Author Topic: Particle Strike Collection  (Read 64778 times)

ChrisScott

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Re: Particle Strike Collection
« Reply #30 on: January 21, 2010, 11:06:38 pm »
Hi Chris tx for all the explanations
What do we do about this one(the white line, only visible in one frame)? Is it a bleeding signal ?
Do we ignore it or is it 'something else' ?

Yes, this is just excess signal. Anything vertical is almost certainly due to signal bleeding or data processing (see my note on how our cameras don't have shutters elsewhere in the forum). We try to supress the excess signal as best we can but occasionally it does cause saturation of more columns of pixels than we are expecting and it is not removed from the movies. In our sister solar mission SOHO, the detectors bleed excess signal sideways, so you get a bright blob which extends sideways in the middle leading to many 'sightings' of UFOs in the data   :)

Thanks!

Chris.

ElisabethB

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Re: Particle Strike Collection
« Reply #31 on: February 10, 2010, 08:26:30 pm »
is this a double particle strike?
I can see two different directions.
Do we record this twice?

« Last Edit: March 16, 2010, 10:46:50 am by jules »

lpspieler

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Re: Particle Strike Collection
« Reply #32 on: February 10, 2010, 11:33:56 pm »
My impression of the tutorial examples was that also there the particle strikes did not seem to come from only one center. What's more, the timestamps only serve to point the zookeepers to certain frames in the video where we have found interesting stuff. Of course they will notice the "double center" situation even when only one timestamp has been recorded. So my personal impression was that one record would be enough.

srcrothers

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Re: Particle Strike Collection
« Reply #33 on: February 12, 2010, 10:54:40 am »
I am not sure there is any way through the interface to flag up things like this, but thanks for reporting in on the forum, this is such a useful way to select things like that which could be studied further.

Steve

jules

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Re: Particle Strike Collection
« Reply #34 on: February 13, 2010, 09:56:40 pm »
Sorry if I've missed the answer but what are the particles in a particle strike? I've seen them referred to as dust and "other debris". Now I'm wondering what other debris is out there.... ::)

ChrisScott

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Re: Particle Strike Collection
« Reply #35 on: February 14, 2010, 04:48:56 pm »
Sorry if I've missed the answer but what are the particles in a particle strike? I've seen them referred to as dust and "other debris". Now I'm wondering what other debris is out there.... ::)

Well, there's interplanetary dust, and bits of spacecraft like STEREO that get hit by that dust :) I guess what we're seeing is a combination of both.

djohnson

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Re: Particle Strike Collection
« Reply #36 on: February 24, 2010, 01:52:41 am »
Hi Chris,

Just started here today after I got the notification in my email this morning.  I'm a SOHO Sungrazer veteran (albeit with only 1 comet under my belt), so these images are very familiar to me.

I have a question about 2 "items".  One I've seen on occasion is a smearing on the very edge of the frame opposite the Sun's position, which brightens/flares and fades away sometimes in concert with activity happening on the Sun but no apparent connection (i.e. a CME happens, but the cloud hasn't reached the end of the frame when I'm seeing the flaring).  At first I thought it was similar to how the light from the brighter planets on the SOHO images would bleed into the frame when they were just outside of the edge and not visible, but in this case no planet would enter the frame.  I've noted these as optical artifacts.

The other item I saw appeared to be a fairly bright object that was moving at an angle to the stars in the video (which, I unfortunately didn't save).  To me this would either be an asteroid or a comet (however, no tail was seen, which I think would have been given the brightness of the object).  I classified this as a comet, but would like some clarification on how items such as this should be handled. 

Thanks!

Dave Johnson

mmatessa

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Re: Particle Strike Collection
« Reply #37 on: February 24, 2010, 04:43:44 am »
There's an example of a triple strike in http://solarstormwatch.com/favourites/78 at 21.60.
(three faint lines running top left to bottom right)

ChrisScott

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Re: Particle Strike Collection
« Reply #38 on: February 24, 2010, 11:34:42 am »
Hi Chris,

Just started here today after I got the notification in my email this morning.  I'm a SOHO Sungrazer veteran (albeit with only 1 comet under my belt), so these images are very familiar to me.

