Your personal experiences of unusual phenomena?

[Janitor]

I am curious to read personal anecdotes any of you may have about physical phenomena that are not seen very often. I don't mean deliberate observations in a laboratory setting. Just something that happened when you were not expecting it. For instance, supposedly the sun as it is setting (or rising?) can sometimes seem to give off a green (?) flash. I have no idea what that is about, or if it is true. I have never seen it happen. Also, pilots speak of something called a "glory" which is kind of a halo that is sometimes seen near clouds. Ball lightning sounds wild and crazy, but it has been observed enough times that it is likely to be for real.

As for me, I can think of two things that happen rarely enough that I have only experienced them once each.

One morning I was stopped behind a cement truck at a red light. It was cold (by desert standards, anyway) and there was no discernable wind, if those are parameters that matter. When the light turned green and the truck driver hit his throttle, a smoke ring came out of the vertical exhaust pipe's open end and rose slowly up into the air. I watched it rise for a good 5 seconds. Other than that, I've only seen smoke rings coming from the mouths of smokers.

One day I wanted to cool a cup of tapwater quickly, so I put it in the freezer. When I took the cup out of the freezer, I noticed it was completely liquid; there was no skin of ice on it. I put it up to my lip to drink it, and the moment the water touched my upper lip I felt a funny sensation and heard a sound coming from the cup. I pulled it away from my mouth, and the cup was full of opaque white slush. I take it this was an example of supercooling, and my lip provided a surface for freezing to start, and the freezing propagated from that point to the rest of the water in the cup over the course of about one second. It probably says something good about whoever had washed the cup.

 

[ZapperZ]

A very good question, Janitor. :)

I can think of two.. and one of them, I have asked my students (when I used to teach intro physics) to actually test.

The first is actually something familiar but only if one pays attention to it. If you heat water in a cup, sometime, depending on how long you heat it, when you take it out and put in a tea bag, for example, it starts to "boil" or foam up. This is true even if the water you took out isn't boiling. There's a simple explanation for this, of course.

The 2nd is more fascinating. I used to ride the Chicago CTA trains and often, you get groups of people or kids getting on it with helium-filled balloons. The fun thing happened when the train started to accelerate. If the balloon isn't rubbing against anything, you start seeing something non-intuitive. Instead of being pushed back as the train gains speed like the rest of us, the balloons actually started tilting FORWARD. The higher the acceleration, the more the balloon tilted forward.

I gave that last one to my students and almost all of them guessed initially that the balloon will tilt backwards as we all naturally expected. They then had the weekend to actually ride the train with helium balloons and tested this out myself. I was told by someone that there were sightings of students riding the CTA trains that weekend with large quantities of helium-filled mylar balloons. :)

This one too has a very simple explanation for it.

Zz.

 

[zoobyshoe]

Here in San Diego there is a wndow rattling sonic boom once or twice every year that no one can account for. The military doesn't allow any supersonic flight that might cause this over a populated area, and they also routinly deny any munitions testing or accidents that could account for these booms.

I happened to read about this phenomenon in a book called Mysteries of the Unexplained and discovered that it has been reported all over the world dating back even before the invention of explosives. My guess is that they are meteorites that are hitting the atmosphere at a sharp enough angle that they heat to explosion almost imediately, rather than undergoing a slow burn.

 

[pmb_phy]

Cool topic. I have several examples that I can think of.

When I was a kid we had a small closet in the wall in the kitchen which was filled with cookies and sweets and stuff. Obviously my favorite closet in the house. One night only my brother and myself were in the kitchen and I was looking in the closet to decide what I wanted. My brother was off to the left of me sitting at the table reading. As I was gazing into the closet I felt a hand press on my back and I spun around to tell my brother to wait until I was finished only to see him still sitting at the table a few yards away.

Then there was the time a bunch of my pals and I were partying in a graveyard. It was the thing to do back then in my town. It was a beautiful clear night. I was gazing up at the stars and noticed that one of them was green. As I stared at it I noticed that it was getting brighter until it was so bright that everyone was looking up at it and it was able to slightly light up the area we were in. All of a sudden it snapped to a bright red and shot off in another direction so fast that my eye couldn't follow it. We were all stunned. Huh! That was weird hug guys? - Yeah! I need another beer!

