Declination of planet Earth

Has this changed in the past 7-8 months?

I only ask because for 23 years (more than two solar cycles) the Sun has risen over the island in the middle of the lake I live on and come beaming in through the S.E. facing window. Summer to Winter would see it move a few degrees left and right, meaning I would see it rise directly over the island during Summer months and a little to the left of the island during the Winter.
Considering I live in CT, not far South of that 45* latitude, I would anticipate a reasonable swing in location of sunrise, but expect it to stay within about 15* of arc.

This year, however, since the Winter Solstice the Sun has not reversed its travel and continues to rise further and farther to the left instead of returning to it's Summer point. Where the Sun always rose directly in front of the house it is now rising on the left side of the house. This mean I'm viewing the sun rise almost North East from my location.

Sunset is hidden from me and difficult to keep track of so I don't have true bearings on a complete path, sun rise is when I take the dog out for a walk by the lake. The lake itself gives a panoramic view and easy to tell where the sun is coming up over distinguishable landmarks like an island or a cell phone tower visible in the distance.

For what it's worth, an astrolabe in the garden still shows noon at 12:00. At that point, degree of declination has no meaning - it would be the same at the Equator as it is at 45* North. It's the rising and setting that show how far the Earth is tilted towards the Sun in it's Northern hemisphere.

On a similar note, I always used to stand out my front door in the evenings and see Orions Belt right in front of me. That familiar constellation is now almost straight up over the house, when it used to be right above the treeline it's now almost directly above.

This is a case where I know what I've seen in the past, and know what I'm seeing now. And I can not explain the discrepency without involving tipping the Earth beyond normal limits and literally changing the North/South pole locations.
Even in my madness I can't imagine this happening without someone else noticing.

So why does the Sun now rise almost 30* North of where it has for the past two decades?

Or am I completely wrong and nobody else can see this?

I can only assume Halb will know why things have changed.

im quite sure you're right. though i havent been alive long, i have noticed drastic changes in the seasons and weather. it's never consistant anymore. the timing of the earth has been thrown off.

I'm pretty sure other people with PH.D's and Doctorates would have noticed this type of thing by now.

So the pyrate needs to lay off the RUM :D

Have you done much research? Maybe this is somewhat common knowledge in the scientific community, and nothing really new, so its not in the publics eye.

The azimuthal location of the sunrise can vary quite a bit throughout the year, depending on where you live. You're at about 45 degrees north latitude. Believe it or not, at that latitude you can expect a 55 degree swing in sunrise location over the course of the year, from about 67 degrees east of north on the summer solstice to about 122 degrees east of north on the winter solstice.

Here's a bit of an explanation:

http://curious.astro.cornell.edu/que...php?number=186

Here's a calculator where you can enter your latitude, longitude, and give it a date and a time of day, and it will calculate the azimuth and elevation of the sun at that point in time.

http://www.srrb.noaa.gov/highlights/sunrise/azel.html


Constellations appear to slowly move across the sky from night to night. This is because the earth is moving around the sun. At each sunset, the portion of the night sky that is directly overhead differs from the previous sunset by a little less than one degree. So while Orion was on the horizon at sunset during one part of the year, during other parts of the year it will appear directly overhead at sunset or may not be visible at all.

For the past few years, near the summer solstice the sun has appeared to rise through a gap between two mountains in the distance, as viewed from my kitchen window. It's doing the same thing this year. I think you might be noticing things at different times throughout the year, and perhaps mixing them together in some way.

BJJB

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Originally Posted by bjjb99

Here's a calculator where you can enter your latitude, longitude, and give it a date and a time of day, and it will calculate the azimuth and elevation of the sun at that point in time.

http://www.srrb.noaa.gov/highlights/sunrise/azel.html

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I'm going to give that a try.
I'll go out on the beach and mark a compass in the sand and see if I'm actually imagining things. (things that have nothing to do with too much rum, I never hallucinate during a hangover) I could probably get a 30' circle which should get me to less than 2 degrees of error. Then compare that to NOAA.

But I have asked neighbors "Where does the Sun come up?" and they invariably point to the island that has been my benchmark for a quarter-century.
Yet the Sun still rises off my left shoulder when I face the island in the morning and it's only been during this calendar year that this has ever happened.

Please don't think me ignorant of solar or celestial mechanics. I know what "ought" to be and my observations have previously been in accordance to the point that only the severity of deviation brought it to my attention at all. It's only recently that what I'm seeing is not what I would expect to see based on several decades of observation.

Simple test, if you can take a long exposure photograph at night...

Put a camera on a tripod, aim it at Polaris, and take a long exposure photo. If Polaris traces a small diameter arc in the resultant image, then the Earth is just fine.

