Interesting accidental observation last night


jimcoble2000
 

After being totally skunked out by poor weather last night I arrived home to see that the southeast sky had cleared a bit around 1045. I hurriedly set up the 4 inch to get a quick look at the moon and Jupiter. Upon arriving at the moon I noticed something unusual. The face was totally lit. Now before you think this is a statement of the obvious, full moon was last night, consider this.

We usually think of full moon as a day in which the face is lit but that is really not accurate. As the terminator is constantly on the move across the face of the moon, most times we see some contrast between the lit and unlit side. It may be thin but it is always there..........except when you observe it at exactly the moment when the moon is full. That is actually a very short time, perhaps not much more than an hour, maybe less. What caught my eye was that there was absolutely no contrast to be had on the moon anywhere. In all the years I have observed it I have never looked at exactly the right time.It was obvious and pure luck. Roy informed me the moon was officially full at 2230 last night. In a few hours it would be heading for third quarter and a razor thin terminator would start to work it's way across the face. That was an accidental interesting observation that demonstrated that a lot of what we assume temporally is really not correct and that change is constant even on the moon.


Roy Diffrient
 

Actually you were even closer, Mark – the 100% full moon occurred at 10:37:03 PM on Friday, July 23, 2021 at Virginia Beach.  Not that anyone could tell the difference.

Roy


On Jul 24, 2021, at 9:16 PM, jimcoble2000 via groups.io <jimcoble2000@...> wrote:


After being totally skunked out by poor weather last night I arrived home to see that the southeast sky had cleared a bit around 1045. I hurriedly set up the 4 inch to get a quick look at the moon and Jupiter. Upon arriving at the moon I noticed something unusual. The face was totally lit. Now before you think this is a statement of the obvious, full moon was last night, consider this.

We usually think of full moon as a day in which the face is lit but that is really not accurate. As the terminator is constantly on the move across the face of the moon, most times we see some contrast between the lit and unlit side. It may be thin but it is always there..........except when you observe it at exactly the moment when the moon is full. That is actually a very short time, perhaps not much more than an hour, maybe less. What caught my eye was that there was absolutely no contrast to be had on the moon anywhere. In all the years I have observed it I have never looked at exactly the right time.It was obvious and pure luck. Roy informed me the moon was officially full at 2230 last night. In a few hours it would be heading for third quarter and a razor thin terminator would start to work it's way across the face. That was an accidental interesting observation that demonstrated that a lot of what we assume temporally is really not correct and that change is constant even on the moon.


jimcoble2000
 

No difference there by minutes

On Saturday, July 24, 2021, 11:01:11 PM EDT, Roy Diffrient <mail@...> wrote:


Actually you were even closer, Mark – the 100% full moon occurred at 10:37:03 PM on Friday, July 23, 2021 at Virginia Beach.  Not that anyone could tell the difference.

Roy


On Jul 24, 2021, at 9:16 PM, jimcoble2000 via groups.io <jimcoble2000@...> wrote:


After being totally skunked out by poor weather last night I arrived home to see that the southeast sky had cleared a bit around 1045. I hurriedly set up the 4 inch to get a quick look at the moon and Jupiter. Upon arriving at the moon I noticed something unusual. The face was totally lit. Now before you think this is a statement of the obvious, full moon was last night, consider this.

We usually think of full moon as a day in which the face is lit but that is really not accurate. As the terminator is constantly on the move across the face of the moon, most times we see some contrast between the lit and unlit side. It may be thin but it is always there..........except when you observe it at exactly the moment when the moon is full. That is actually a very short time, perhaps not much more than an hour, maybe less. What caught my eye was that there was absolutely no contrast to be had on the moon anywhere. In all the years I have observed it I have never looked at exactly the right time.It was obvious and pure luck. Roy informed me the moon was officially full at 2230 last night. In a few hours it would be heading for third quarter and a razor thin terminator would start to work it's way across the face. That was an accidental interesting observation that demonstrated that a lot of what we assume temporally is really not correct and that change is constant even on the moon.