 2009 lunation being on the long side. I previously mentioned that the periodicity of the moons orbit varies a bit.
And I have to add my crowning achievement so far in this venture, 20 hours 40 minutes from new .
This image was shot April 25, 2009, at 8:14pm EDST, with a very favorable steep ecliptic (remember new moon in spring!).
I was also blessed with a moon 4 degrees north of the ecliptic, so this was about as good as it gets. I only regret that it wasnt a couple hours earlier because these are the conditions needed to get a truly new moon- something approaching 16 hours.
Here the moon is about 5 degrees above the horizon, with the sun about 5 degrees below the horizon. The moon was directly above the sun- it just doesnt get any better than that.
I found the moon with binoculars and as I recall I got my first shot at 8:03:54pm, within a minute or two after my visual sighting. I recall that when I got that first shot the moon was not yet visible naked eye but it was very dimly visible in the viewfinder (a very important observation!).
My last shot was at 8:18pm and I suspect it went into the murk at the horizon. I typically try to get my first and last possible shots just for documentation and future research. There are many questions about how close to the horizon, how close to the sun, and etc. Good records are helpful when planning future conquests!
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#1. "RE: Chasing New and Old Moons" | In response to Reply # 0
avm247 Charter MemberThu 13-Sep-12 04:18 AM
Thanks for the thread, Neil, gonna try and shoot some soon. I caught a waning crescent this morning with Venus after re-reading this post a few days ago. They were closer together in the morning but moved quite a bit by the time I got home and got my gear set up before going for a morning swim.
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#2. "RE: Chasing New and Old Moons" | In response to Reply # 1
Thu 13-Sep-12 12:39 PM
Looking forward to your first/last moon shot
I need to point out that in my above tome I have some ambiguity in definitions.
Technically, the "New Moon", in an astronomical sense, is a precise moment in time that marks the start of a lunation. A lunation encompasses the time between successive new moons. The astronomical new moon is the moment in time when a solar eclipse would occur if the moon were placed precisely on the ecliptic. In most cases it more or less happens when the moon is closest to the sun.
Wikipedia defines it as "the moment of conjunction in ecliptical longitude with the Sun". I'm not a cartographer so don't ask me to explain that in plain English .
It is also common to call the first visible (or theoretically visible?) moon of a new lunation the "New Moon".
If the astronomical new moon occurs 3 hours before sunset then the "first moon" occurs 3 hours later, around sunset but is impossible to view. The first truly visible moon would be 24 hours later, or about 27 hours old. Which moon is the "first moon"? I point this out just to emphasize that some of these definitions are difficult to pin down.
I unfortunately used "New Moon" to describe both points in time . Hopefully that did not create too much confusion. I know what I meant, hopefully everyone here will too .
It is probably better to use the terms "first moon" and "last moon".
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#3. "Where to shoot these moons..." | In response to Reply # 0
Although my post was far longer than it should have been, all I covered was how to identify the relative favor-ability of these events. I think that is the most important piece of this puzzle because most people can't view this from their backyards. I have a 3+ hour drive to my favorite site.
I left out a number of subjects, which I'll try to cover in a few follow-up posts.
These moons will always be viewed within 10 degrees of the horizon. Your clenched fist, held at arms length, thumb facing up (but not extended), spans about 10 degrees and one finger spans about 2 degrees.
It would be rare to view a moon within 24 hours of new at more than 5 degrees above the horizon. It is always a race against time. If it were easy I would not have written such a long post above . Some of the moons I've viewed were within 2 degrees of the horizon when first seen.
There are two obvious choices:
1. From a beach at a coastal area or large lake with water that extends to the horizon (in the USA maybe the Great Lakes). Some elevation is also very helpful (e.g., a balcony with an east or west view).
2. From a high vantage point such as a mountain top and in this case it needs to be the tallest mountain in the direction of viewing. Could also be a balcony on a tall building well above any nearby buildings or terrain.
Generally speaking, high altitudes = cleaner air, so altitude is favored. I suspect most "earliest first moon" records were set on mountain tops well above 5000 ft altitude. There is a reason that the world's major astronomical observatories are all on the tops of tall mountains and those reasons coincide with our needs here.