BJJB

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Originally Posted by bjjb99

Simple test, if you can take a long exposure photograph at night...

Put a camera on a tripod, aim it at Polaris, and take a long exposure photo. If Polaris traces a small diameter arc in the resultant image, then the Earth is just fine.

BJJB

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Polaris has not always been the "North" star. There's this little thing called "pressesion" which concerns the axial rotation of the poles.
It's part of the reason the solar calendar (equinox to equinox) does not line up with the celestial calendar (fixed star to fixed star).
That 6 hour difference each 12 months (approximately) is why we add one day every four years. But it's not quite 6 hours, Mathematically it works out that to account for those few minutes per year you skip any leap year that ends in double zero and is divisible by four. So the year 2000 was not supposed to be a leap year even though it was included in every calendar printed.

I didn't invent this. The math was worked out by Pope Innocent the First back in the year 1154.

Using Polaris as a fixed point doesn't really help in this situation unless I could compare the arc trace on a long term exposure to one taken previously under similar conditions.
Since I'm not capable of doing that, I'm going to have to rely on attempting to trace the Sun path as far as I am able.
We are less than one week from the furthest point (the Solar Equinox) and already the sunrise has retreated to the hills behind me, and sunset is in the hills behind me.
This is just wrong. I should expect a little over 180* ~ not 250*...
From what I'm seeing, my location is somewhere North of the polar circle but the maps say I'm not.

(sigh) Dementia is often fun, but sometimes confusing. I blame it on the school system for making me learn spherical trig as a child.

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Originally Posted by Pyrate Jim

Polaris has not always been the "North" star. There's this little thing called "pressesion" which concerns the axial rotation of the poles.

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Axial precession of the earth has a period of about 26,000 years. That's far too slow to account for what you've described -- namely, a significant shift in the observed sunrise/sunset points within the past year or so, after about 23 years of no observed changes.

Precession of the ecliptic for the earth has a period of about 70,000 years. That's even slower and also cannot account for what you've described.

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Originally Posted by Pyrite Jim

It's part of the reason the solar calendar (equinox to equinox) does not line up with the celestial calendar (fixed star to fixed star).
That 6 hour difference each 12 months (approximately) is why we add one day every four years. But it's not quite 6 hours, Mathematically it works out that to account for those few minutes per year you skip any leap year that ends in double zero and is divisible by four. So the year 2000 was not supposed to be a leap year even though it was included in every calendar printed.

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All the calendar adjustments you describe are not to compensate for precession. Rather they are the result of the earth's rotation and revolution not being a simple integer ratio of each other. There are 365.25 (and some change) rotations for every one revolution. The calendar corrections are put in place to maintain synchronicity between a calendar year and a seasonal year. The 26,000 year long cycle of where the north celestial pole is pointing has very little impact on this set of computations.

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Originally Posted by Pyrite Jim

Using Polaris as a fixed point doesn't really help in this situation unless I could compare the arc trace on a long term exposure to one taken previously under similar conditions.

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Just about any of the web-based astronomy sites can show you an image of the night sky, from your position on the earth, and often at any particular date and time you wish. You can use that to measure how far Polaris is supposed to be from the earth's north celestial pole. You can compare that with a single measurement made by you. No prior photo is required.

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Originally Posted by Pyrite Jim

Since I'm not capable of doing that, I'm going to have to rely on attempting to trace the Sun path as far as I am able.
We are less than one week from the furthest point (the Solar Equinox) and already the sunrise has retreated to the hills behind me, and sunset is in the hills behind me.
This is just wrong. I should expect a little over 180* ~ not 250*...

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I ran a quick computation for 45 degrees north latitude on the summer solstice (June 21). The sunrise should occur about 58 degrees east of north. Sunset should occur about 302 degrees east of north. That's slightly more than a 240 degree swing, and it's exactly what one should expect at that latitude this time of year.

Check out the following URL:

http://en.wikipedia.org/wiki/Solstice

Look particularly at the diagrams labeled "Day arcs at XX* latitude". For the 50* latitude diagram, look at the summer solstice arc. Draw lines from the sunrise and sunset points to the observer, and eyeball-measure the external angle between them. You'll see that it's noticeably larger than 180 degrees -- it's closer to 270 degrees.

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Originally Posted by Pyrite Jim

From what I'm seeing, my location is somewhere North of the polar circle but the maps say I'm not.

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If you're seeing somewhere around 250 degrees between sunrise and sunset locations, then you're somewhere around a latitude of 45 degrees, which should be in agreement with where maps place you.