I was stationed in Denver Co when I was in the USAF. I got my orders transfering me to Tucson. I grabbed a ride with some other people I knew and we drove there. In doing so we drove through New Mexico. One night we were on a very long road in the middle of nowhere. I was driving. I noticed a "car" up in the distance "comming towards me" and was wondering when this guy would dim his "high beams". But after a while I noticed that he was still off in the distance. I thought it was a very bright light which was stationary but after 15-20 minutes it never moved. So I thought perhaps that it was a car with its tailight "red" plastic removed and it was that white light that I was seeing. So I sped up to a much higher speed (50->80) and remained at that speed and it never got closer. So I thought I was imagining it so I woke up my friend and he said "Oh. That's just a car!" and as we waited he realized it wasn't a car. We woke up the other guy and he said "Oh. That's just a car!" and as we waited he realized it wasn't a car. Funny thing - I don't recall whatever happened to that light. I just recall the rest of the trip.

Then there was the time I was sitting in my living room about the year before last. I was watching the TV with the lights off. I hears a snap and a bright blue light in my bedroom. I thought it was my friend who came in that door and was being a wiseass. But when he never came into the livingroom I went into the bedroom - nobody there. I checked the door - locked. I went back into the living room thinking "Huh! That's weird." And as I was watching TV it happened again and this time I rushed into the room and turned on the lights. Nobody there. I quickly went and smelled the electrical outlets for the sent of ozone and then quickly looked out the window to see nothing.

 

[mhernan]

Relativity -slipping out of place?

When I was a child, before first grade I was eagerly awaitng Santa Claus to come and go so I could get my "stuff". I heard a tingling bell and then my grand father calling out to n me to "hurry or I would miss seeing Santa Claus". I burst to the front of the house with grandpa urging me to hurry. Well, I tell you, I saw the sleigh and the reindeer as they climbed over a house about one block away.
I tell you:I saw Santa Claus and I saw him as clear as the sky.

But I still can't accept relativity, nor quantum theory, but this is because these models are mere mathematical arifacts, both of which Mother Nature has yet to inform me to the contrary.

 

[Janitor]

I am loving it, guys.

 

[chroot]

Let's keep these accouns strictly "physically explainable," guys, or it'll have to go to the Skepticism and Debunking forum.

- Warren

 

[Janitor]

Zoobyshoe's story reminds me--

There were no supersonic aircraft in 1805. Lewis and Clark were making their way along the Missouri River, along with their band of explorers. They reported in their journals that there was a loud boom that they could not attribute to a waterfall or buffalo herd or Indian activity. Nobody really knows today what it might have been, but a meteorite is a possibility, I would say.

As a kid I started noticing that on a sunny day, as my shadow approached the shadow cast on the ground by a building eave, the two shadows would appear to bulge out toward one another and "make contact" so to speak. I assume it is some kind of manifestation of the diffraction of light.

EDIT: Deleted smilie face because the recent update in website software turned it into an odd string of ASCII characters.

 

[pmb_phy]

Originally posted by chroot
Let's keep these accouns strictly "physically explainable," guys, or it'll have to go to the Skepticism and Debunking forum.

- Warren

That goes counter to the spirit of science. Janitor was only inquiring into personal experiences. All science start with observation and this topic is regarding physical phenomena that are not seen very often. If the topic was ball llightning would you wish us not to discuss it because it's rarely seen?

In actuality, if I had to bet, then I'd say that what I saw in one case was really ball lighting but I'm reporting only what I saw and not specultating as to what it was. In the first case of the "hand" I'd say it a was a weired "misfiring" of synapses and in the New Mexico case it was probably some bizarre optical phenomena regarding lights of a distant otherwise unseen city that occurs so rarely as to be normally unheard of. But again - that would be speculation - I posted only facts in my post.

 

[zoobyshoe]

I think Chroot was reacting to the Santa Claus story.

 

[Evo]

I witnessed a very unusual ice ring around the moon years ago. It was so strange that it was on the news the next day because so many people had called in about it. There was no explanation from experts.

Instead of being a typical "halo" it was a very defined bright white ring very close to the moon, almost touching it. What was so odd was that the ring was slowly enlarging creating an ever increasing clear area around the moon while retaining a clearly defined "rim" for the outer circle. We continued to observe this for almost 30 minutes until the ring covered most of the sky and started fading.

I've never seen a phenomena exactly like it explained anywhere, I have seen pictures of moon halos, and they are nothing like this ring. So that's kinda cool that I was lucky enough to see it.