I don't live near any mountains so I use a coastal area. I live in an area of gently rolling terrain, such that views to the true horizon are rare. I know of no nearby public areas with such a view (and open at the appropriate time), nor do I have any nearby friends in high places that live on such a high vantage point.
I have access to a 22 story building at the coast, which gives me an essentially flat horizon to the east and west, the inland view being over the flat coastal plain. The distant treeline is miles away, on the other side of a bay, so my inland horizon is also near zero degrees altitude. Aside from weather issues it is perfect.
The problem with most public parks and etc., at least where I live, is that typically the hours are sunrise to sunset, which neatly puts our viewing window about a half hour to an hour on the side of trespass.
Some wildlife refuges are open "dawn to dusk" but I've been booted out of Chincotague NWR a bit before what I consider "dusk", at least in the technical sense. There is, very technically, a precise moment of "dusk" and "dawn", but try arguing that with a refuge ranger. In other words, "dawn to dusk" access is not necessarily reliable for our purposes here.
Public areas such as parks, especially small local community parks, often have strict rules to minimize beer parties and vandalism but are more flexible for "insiders". A little volunteer work at that park can make you an insider. That is an angle I work on just for my birding. But I have't found a small local park with the view I need for this work.
Marine environments are very problematic due to the "marine layers" that tend to accompany any offshore wind or stagnant air. But in my case that is the best I can come up with. A large inland body of water would be better, large enough to essentially stretch to the horizon but not so large as to create a serious marine layer micro-climate.
Good luck on that one. I think location is the toughest part of this puzzle and I certainly have never found an ideal solution.
An accessible vantage point, with views to the east west and south, is golden for many astronomical events other than chasing newest and oldest moons. There are many astronomical events that require a clear view of the horizon. Examples include comets, or just things that happen, such as occultations, that occur in brief instants that may happen to occur in your locale near the horizon.
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#4. "Exposure..." | In response to Reply # 0
Finding the right first or last moon may appear to be rocket science, but the exposure is a bit easier:
1. Mount camera on tripod.
2. Set camera on some Auto Exposure Mode
3. Fire. Preferably with a remote to eliminate camera shake.
OK, there is a little more to it, but basically any moon within 30 hours or so of new will be only a thin sliver with no discernible detail.
In most cases it will not be "dark", to the extent that these events usually occur within civil twilight or near nautical twilight. It is the typical pre-sunrise or post-sunset type of sky where there is usually a lot of color in the sky. The sky will usually determine the exposure.
The moon, in most cases, will not "burn" but I would suggest watching the blinking highlights display just to be sure, and reduce exposure if the moon blinks at you.
In the case of a wide angle landscape shot, the landscape will determine the exposure and hopefully the moon will fit in. And in most cases it will.
In truth, and the whole point of all that previous rocket science, is that you are lucky to even see or image these moons. It would be rare indeed to have excess moon brightness.
The above is not true for a 2nd to 4th day crescent moon, where at long focal lengths there is some crater detail and the moon is progressively further from the sun, setting about 40 minutes later each day.
In that case it may take some thought unless you are content to let the moon burn. As with all celestial landscape photography, it is best done when the brightness of the sky fairly well matches the brightness of the moon. And, for many reasons, that tends to favor a 2nd day moon (centered around 48 hours of age) for a nice dusk landscape shot with crescent moon.
By the 3rd or 4th day the moon is very high when the light is right, requiring wide angles that make for tiny moons. By the time the 3rd or 4th day moon is near the horizon it is often too dark and then multi-frame HDR or some other rocket science is required. That rocket science might include graduated ND filters, which are also very useful for full or near full moons rising and setting but a bit bright.
ND filters will tend to throw ghost images when presented with a bright crescent moon but that is why they made cloning tools!
For all those reasons, the first and last easily visible moon is the moon I usually try to incorporate into landscapes when I want a crescent moon in the image.
An ISO as close to base ISO as possible is always preferable. I follow the guidelines in my Celestial Movements post (pinned to the top of the forum) to determine the minimum shutter speed I want. I may allow a few pixels of blur because there is no detail on these thin crescents, but not too many pixels. A fuzzy crescent is also undesirable.
