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nebularain
2010-Mar-02, 12:56 AM
HI, I haven't been on in ages, if anyone is still here who remembers me.

Anyway, I happened to see the Moon rising, as it was just above the horizon. It was a bright red ball! (7:40-ish Eastern time)

????

It began losing its redness as it rose higher.

But what could have made it so bright red along the horizon tonight?

grant hutchison
2010-Mar-02, 01:51 AM
Same thing as makes sunrises and sunsets red: short-wavelength light being efficiently scattered by the extra thickness of atmosphere along the line of sight towards the horizon. You can see the same effect with bright planets and stars, like Venus and Sirius.

Grant Hutchison

nebularain
2010-Mar-02, 02:22 AM
Sure - I've just never seen it THAT red before!

It was even more red than the last lunar eclipse I managed to see.

I was wondering if there was something east of here (central MD) that could have left a huge amount of dust in the atmosphere or something?

mantiss
2010-Mar-02, 03:02 AM
Smog would do that, especially if it's trapped with a temp. inversion layer. Were you looking through an urban setting?

Middenrat
2010-Mar-02, 03:03 AM
I noticed the moon setting this morning, neatly opposite the sunrise as befits a full phase, and it was dusky pink going coppery.
Could it be that our satellite was close to being in eclipse and was receiving a larger than normal portion of atmosphere-filtered sunlight on this orbit?
Whatever, it was strikingly beautiful.

nebularain
2010-Mar-02, 02:48 PM
Smog would do that, especially if it's trapped with a temp. inversion layer. Were you looking through an urban setting?

No, suburban. I'm smack in the middle of the corridor between Baltimore and DC.

I'm used to seeing a reddish tint to the Moon near the horizon.

Golly, I wish someone else had seen it.

It was really did look something like this: http://lpod.wikispaces.com/file/view/LPOD-Apr19-09.jpg/68400009/LPOD-Apr19-09.jpg! That's why it startled me.

grant hutchison
2010-Mar-02, 04:27 PM
I noticed the moon setting this morning, neatly opposite the sunrise as befits a full phase, and it was dusky pink going coppery.
Could it be that our satellite was close to being in eclipse and was receiving a larger than normal portion of atmosphere-filtered sunlight on this orbit?We can't blame a flirtation with Earth's shadow. The moon was more than four degrees south of the ecliptic during the most recent rotation of the Earth. The Earth's (umbral) shadow sits on the ecliptic and is only 1.4 degrees across.

Grant Hutchison

George
2010-Mar-03, 01:01 AM
Sure - I've just never seen it THAT red before!

It was even more red than the last lunar eclipse I managed to see.

I was wondering if there was something east of here (central MD) that could have left a huge amount of dust in the atmosphere or something?
How stormy were the winds in your region? The dust and particulate levels increase during the day due to convection, so a strong wind blowing eastward of your position likely increased the scattering particle levels enough to allow for a red Moon.

Are you sure it wasn't orangish red? [True red is rare.]

nebularain
2010-Mar-03, 01:10 AM
It was red enough that I first thought it was some club's project to have an orb covered in red lights set on top of the parking garage. As I walked closer, it was then I discovered it was the Moon. It didn't start looking orangy until after it rose higher.

Tobin Dax
2010-Mar-03, 01:22 AM
Well, hi there, stranger. It's good to see you around, nebularain.

George
2010-Mar-03, 02:27 AM
It was red enough that I first thought it was some club's project to have an orb covered in red lights set on top of the parking garage. As I walked closer, it was then I discovered it was the Moon. It didn't start looking orangy until after it rose higher. Ok, some see red differently than others, I've learned.

What about the winds? Hasn't been stormy lately?

David Mc
2010-Mar-03, 07:02 PM
The only infrequent occurrences I can think of are the Peru earthquake and the snow storm.

A gas release from the earthquake, atmospheric conditions from the storm, power outages prompted more fireplaces being lit.

I'll take the reverse of that order.
1 pollution
2 atmospheric effect
3 rare seismic event

nebularain
2010-Mar-04, 06:01 PM
Well, hi there, stranger. It's good to see you around, nebularain.