 

[Janitor]

I don't know if this falls into the regime of electrochemistry or what, but even on the coldest of mornings my beat up old car starts up within a half second of cranking. When I install new spark plugs, it takes three seconds of cranking for the first start. I am guessing there may be a film of oil or something on the face of the electrodes of the plugs as they come from the factory that causes problems.

 

[Chi Meson]

I've got two:

About a year ago I was heating some diced carrots in the mocrowave for my infant daughter. I heard a sound like a shorting power cable, and I turned to see a fountain of sparks coming out of the carrots. I've since read about this phenomenon and evidently due to the size of the cubes of the carrots, an electric resonance was created. If I let the sparks continue, I could have created a little plasma cloud! There's a nice website about this involving grapes, google it yourselves!

Other thing, last winter saw sun dogs for the first time. But the thing that I never heard anyone talk about was that there were Two distinct rings in the sky: there was the ring around the sun (with the sun at the center); there was also a circular ring around the whole sky, with the zenith at the center and the sun on the perimeter. THe sun dogs were at the intersection fo these two rings. I still can't figure out the optics that would make that second ring. Yes I did get a video of it.

 

[Evo]

Originally posted by Chi Meson
Other thing, last winter saw sun dogs for the first time. But the thing that I never heard anyone talk about was that there were Two distinct rings in the sky: there was the ring around the sun (with the sun at the center); there was also a circular ring around the whole sky, with the zenith at the center and the sun on the perimeter. THe sun dogs were at the intersection fo these two rings. I still can't figure out the optics that would make that second ring. Yes I did get a video of it.

I've never seen a sun dog, but what you saw may be on this site. I would love to see one of these.

http://www.sundog.clara.co.uk/halo/halosim.htm

I have seen a spectacular sun pillar, and could not find a camera in time to take a picture. There are photographs of some on this site. The one I saw was awesome, a solid hot pink pillar shooting staight up.

http://www.photon-echoes.com/pillars.htm

 

[mhernan]

Originally posted by chroot
Let's keep these accouns strictly "physically explainable," guys, or it'll have to go to the Skepticism and Debunking forum.

- Warren

I thought the question was personal experiences. Hey, I was only a kid and was unable to offer any "physically explainable" model.

 

[Chi Meson]

Originally posted by Evo
I've never seen a sun dog, but what you saw may be on this site. I would love to see one of these.

http://www.sundog.clara.co.uk/halo/halosim.htm

I have seen a spectacular sun pillar, and could not find a camera in time to take a picture. There are photographs of some on this site. The one I saw was awesome, a solid hot pink pillar shooting staight up.

http://www.photon-echoes.com/pillars.htm

Great! IT has a name! a Parhelic circle; thanks for the site!

 

[zoobyshoe]

Here's a link to the grape and microwave effect reported by Chi Meson. It is short and fun reading. I can't wait to try it.

Fun with Grapes - A Case Study
Address:http://www.pmichaud.com/grape/

There were other sites, too.

 

[LURCH]

My first time flying an airplane, I saw an entire rainbow. I turned to the west to head back to the airport, and away from the approaching stormclouds, and there was this rainbow that was a complete circle! It looked so solid, it seemed that I could have flown right through the middle.

It was one of those moments of revelation, and in an instant I became aware that all rainbows are fully circular, and we don't see the nottom half because we are standing on the ground, which puts the horizon right across the middle.

It was a sight I'll never forget!

 

[pmb_phy]

I forgot to mention that the green and red lights that we saw may have been a meteorite breaking up in the atmosphere. I.e. when the meteor was comming in it was heading straight towards me and was made of a material which burned bright greem. When it got to a certain point it broke up and turned red and I suspect that when it broke up it was made of a different material inside which started to burn. Probably one part took off in one direction with no light (or we didn't notice it) while the other part turned bright red and shot off the other way.

Is that possible?

 

[Janitor]

pmb_phy

I have heard that booster rockets and satellites that burn up in the atmosphere tend to be brighter, more colorful, and longer lasting than any natural meteor that you are ever likely to witness. I wonder if you were seeing a man-made object?

 

[ZapperZ]

Moral of the story? :)

It's been several days since the last posting on this string, so I'm assuming that we're all done with it. So Janitor, since you started it and asked us to relate our experiences, was there a particular reason other than simply "curiosity" that made you start this? And at the end of all this, was there something you learned other than the fact that there are some very "weird" things going on? :)

BTW, it might be an interesting exercise to start a similar discussion but to include what you excluded in this one - a "strange" or unusual phenomena happening within the research environment. Physicists always get accused of not wanting to go beyond what are in the books, or beyond conventional theories, when in reality, their profession involves studying things that are new, do not have an accepted explanation, or simply violate present-day understanding. Unless I'm mistaken, we have many physicists on here, and it would be fascinating to hear the "new", unusual, and controversial stuff they're working on.