I have a question about 2 "items".  One I've seen on occasion is a smearing on the very edge of the frame opposite the Sun's position, which brightens/flares and fades away sometimes in concert with activity happening on the Sun but no apparent connection (i.e. a CME happens, but the cloud hasn't reached the end of the frame when I'm seeing the flaring).  At first I thought it was similar to how the light from the brighter planets on the SOHO images would bleed into the frame when they were just outside of the edge and not visible, but in this case no planet would enter the frame.  I've noted these as optical artifacts.

The other item I saw appeared to be a fairly bright object that was moving at an angle to the stars in the video (which, I unfortunately didn't save).  To me this would either be an asteroid or a comet (however, no tail was seen, which I think would have been given the brightness of the object).  I classified this as a comet, but would like some clarification on how items such as this should be handled. 

Thanks!

Dave Johnson

Hi Dave,

Thanks for your message. The flaring you describe does sound like the flaring we get when a bright object is near the edge of the field of view. Odd that no planet subsequently appeared. Could it have been on its way out? Classifying this as you did is helpful, thanks.

As for the asteroid/comet, I suggest that we classify these as 'comets' for now and try to sub-classifly them later. There may be a way of tagging such items soon so perhaps that's where we can separate comets from asteroids?

Thanks for your time!

Chris.

ElisabethB

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Re: Particle Strike Collection
« Reply #39 on: February 24, 2010, 05:56:34 pm »
There's an example of a triple strike in http://solarstormwatch.com/favourites/78 at 21.60.
(three faint lines running top left to bottom right)

hi mmatessa
this is also a particle strike. They can be very bright or very faint and everything in between.

ElisabethB

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Re: Particle Strike Collection
« Reply #40 on: February 24, 2010, 06:05:41 pm »
yes, I know, they are my favourites  ;D
But I tink it would be a good idea of including an example of a faint particle strike in the tutorial. Now it looks as if only these bright ones are the real deal and a lot of the faint ones will be labelled other.

jules

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Re: Particle Strike Collection
« Reply #41 on: February 24, 2010, 09:11:08 pm »
Good point. I remember someone (Chris?) saying that because we had found so many faint particle strikes in beta this suggested that they were more common than previously thought.

And a tip for finding faint strikes - and "getting your eye in" is to nudge the video forward frame by frame.

ChrisScott

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Re: Particle Strike Collection
« Reply #42 on: February 25, 2010, 09:50:38 am »
Good point. I remember someone (Chris?) saying that because we had found so many faint particle strikes in beta this suggested that they were more common than previously thought.

And a tip for finding faint strikes - and "getting your eye in" is to nudge the video forward frame by frame.

Yes, that's right. I recorded some more screencasts that talked about the fainter trails. I wish I'd known about the 'nudge' tip before I'd done that though, D'oh!

Chris. :-[

Astro

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Re: Particle Strike Collection
« Reply #43 on: February 25, 2010, 01:07:27 pm »
Yes, that's right. I recorded some more screencasts that talked about the fainter trails. I wish I'd known about the 'nudge' tip before I'd done that though, D'oh!

Hello

I'm not sure if it would useful for this subject, but we have written a post explaining the most famous STEREO and SOHO images phenomena, incluiding fainter trails. Unfortunately it's available just in spanish, but i promise you translate it as soon as possible.

www.clubdeastronomia.wordpress.com

we're an amateur astronomers team from different countries following the solar activity, last 2 years. for us, is an honor to help and colaborate in this wonderful project.

Best Regards

ElisabethB

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Re: Particle Strike Collection
« Reply #44 on: February 25, 2010, 07:13:57 pm »
optical effect ? and what could cause this
http://solarstormwatch.com/favourites/193
« Last Edit: February 25, 2010, 07:15:28 pm by ElisabethB »