I also try to find something suitable for about 200mm (FX) focal length in order to reduce the rate of movement per second. The DX comparable would be about 135mm. The landscape posted above is 220mm FX (at f/4) and that is just about perfect in my book, in terms of the size of the moon I want. If much smaller it does not have the effect I want- it becomes a bit player in the scene. Any larger and I have increasing motion and depth of field problems.
Obviously that is all according to personal taste and some scenes can and should be shot at longer focal lengths. I just find those scenes difficult to come by considering the rarity of nice landscape scenes that also extend to the horizon such that the thin crescent moon is even visible.
Some of the most interesting lunar imaging I've seen involve very long focal length images of moons setting or rising just above mountains but that is not my lot in life. This can also be done with the moon near a nicely silhouetted tree or other closer subject of interest although the depth of field issues can be daunting. The distance from camera to tree must be closely coordinated with the size of the moon and DOF at the required focal length.
Shooting at or near wide open may be important to control shutter speed and in that case I try to avoid depth of field issues. The image I posted above, with the gazebo over the bay, is an example of where I try to keep things simple, and eliminating close subjects that would also need to be in sharp focus. Just a few ideas that I have; if you can figure out a way to stop the moon, get a large enough moon to be interesting, and include close subjects of interest, and get it all in focus then go for it
That last idea begs for a post discussing the distance formulas, where you can calculate ahead of time the apparent size of a given subject, at a given distance, in the frame relative to another subject such as the moon.
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#5. "The cycle of favorable new moons" | In response to Reply # 0
This issue of cycles is a complex subject. I've never seen a comprehensive discussion in the context of the thin crescent moon chaser.
The answer seems to lie in the Eclipse literature, where certain cycles of the moon that directly effect the cycles of eclipses also relates to our problem here.
A good book on the subject is "Totality - Eclipse of the Sun", by Mark Littmann and (the late and sorely missed) Ken Wilcox. Ken was one of the most kind and sharing persons I ever met. I had the opportunity to shoot a total solar eclipse with him, Mark Littmann and Fred Espanak of NASA. My copy, signed by Mark and Ken, will always be a treasured memento of that event.
The short story is that the tilted orbit of the moon precesses on a roughly 18 year cycle. While the moon goes through a complete cycle, plus/minus 5 degrees relative to the ecliptic, each lunation (AKA a synodic month), it always returns to almost exactly the same position at the same phase. That "almost" is the 18 year cycle.
The most favorable part of the monthly lunation will slowly drift backward in the calendar on an 18.6 year basis. Any given month, over several years, will slowly get better or worse.
Right now the spring is the "good time" and the fall is the "bad time". By around 2015 the January new moon will be furthest north, rather than around march as it is right now.
As I mentioned in my first post, I have come to the realization that, for example, the fall is now and for the next several years very unfavorable in terms of the new moon's position relative to the ecliptic, yet the fall is when the last moon of the lunation (the oldest moon) should ideally be shot. That because of the sharp tilt of the ecliptic that time of year at the new moon.
But the geometry is such that it may be that the spring is the best time to shoot both old and new moons although old moons are at a disadvantage and won't be fully favorable. And this will be true for many years to come, with a one month adjustment every year or two to keep up with the cycle.
Looking out past 2015 we will have a run of years where the spring and fall sharply tilted ecliptic will be accompanied by "neutral" favorability in terms of the new moon's declination.
During that interval some of these moons will be shot but records will not likely be made, not by the Truly Devout looking for that 10 hour old new moon, nor us trying to simply beat a past personal record.
Unfortunately for me, spring here is the cloudiest and wettest time of the year. The odds of the weather required to shoot a 24 hour moon could be as bad as 1:10 that time of year, and certainly worse than 1:5. But nobody ever said that pushing the astronomical envelope was easy...
In about 7-9 years the situation will reverse, with old moons very favorable in the fall, and we may have to shoot the first (new) moon in the fall despite our ideal desires.
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#6. "RE: Chasing New and Old Moons" | In response to Reply # 0
#7. "RE: Chasing New and Old Moons" | In response to Reply # 0
love this idea...new challenge to try. Have you tried using The Photographer's Ephemeris? I was told about it by a local photographer, and have found it to be accurate and extremely helpful! It helps take out some calculations on when, and where to be able to see the moon or sun rise/set. Loved the photo of the moon right on the horizon! Beautiful!
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