I ran another calculation for someone sitting on the north polar circle for June 19, the date you made your most recent post. On that day, someone sitting on the north polar circle would have measured almost 290 degrees between rise and set points. That's significantly greater than what you've measured, so you must be south of that latitude.


Hope this helps,

BJJB

Funny thing, I recently ran across a youtube video that reinforces my opinion.
It was taken about the same time I originally started this thread, in fact it was posted some two days prior (I was unaware of it at the time)
http://www.youtube.com/watch?v=z1yiH...yer_detailpage

But at least it means to me that I ain't the only one noticing weird stuff going on.
I've been living on this lake for 24 years now and this was my grandparents home, I spent a lot of time out here as a kid. Back then we would get a good three months of playing on the ice when the lake froze over. Even when I bought it back in '90 I would see generally six to eight weeks that you could walk on it.
This year I've had two days.


But the sun is now rising about where it should be if we were about five weeks off the Summer Solstice, based on my island landmark and how far left or right of that the Sun is rising.
I've been watching that, and I'm convinced it did not go as far South as it should have at the Winter Solstice although I'm skeptical that my memory is correct about that. I know how far it went this past year (because I was watching) but whether that is far distant from the norm by my observations may be subject to wishful thinking.

It's when it's waaay outside that norm of my observation, then I sit up and take notice.
Sometimes I even ask about it online.

<edit to add>
Found another vid from the same time period, after my original post...
http://www.youtube.com/watch?v=L0SAl...yer_detailpage
Found a third, posted five days later but shows sunset instead of sunrise:
http://www.youtube.com/watch?v=X2CHP...yer_detailpage

I posted on the 3rd, they both posted the same observation on the 11th & 12th.
That's four independent reports.
Now I know I'm not crazy...

Fooling around with a globe of the Earth.
Near as I can tell, to account for the Suns transit that I am measuring the North Pole is somewhere around 105 East and at almost 60 North.
That would put it somewhere North of Mongolia, coincidently very near the Tunguska Range of mountains.

I've always been taught the Earth is 23.5 degrees off vertical relative to the Sun.
According to USGS maps I'm about 41.5 North.

There is no way the Sun should ever hit a true East-West from my location, it should always be South of me even at it's furthest tilt. (meaning Summer Solstice in the Northern Hemisphere). From this latitude I should never be able to plot any Sunrise/Sunset exceeding 180 degrees or even close to that.

What I have been measuring recently is pretty close to true East-West, which would make sense if I were in the Florida Keys this time of year.
It does not make sense when you're removed from that by several thousands of miles.

Anybody can check this for themselves...
All you need is a compass and to get out to watch where the Sun sets & rises.

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Originally Posted by Pyrate Jim

Funny thing, I recently ran across a youtube video that reinforces my opinion.
It was taken about the same time I originally started this thread, in fact it was posted some two days prior (I was unaware of it at the time)
http://www.youtube.com/watch?v=z1yiH...yer_detailpage

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The sun appears to be setting in the northwest. Which is perfectly consistent given the time of year and the apparent latitude of the video's poster. It's simply proof that the poster of the video doesn't understand what he's observing.

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Originally Posted by Pyrate Jim

I've been watching that, and I'm convinced it did not go as far South as it should have at the Winter Solstice although I'm skeptical that my memory is correct about that. I know how far it went this past year (because I was watching) but whether that is far distant from the norm by my observations may be subject to wishful thinking.

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Couldn't have said it better myself. Unless you've gone through the effort to record measurements on a regular basis from the same location(s) at sunrise and sunset over the course of at least a couple of years, you're naturally going to question your own memory.

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Originally Posted by Pyrate Jim

Found another vid from the same time period, after my original post...
http://www.youtube.com/watch?v=L0SAl...yer_detailpage
Found a third, posted five days later but shows sunset instead of sunrise:
http://www.youtube.com/watch?v=X2CHP...yer_detailpage

I posted on the 3rd, they both posted the same observation on the 11th & 12th.
That's four independent reports.
Now I know I'm not crazy...

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The first video of these two -- It's fairly clear that the poster does not know how to use a compass properly, as evidenced by the fact that he's attempting to read a compass direction while standing very close to a steel fence. Large ferrous objects do all sorts of mischief to the magnetic fields in their vicinity.

The second video of these two -- Again he's got his compass on top of a metal railing which, if ferrous, will affect his readings. However, I think this railing may well be aluminum rather than steel. Assuming that, he is noting the sun setting in the northwest, which again is consistent with the time of year and the apparent latitude of the observer.

So you've got two of the three videos showing observations that are consistent with predictions, and one video where the measurement is screwed up due to a large ferrous metal source in the vicinity.