Hi!!

nebularain
2010-Mar-04, 06:05 PM
The only infrequent occurrences I can think of are the Peru earthquake and the snow storm.

A gas release from the earthquake, atmospheric conditions from the storm, power outages prompted more fireplaces being lit.

I'll take the reverse of that order.
1 pollution
2 atmospheric effect
3 rare seismic event

Well, that would be weird, but it's as good a guess as any I suppose.


George - it was between storms. But I didn't notice any clouds in the eastward direction.

chrlzs
2010-Mar-04, 09:01 PM
Bit late now, but next time, if a decent camera (long zoom would be good..) is around...

Tripod preferable but not mandatory - lean camera against something.
Set zoom to longest (but not 'digital' zoom) and manual focus on infinity.
Spot meter or manual exposure ~ 1/125, f5.6 (ISO100, and assuming it's still pretty bright) and bracket if possible, ie take other shots above and below those settings. It will look dim in the viewfinder, but if you use a nighttime exposure you will probably blow it out..
Manual white balance - set to 'daylight', otherwise the camera will try to compensate for the color.

Also, you could try ringing your local weather bureau or news services, or astronomy club at the time. With today's indoor society, the people that matter in your area might all be inside, and miss the spectacle.

Smog/pollution, or a fire or dust storm would be the most likely culprit.

Graybeard6
2010-Mar-05, 12:10 AM
I saw the same thing Sunday evening on the east coast of Florida. We were driving east from the mainland toward the ocean, and it was so clear that there was a light path on the water. That eliminates any local phenomenon.
I must start carrying a camera in my car more.

chrlzs
2010-Mar-05, 07:04 AM
I saw the same thing Sunday evening on the east coast of Florida. We were driving east from the mainland toward the ocean, and it was so clear that there was a light path on the water. That eliminates any local phenomenon.
I must start carrying a camera in my car more.

I'm not sure I get it - what do you mean by a 'light path on the water'?

grant hutchison
2010-Mar-05, 11:17 AM
I'm not sure I get it - what do you mean by a 'light path on the water'?From context, I think Greybeard6 is talking about a moonglade: the apparent bright path across the water between the observer and the moon, which is created by many partial reflections of the moon from the sloping surfaces of many small waves.

However, I'm not sure how that would eliminate any local phenomenon: it's likely that the moonlight is being reddened by an atmospheric filter before it is reflected by the water; but it's also possible that moonlight and moonglade are both being reddened by some more local filter much closer to the observer: a cloud of smoke rising between the observer and the water, for instance.

Grant Hutchison

chrlzs
2010-Mar-05, 11:49 AM
From context, I think Greybeard6 is talking about a moonglade: the apparent bright path across the water between the observer and the moon, which is created by many partial reflections of the moon from the sloping surfaces of many small waves.

However, I'm not sure how that would eliminate any local phenomenon: it's likely that the moonlight is being reddened by an atmospheric filter before it is reflected by the water; but it's also possible that moonlight and moonglade are both being reddened by some more local filter much closer to the observer: a cloud of smoke rising between the observer and the water, for instance.

Grant Hutchison

You pretty much made my point - the ocean reflection doesn't really tell you anything, unless it was a different colour - then I'd have to think about it..! I thought maybe there was a special meaning of the term 'light path' that meant something else.

dls5000
2010-Jul-29, 01:15 PM
I saw it too it was kind of creepy

trinitree88
2010-Jul-31, 04:29 PM
nebularain. With regards to your red moon..Ahem. The moon is normally made of green cheese, but was suffering a short-lived invasion of red fungi...SEE:http://www.forumgarden.com/forums/attachments/test-forum/28991d1253481552-can-i-edit-blinking-title-blimey-i-think-i-can-moon.jpg
SEE:http://img1.eyefetch.com/Portfolio%5Cmadhatter%5C55762.jpg Ahem. Pete

