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Wednesday, December 11, 2024

Meteor Showers- And kid saw one recently

 https://www.sciencealert.com/2024-closes-with-one-of-the-years-best-meteor-showers-heres-how-to-see-it

Completely unrelated picture of a meteor. 

And also kid saw one during trip... it broke apart then broke apart again. Yellowish-orange I think? 


UPDATE 0.5 - this might have some of the best accurate conservative info, not yt hyperbole: https://starwalk.space/en/news/meteor-storms and they say, meteor STORMS are so hard to predict, you never know, but in like 2028 (maybe more than 1000 per hour, AKA "ZHR"), 2094 (850 ZHR) and especially in 2098 (20,000 ZHR) there might be a big one. 

UPDATE: so this December meteor shower is nice for here, longer nights than summer at least. Need clear skies though. 200 meteors per hour is what I read, we saw a ton... I saw like 12 Friday night when it was clear. The whole family saw several. Another site says: "The Geminid Meteor Shower 2024 peaks in mid-December and can bring more than 100 meteors per hour."

UPDATE 2: There are meteor STORMS, that happen not quite randomly. There was one in 1833, where there were an estimated 50,000 to 150,000 meteors per hour... PER HOUR you read that right. Insane!  https://www.astronomytrek.com/the-great-leonids-meteor-storm-of-1833/

Great info here: https://www.youtube.com/watch?v=LBFXO9A9-xg ... he has smoke trail video from 1999-2002 Leonid shower (from Chinese video?) around time 17:00. He has a nice graph of when the Earth passes through the old Leonid trail around time 15:33. 

We'll have a better than avg showing maybe in 2027, 2028, 2033-2035, but nothing like 100K per hour. 

Old timey art of the 1833 meteor storm, part of the Leonid's leftover trail from 33 years before or something. 

Another cool story: https://www.astronomytrek.com/the-great-leonids-meteor-storm-of-1833/

Other accounts of unusually large numbers of meteors during the month of November include those from 1799, when German scientist Humboldt and his companion reported the sighting from what is now Venezuela, over which it was said that a similar event had occurred in 1766. As Humboldt stated:

“…thousands of fireballs and falling stars fell in a row for four hours, often with a brightness like Jupiter. Long smoke trails were left behind.


More crazy info... most meteors are only millimeters in width apparently. Example, Leonids that are on the large size are 10 mm across in diameter and only be of mass around 0.5 grams (0.02 oz.).  

NASA says the smaller ones are super tiny: https://leonid.arc.nasa.gov/meteor.html 

METEORS: Meteors are better known as "shooting stars": startling streaks of light that suddenly appear in the sky when a dust particle from outer space evaporates high in the Earth's atmosphere. We call the light phenomenon in the atmosphere a "meteor", while the dust particle is called a "meteoroid". 
  • Size: Most visible Leonids are between 1 mm and 1 cm in diameter. For example, a Leonid meteor of magnitude +5, which is barely visible with the naked eye in a dark sky, is caused by a meteoroid of 0.5 mm in diameter and weights only 0.00006 gram.
  • Speed That tiny particle can cause a light so bright that it can be seen over distances of hundreds of kilometers. The reason is the astronomical speed of the meteoroids. Just before they enter the Earth's atmosphere, Leonid meteoroids travel at 71 kilometers per second, or some 2,663 times as fast as a fast pitch in baseball, or, if you want, around the Earth in 3.8 minutes!

    • Source of light When meteoroids enter the Earth's atmosphere, they collide with numerous air molecules. Those collisions sputter away the outer layers of the particle, creating a vapor of sodium, iron and magnesium atoms. In subsequent collisions, electrons are knocked into orbits at larger mean distances from the nucleus of the atoms. When the electrons fall back to their rest positions, light is emitted. This is the same process as in gas discharge lamps. 
    • Colors of meteors The color of many Leonids is caused by light emitted from metal atoms from the meteoroid (blue, green, and yellow) and light emitted by atoms and molecules of the air (red). The metal atoms emit light much like in our sodium discharge lamps: sodium (Na) atoms give an orange-yellow light, iron (Fe) atoms a yellow light, magnesium (Mg) a blue-green light, ionized calcium (Ca+) atoms may add a violet hue, while molecules of atmospheric nitrogen (N2) and oxygen atoms (O) give a red light. The meteor color depends on whether the metal atom emissions or the air plasma emissions dominate.
    • Sounds Meteors do not normally cause audible sounds. Hence, they will pass by unnoticed if not seen. But watch out for hissing sounds that have been reported for very bright meteors. These sounds are thought to be due to very low frequency (VLF) radio waves interacting with the local environment. A sonic boom is sometimes heard for very bright Leonid meteors, called fireballs, that appear near your own observing site high in the sky. If the particle is larger than the mean free path of the air molecules, a high Mach number shock wave forms in front of the meteoroid. Very rarely, this shock wave penetrates deep enough in the atmosphere that it can be heard. It sounds like the sonic boom of an airplane, but as a distant rumble.
NOTE: The SMOKE is really a "train", see below. Complicated. 

PERSISTENT EMISSIONS: Bright meteors leave persistent glows.

  • Wake is the brief glow behind the meteor head. The wake is caused mainly by the green light of neutral oxygen atoms. Wakes last 1-10 seconds. Sometimes the term wake is also used to describe the area directly behind the meteor head.
  • Afterglow is the persistent metalic atom (Na, Fe,Mg) emission glow in the path of bright fireballs. The afterglow lasts a few seconds.
  • Persistent train is the long enduring emission that remains in the path of a bright fireball once the afterglow has faded. Persistent trains can last for 1-30 minutes (typically 4-6 minutes) at an apparent brightness of +4 to +5 magnitude. The optical light of these long enduring trains is from Na (sodium) and FeO (iron oxyde), from airglow-type chemistry of the recombination of oxygen atoms and ozone molecules that is catalised by sodium and iron atoms. Persistent trains last long enough to enable telescopic studies of the path of a meteor. Upper atmosphere winds distort the shape of the train.  

 

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