persieds question

[timetraveller]

Hiya guys and gals

Did anybody who was lucky enough to be able to see any of the Persieds last night notice any strange tracks from them ?

I observed several short but very wide tracks a couple almost 1/4 of a degree wide but quite short in duration Im just wondering if the coma of swift tuttle is beginning to break up and what i saw was large pieces of the comet making those tracks

regards Pete

[mjpfc]

I saw about 8 that left bright tracks that remained for a time when they had gone, 3 of which lasted for over 4 seconds, and two of these where pretty thick. (And rather greenish - Magnesium).

I saw 68 in total, but few of these were very faint. Either my sky was filtering out just about all the faint ones or there are mainly descent sized, or slower moving bits in this part of the stream?

(This is of course the UK so I'll be voting for the sky myself).

Mick IOW

[Capricorn]

Read about 2-3 weeks ago that one of the characteristics of the Perseids is that they leave persistant trails unlike most of the others.

So if this is what you are seeing then it is expected for this meteor shower.

Not a clue why this is, but seems that it is.

[badgerchap]

I've seen Perseids for a few years in a row now, and you usually get a few like this. In fact, last year, there seemed to be more like this than smaller, thinner ones. What I was amazed at this year was how many non-Perseids I saw, i.e. ones coming from a direction way away from the radiant. Anyone else get this?

[Llamanaut]

kappa cygnids were active too around the same time werent they? the perseids i saw this year were mainly wide, short duration with greeny/ yellowy trails, a few were white and blue but not many

[Starman]

The persistent bit is called a meteor train. The trail is the initial streak. The process by which light is emitted from the meteoroid as it comes through the atmosphere is via ionisation of the atmosphere and atoms vapourised off the meteoroid itself. The colours seen are therefore from atoms in our atmosphere (oxygen and nitrogen) as well as the constituent elements found in the meteoroid.

A bright event will leave a lot of excited atoms behind it. A bit like a corridor of ionisation. This 'train' can take several seconds to fade away and looks like a ghostly vapour trail. Being within the Earth's atmopshere, this can also become distorted due to high altitude winds.

The Perseids is the main shower active at this time of year but by no means the only one active. There's a tendency to report any streak seen in the sky or photographed, as a Perseid but this is plain wrong. Many of the other showers active are either low rate or have low altitude radiants which means that the number of meteors you'll see from them will be correspondingly low. However, taken together, these weak showers raise the probability of seeing a meteor in the night sky to levels which greatly augment the Perseids.

The peak of the Perseids is quite sharp and either side of the maxiumum date the rates fall off quite rapidly to between 10-20 meteors per hour. This is a zenithal hourly rate and so doesn't represent what you'll actually see.

In addition to all of the other showers active at this time of year, there is still the potential to see a completely random meteor which is known as a sporadic.