George
2010-Aug-01, 07:35 PM
nebularain. With regards to your red moon..Ahem. The moon is normally made of green cheese, but was suffering a short-lived invasion of red fungi...SEE:http://www.forumgarden.com/forums/attachments/test-forum/28991d1253481552-can-i-edit-blinking-title-blimey-i-think-i-can-moon.jpg
SEE:http://img1.eyefetch.com/Portfolio%5Cmadhatter%5C55762.jpg Ahem. Pete Psychologists have a behavioral term related to this. :)

trinitree88
2010-Aug-02, 04:39 PM
Psychologists have a behavioral term related to this. :)

George. Yep...it's called lightening up the board. Sometimes when the moon is visible during class time, I take my laser pointer, explain to the students how the lunar ranging mirrors work, and give some gullible student a stopwatch. We'll use the average lunar orbital radius, and get the speed of light....OK? Then have them wait a few seconds for a return pulse. One always needs to check to see if student brains actually have a pulse.....and true to form some kid will burst out laughing on the unliklihood of getting a result. But you always have to remember Project MOHO...that began as a joke. :shifty::clap::lol: pete

George
2010-Aug-02, 07:25 PM
George. Yep...it's called lightening up the board. Yes, but I failed to mention that a pun was the basis. I think "lunacy" is the term for the behavior you describe. :)


Sometimes when the moon is visible during class time, I take my laser pointer, explain to the students how the lunar ranging mirrors work, and give some gullible student a stopwatch. We'll use the average lunar orbital radius, and get the speed of light....OK? Then have them wait a few seconds for a return pulse. One always needs to check to see if student brains actually have a pulse.....and true to form some kid will burst out laughing on the unliklihood of getting a result. That's a good one! There's always a little incoherence with coherence; anisotropy with isotropy; etc. :)

One of our club members loves to put on astronomy Power Point presentations and he when he comes to something such as a montage of the planets of the Solar system, he will point to Jupiter and ask the kids "What is this". They say Jupiter, he says, "No, it's just a red dot!".

Tobin Dax
2010-Aug-03, 11:39 PM
George. Yep...it's called lightening up the board. Sometimes when the moon is visible during class time, I take my laser pointer, explain to the students how the lunar ranging mirrors work, and give some gullible student a stopwatch. We'll use the average lunar orbital radius, and get the speed of light....OK? Then have them wait a few seconds for a return pulse. One always needs to check to see if student brains actually have a pulse.....and true to form some kid will burst out laughing on the unliklihood of getting a result. But you always have to remember Project MOHO...that began as a joke. :shifty::clap::lol: pete

:shifty: Makes mental note. Thanks, Pete. :)
This could actually be a fun, "spontaneous" thing to due during my nighttime observing session or my night class later in the semester. I just have to remember the stopwatch, though someone's phone should have one.

Glom
2010-Aug-04, 08:58 AM
Welcome back, neb. The only explanation I can see is that you were in fact on Mars, which must therefore mean you are also Dr. Manhattan.

Although, it was probably just a bit dusty.

Sticks
2010-Aug-04, 10:55 AM
It wasn't a Lunar eclipse by any chance?

Tobin Dax
2010-Aug-04, 05:07 PM
Welcome back, neb. The only explanation I can see is that you were in fact on Mars, which must therefore mean you are also Dr. Manhattan.

Although, it was probably just a bit dusty.

In case you missed it, Glom, the OP was made about 5 months ago. nebularain hasn't signed in since a few days after his post.

Glom
2010-Aug-04, 07:04 PM
neb is a girl, isn't she?

George
2010-Aug-04, 09:16 PM
It wasn't a Lunar eclipse by any chance? The Moon can also appear purplish in some Lunar eclipse cases. Volcanic activity in our atmosphere can scatter light so that red and blue are more dominant than the other colors. [There's an old thread about this with eburacum45(?), who saw one.]

Tobin Dax
2010-Aug-05, 01:13 AM
neb is a girl, isn't she?

I honestly don't remember anymore. I apologize if I was mistaken.

JustInterestedInSpace
2010-Aug-05, 12:25 PM
It is most probably the same thing making the Sunsets in the UK red during march, you may remember the Volcano that erupted causing flight chaos, My astronomy teacher said that the ash and dust was distorting the light when it was on a shallow angle to earth, for example the Moon being low in the sky.

This explains why it lost the redness as it was higher in the sky.