Zz.

 

[gta-maloy]]

I was fortunate enough to witness a form of "dual" lightning, was amazing. Was seen as being both forms, one heading towards the sky and the other heading towards the earth. I haven't seen anything alike since.

 

[Janitor]

Hello ZapperZ

I guess it was simple curiosity that motivated me to start this thread. I learned about an interesting microwave experiment, though I am afraid to try it at my own house.

If any member who has actual 'sperience in a lab wishes to start a similar thread on observations made in a more formal way, I will enjoy reading the responses.

Zoobyshoe's mention of rattling windows just brought something to mind. A few years back I was watching Larry King's show on CNN early one evening. (If I remember, he was interviewing the actress Raquel Welch.) All of a sudden my window rattled as if a little bomb had gone off in the neighbor's yard. In actuality, it was caused by a fatal vehicle collision 80 yards from my house. I noticed that two of the tires on one of the vehicles involved in the crash were blown. I suspect that the bursting tires emitted a shock wave which caused the window rattling at my house.

 

[Janitor]

A challenge

Imagine you have purchased one of the clear plastic bottles of soda, and you have handled it carefully so that it is not going to produce much, if any, foam when you unscrew the cap and let off pressure. What do you think will happen to the level of the top surface of the soda, relative to the printing on the bottle? Will it go up, go down, or stay where it was?

I know the answer from actually observing the "experiment," but I would enjoy hearing predictions from others based on what your intuition or your theories tell you should happen.

 

[motai]

Imagine you have purchased one of the clear plastic bottles of soda, and you have handled it carefully so that it is not going to produce much, if any, foam when you unscrew the cap and let off pressure. What do you think will happen to the level of the top surface of the soda, relative to the printing on the bottle? Will it go up, go down, or stay where it was?

I know the answer from actually observing the "experiment," but I would enjoy hearing predictions from others based on what your intuition or your theories tell you should happen.

From pure intuition I believe that it would rise. Since the CO2 bubbles are gone (no foam that would usually make it very noticeable) the drink would still be at a higher pressure than atmospheric pressure. Therefore, when the drink is opened and the pressure suddenly drops, a rise in volume must occur to offset the difference (albeit extremely small, liquids arnt nearly as compressible as gases).

But since the thread calls for unusual phenomenons, I am thinking that my intuition isn't the best choice.

 

[Janitor]

Thanks Motai

I will wait a day or two before commenting, just in case any other members wish to weigh in on this topic.

 

[turin]

I agree with Motai, but will include the influence of the strain on the plastic being relieved as the primary mechanism. Come to think of it, I'm not so sure that the bottles are not vacuum sealed, or if the pressure at which they are sealed is controled. If the bottles were vacuum sealed at close to room temperature, then I would suspect the liquid level to drop, but under the same basic mechanism.

 

[LURCH]

I also agree with Motai. Those bottles always seem to have positive pressure which is released when the cap is opened. So as Turin mentioned, the plastic is stressed outward (when you grab an unnopened bottle, it feels hard), and when this pressure is released, the fluid level rises, due to the decrease in pressure on the fluid, and the shrinking diameter of the bottle.

BTW, have any of you ever opened a soda bottle at high altitude? I was in the mountains once and unthinkingly opened a bottle of soda whcih appearantly had been bottled at sea-level. You would think they would make provisions for that sort of thing if they're going to call their drink "Mountain Dew"^TM!

 

[Janitor]

Thanks folks for participating.

The answer from actually observing the process is that the liquid level rises. Hopefully no one will dispute that after checking into it on their own!

Feel free to blow me out of the water on my explanation for why the level rises. Here goes...

I can see three things that need to be considered:

1. There is a positive gage pressure in the bottle, and to the extent that a liquid is compressible, that would tend to raise the level of the liquid when the cap is unscrewed, since the liquid is being decompressed.

2. The carbon dioxide under pressure in the unopened bottle is partially absorbed by the liquid. (I say "partially" because obviously there is some ullage at the top of the bottle where there is gaseous carbon dioxide present.) At least some of the carbon dioxide in the liquid phase is converted to carbonic acid. At any rate, whether the absorbed CO2 be acid or dissolved gas, it must take up some room in the liquid, such that unscrewing the cap and releasing the CO2 from the liquid should decrease the volume of liquid and tend to lower the level of the liquid.