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Originally Posted by Pyrate Jim

Fooling around with a globe of the Earth.

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Since you've got a globe handy, do the following... you'll need the globe and a pencil or some other erasable marking device. You might need a stand or a friend to help hold the globe while you do this:

1. Mark a spot on your globe near where you live. You don't need to be too precise, though try to get the latitude close. The middle of Connecticut should be sufficient.

2. Take the globe outside sometime during the day.

3. Things get a bit tricky from here on out... hold the globe so that the equatorial plane is in line with the sun (i.e. the polar axis is at right angles to the sun's direction).

4. Now, tilt the globe's north pole about 23 degrees towards the sun (this would now simulate summer in the northern hemisphere).

5. Next, rotate the globe about its north/south axis so that the point you marked in the middle of Connecticut is halfway between facing directly toward and directly away from the sun (this would simulate either sunrise or sunset)

6. Holding the globe in this position, draw a short line from the point you marked on the globe towards the sun.

7. Now rotate the globe about its north/south axis so that the center of Connecticut is directly opposite where it was just located (this would now be sunset or sunrise, respectively), and mark another line pointing toward the sun.

8. Take the globe inside and measure the angle on the globe between those two line segments. Also, note whether those line segments point more northward or southward. I'll bet you if you followed these confusing directions correctly those two lines would point roughly northeast and northwest on the globe, and the exterior angle for these to lines would be about 250-260 degrees.

9. Repeat the process, but this time tilt the north pole about 23 degrees away from the sun to simulate winter.


BJJB

My nom de guerre comes from the fact that I do a lot of historical portrayal of a 17th century seafarer. (specifically as an honest merchantman gone "on the account" and living the life of a pirate)
Like civil war re-enacting only based on shipboard.

I mention this because the Captain of our crew has a sextant.
I've just recently asked him to take noon readings, but he has yet to get back to me with numbers. I asked him specifically for a reading at noon on the Equinox although I expect it to be the Summer Solstice that shows the greatest deviation so far.
Why I didn't think of this 7 months ago is just my own stupidity working against me. I should know from simple navigation that it takes three readings (dawn, noon & sunset) to accurately triangulate position on a globe relative to a fixed daystar.
Without those numbers, I'm just talking out my backside when it comes to proof.

Meh. What do I know. I'm the ships carpenter, not the friggin Navigator.
But I know enough to keep a compass away from ferrous metals...
The Compass I use is set in brass on gimballs mounted in a mahogany box and larger than most, my back up is your typical "boy-scout" type set in a rectangular clear acrylic.

But here's the thing that gets me.
If the Earths tilt is supposed to be about 23-1/2 degrees then the sun should always be South of 41 degrees North Latitude. Sun Rise & Sun Set should NEVER be in the NORTH of direct East/West.
If the Sun ever hit perpendicular at noon, I'd be real concerned.

And I really don't have to take a globe outside as long as I have the numbers.
I can do that in my kitchen putting the globe on the counter and using a laser transit on a tripod across the room to simulate the Sun.

I'm just seeing weird stuff going on in the sky. Things that are probably perfectly natural and any discrepency is just my personal paranoia.
However...
The Sun used to rise directly in the front window, I had to arrange the furniture to accomodate this fact for over two decades. Now it's been coming in to the left of that window and hitting the right-hand wall instead of the back wall where it has been for the past 24 years.
I've read up about "pole shift" which deals with where a compass might show Magnetic North to be different from Polar North, but if it's only the compass readings that are screwy then why has the Sun moved relative to the house itself?
For the first time in a quarter-century I've had to re-arrange the furniture just to deal with the Sun rising.
That's just wrong.
Or I am, which is not outside the realm of possibility and I'm fully willing to admit this. I've been wrong before (so many times) but never when it deals with empiric evidence.

Of the two (ontological vs. epistimilogical), I'd rather be the one who is wrong about all this.
There's a good chance I'm "Crying Wolf" for no reason.

But I don't think so.
At least I hope so.

Sometimes I feel like I'm stuck in a bad Star Trek joke:
http://www.vexxarr.com/Vexxarr112111.gif

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Originally Posted by Pyrate Jim

I mention this because the Captain of our crew has a sextant.

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You don't need to wait for an equinox or a solstice.

If it's dark enough where you are at night and your Captain has good enough eyes, have him compute your latitude using Polaris. If the polar axis has shifted as much as you think it has, then he'll get something far removed from 41.5 degrees north. I suspect he's going to come back with nothing out of the ordinary.