3. The shape of a soda bottle is approximately a cylinder. The more pressue they applied to the contents of the bottle at the factory, the more nearly the bottle would have tried to bloat into the shape of a sphere, since a sphere can hold the most volume for a given amount of surface area. In unscrewing the cap and letting the pressure drop, the bottle is allowed to relax back to a narrower, more nearly cylindrical shape which tends to raise the level of the liquid.

Without actually making an effort to look up physical parameters and quantify things, I will speculate that effect (1) is the smallest, effect (2) is intermediate, and effect (3) is the biggest and dominates the other two.

If the bottle were made of glass--something I don't seem to ever see these days so that I can observe what happens with it--I am predicting that effect (3) would become tiny since glass is so highly inelastic, and that effect (2) would dominate. So I am saying that with a glass bottle, the level of liquid would likely drop when unscrewing the cap. Whether it would be enough of a drop to be visible to the naked eye, I don't know. Probably it would not be visible.

 

[KingNothing]

I'm not sure if this is physically explainable - I'm hoping someone says it is because otherwise it's just going to lurk in my mind as the cognitive dissonance it has been for quite some time.

Anyhoo, I was in the bathroom once, on the jon, and I turned and bumped the toilet paper rack with my elbow. Apparently I had bumped it just right, as the full roll of toilet paper (yes, it was just put on) proceeded to completely unravel onto the floor. Of course the last bit stayed attached because it's usually glued. Of course my biggest problem was "How in the world can that happen?" then later on my problem was having all the toilet paper on the floor. Not the best place for a phenomenon, but hey, I didn't choose it!

Off the topic - is the search function not working for anyone else? I can't seem to find the thread on best physics colleges.

 

[zoobyshoe]

I think what is most fascinating about that story is that you sat there and watched it. I don't think I could have prevented myself from reaching out and stopping it in that circumstance.

 

[Chi Meson]

I'm not sure if this is physically explainable - I'm hoping someone says it is because otherwise it's just going to lurk in my mind as the cognitive dissonance it has been for quite some time.

Anyhoo, I was in the bathroom once, on the jon, and I turned and bumped the toilet paper rack with my elbow. Apparently I had bumped it just right, as the full roll of toilet paper (yes, it was just put on) proceeded to completely unravel onto the floor. Of course the last bit stayed attached because it's usually glued. Of course my biggest problem was "How in the world can that happen?" then later on my problem was having all the toilet paper on the floor. Not the best place for a phenomenon, but hey, I didn't choose it!

Off the topic - is the search function not working for anyone else? I can't seem to find the thread on best physics colleges.

This would happen at my Gran's flat (apartment) in Glasgow. I first watched it when I was 6 years old. I never saw it anywhere else. In retrospect, I figured it out: the weight of the paper between the roll and the floor creates more torque on the roll than the friction of the spindle.

My guess is that it was a "fancy" TP holder, with nice low-friction bearings as opposed to a simple rod that the TP core slides over. You need that friction otherwise what you saw will keep happening.

Oh, Zoobyshoe, it's mesmerizing! You just can't stop it! You have to wait to see if the whole roll goes!

 

[Janitor]

When I read Decker's observation about the toilet paper roll, I thought he was putting us on. But since Chi is backing Decker up on this, I am inclined to think it is for real.

It kind of reminds me about how European scientists a few centuries ago were skeptical of tales of stones falling from the sky. They chalked it up to superstitious folk myths. In that particular case (meteorites!), it turned out the laugh was on the conservative scientists--though usually it is the other way around, I would say.

Decker, the search function does not work for me either.

 

[KingNothing]

It really is amazing. I'm glad chi came along so no Janitors make me out to be a liar. It really is mesmerizing. It's still hard to picture in my head though, I mean - there would have to be an incredibly low amount of friction, seeing as the only force continually applied on it is maybe 2.5 feet of toilet paper hanging off the roll at anyone time. I'm guessing you would have to 'bump' or 'hit' the toilet paper in a line almost perfectly tangent to the circle (or cylinder, but its circular shape is all that really matters) so as to not waste any force just pushing it in or out (relative you yourself).

 

[Janitor]

In my long and distinguished career, I have never had that happen.

It would make things more difficult for me if the schools bought the low-friction devices.