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Originally Posted by Pyrate Jim

But here's the thing that gets me.
If the Earths tilt is supposed to be about 23-1/2 degrees then the sun should always be South of 41 degrees North Latitude. Sun Rise & Sun Set should NEVER be in the NORTH of direct East/West.
If the Sun ever hit perpendicular at noon, I'd be real concerned.

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I agree, the sun's position _at_local_solar_noon_ should always be towards the south if you're standing at 41 degrees north latitude. However, this is absolutely not the case at other times of the day. The further north you travel, the further north of direct east/west the sun generally appears at sunrise/sunset. As an example, at local midnight on June 22, 2012 the position of the sun in the sky over Murmansk is above the horizon and _due_north_!

Leap day! :cheers:
Little off topic here, but still celestial mechanics.

We add a day every four years to the Gregorian Calendar to compensate for the discrepency between the Solar Year (Equinox to Equinox) and the Siderial year (fixed star to fixed star).
But it ain't quite six hours every year, is it?

Pope Innocent the First worked out back in the tenth century that those few minutes short each year would add up to a full day about once every 400 years. He proposed skipping any leap year that ended in double-zeros and was divisible by four.
By that reasoning, the year 2000 should not have been a leap year.

I read somewhere that the Julian Calendar (popular before the adoption of the Gregorian and still listed in the Old Farmers Almanac) ~ They saved up all those leap-days until they simply dropped an entire year...

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Originally Posted by Pyrate Jim

Fooling around with a globe of the Earth.
Near as I can tell, to account for the Suns transit that I am measuring the North Pole is somewhere around 105 East and at almost 60 North.
That would put it somewhere North of Mongolia, coincidently very near the Tunguska Range of mountains..

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http://www.youtube.com/watch?v=-l0SC...yer_detailpage

That was posted back in '09, and it's a mere projection. It has nothing to do with the truth as we know it.
The funny thing about this particular CGI is that if you look at it, the North Pole "just happens" to be placed somewhere in the same region of Russia that I posted...

Another coincidence?

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Originally Posted by Pyrate Jim

http://www.youtube.com/watch?v=-l0SC...yer_detailpage

That was posted back in '09, and it's a mere projection. It has nothing to do with the truth as we know it.
The funny thing about this particular CGI is that if you look at it, the North Pole "just happens" to be placed somewhere in the same region of Russia that I posted...

Another coincidence?

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A video posted by an organization dedicated to preparing for "economic depression, world war III, food & water shortage, martial law, exponential conscious evolution, earth changes, geophysical and magnetic pole shift, passing galactic equator, and entering a new ice age."?

I think "nothing to do with the truth" is a far more accurate assessment than "another concidence?". I'd also have to say that I think the organization's founder, Ivan Stein, is a nut.

Back to the measurement at hand... let us know when your Captain has made his sextant measurements. The spring equinox is less than a week away. I'll go ahead and make a prediction that he will find the sun's elevation above the horizon at noon on March 20 to be nearly 49 degrees, give or take a couple of degrees to account for any error in his measurements.

Turns out me Cap'n can be left out...

But I did a little bit of simple geometry by putting a level board with a rod of known height and measuring the length of the shadow.
At 1:15 PM the shadow reached it's minimum distance to the rod.
That gave an angle of about 41 degrees. Which is as it should be.

I tried to mark the board with a North/South orientation, but I'm not sure about my measurement of the magnetic pole being correct. I know from boy scouts that the two are not perfecly in alignment (even the compass is marked showing the deviation), but the shadow was pretty far off from even that. It crossed that line before noon prior to reaching zenith.

Although lately I've been watching the evening sky where the sun sets and noticed something odd.
I can see Venus and another, much brighter light.
Mars is ascending behind me, Jupiter is not in the sky at night and I haven't seen the moon since the just after the full moon of February.
That's when I first noticed the bright companion to Venus.
Both mars & venus are going along in their orbits which for me is up & down the sky as we rotate beneath, this bright point has been moving basically sideways. First is was below Venus, then about even and now going above it. And it's moving fast compared to the other visible planets.
Go look at it, and watch it for a few days.

The brighter and faster-moving of those two lights is actually Venus (magnitude -4.5 -- really, really bright). The dimmer of the two is Jupiter (magnitude -2.1 -- still very bright). They're the two brightest objects in the night sky after the moon.

Jupiter is in the sky at night during March of this year, though it's getting lower and lower in the sky each night. The recent proximity of Jupiter and Venus has been a particularly pleasant evening sight. If the sky had been clear the last couple of nights, I would have been able to see a thin crescent moon joining the show... but alas, clouds have foiled my view. Tonight is looking like it might be clear, though. The crescent moon should be above and to the left of Venus.

http://www.skyandtelescope.com/observing/ataglance