Starship Asterisk*

wonderboy wrote:i dont know how to upload videos or inbed them so heres a youtube clip of some strange cloud activity
explanations?
http://www.youtube.com/watch?v=rt7gE1zIt1U

This was featured as an APOD a couple of years ago. Check it out.
http://apod.nasa.gov/apod/ap111108.html

A discussion of course is also available. http://asterisk.apod.com/viewtopic.php?f=9&t=25807

I think it's sort of like a sundog, with the sun reflecting through an unusually structured cloud.

:EDIT: Ah, i was about right! I just didn't use the word "Jumping". Hey, nobody's perfect

Dog Poop Powers Park Lights.
http://www.wired.com/wiredscience/2010/ ... rk-lights/

Holy crud, I probably should have pursued that childhood fantasy of becoming a marine biologist (this was such a generic "what I want to be" science occupation for a smart, young female when I was in high school that nobody ever actually took up)



The lab photos set are the best.
http://www.flickr.com/photos/a_semenov/ ... 947932407/

Rest of the photo stream is pretty good, too.
http://www.flickr.com/photos/a_semenov/

His website has larger photos but it's a little hard to browse.
http://clione.ru/

geckzilla wrote:
Holy crud, I probably should have pursued that childhood fantasy of becoming a marine biologist (this was such a generic "what I want to be" science occupation for a smart, young female when I was in high school that nobody ever actually took up)

My eldest daughter majored in marine biology at Boston University (including a stint at Woods Hole).

She currently teaches Spanish speaking elementary kids.

ISN'T LIFE STRANGE

Every time I process a new planetary nebula from Hubble I put it on a giant collage of them with their apparent sizes being correct relative to one another and with north up orientation. I'd also like to eventually include some even wider field details that some of them have but the HST didn't cover though I'm not sure if there is any suitable data in public domain. It's not done yet and I'm not sure how many more are left for me to process but I thought I'd share the work in progress.

geckzilla wrote:
<<Every time I process a new planetary nebula from Hubble I put it on a giant collage of them with their apparent sizes being correct relative to one another and with north up orientation. It's not done yet and I'm not sure how many more are left for me to process but I thought I'd share the work in progress.>>

"I don’t do anything—much. Oh, please don’t think I sit around doing nothing! My glass collection takes up a good deal of time. Glass is something you have to take good care of. Most of them are little animals made out of glass, the tiniest little animals in the world. Mother calls them a glass menagerie!"

That's Neat!! And colorful too!
You seem to do really good in the Bigger 'space biology' stuff, geckzilla.

Stream of smashing stuff. Google street view of the LHC. Seems they put the street view cam on a tripod for this. Not sure where the person taking the pictures disappeared to for each shot...
https://www.google.com/maps?ll=46.23583 ... 2C6.055071

geckzilla wrote:Every time I process a new planetary nebula from Hubble I put it on a giant collage of them with their apparent sizes being correct relative to one another and with north up orientation. I'd also like to eventually include some even wider field details that some of them have but the HST didn't cover though I'm not sure if there is any suitable data in public domain. It's not done yet and I'm not sure how many more are left for me to process but I thought I'd share the work in progress.

Interesting, geckzilla. You say those are relative sizes? What is known about their true sizes?

Ann

That requires More Work (tm)
Measuring the distance to a planetary nebula is often difficult but some of then have their distance estimates listed at spacetelescope.org or at their Wikipedia entry. I often find myself taking guesses at how old a PN is or how far away it is based solely on visual examination. I've noticed that some are blurrier or more diffuse than others which leads me to speculate they are older and hence larger structures due to the fact that they expand outward from their parent star over time. But they are incredibly diverse and it's probably best not to generalize them like that.

Anyway, since it's hard to tell how far away they are, that means it's difficult to measure their sizes. Furthermore, if we are looking "down the barrel" at some, that is, looking at the short end, the thing could look kind of small but actually be much wider from the long end. Imagine rotating one of those bipolar nebulas around.

Edit: Wikipedia also says "A typical planetary nebula is roughly one light year across" but the use of the word "typical" amuses me because they are so diverse. "Planetary nebula" as a category seems too broad to make such a statement. And that's not even touching the fact that the "planetary" part is such a stubborn and confusing misnomer.

geckzilla wrote:Edit: Wikipedia also says "A typical planetary nebula is roughly one light year across" but the use of the word "typical" amuses me because they are so diverse. "Planetary nebula" as a category seems too broad to make such a statement.

True, but such nebula come about because a particular size of star blows up, and the range of sizes of that class of star is known to be about 0.4 to 4 solar masses, hence the force which creates the nebula is constrained to a range of values. Also, a nebula fades out after no more than about 50,000 yrs, so the maximum size it can achieve is also constrained. So putting those thoughts together, I think in this case the word "typical" refers to the possible size range of a nebula which has come about through these known mechanisms. Nevertheless, I'd agree that "roughly one light year across" is an inadequate description. A range of possible sizes would have been better.

Rob

I think it does adequately describe that they are generally a lot larger than our solar system but not really giant on a cosmic scale, though. But they are weirdly shaped! Some of them have very faint, giant structures with bright, smaller sections in the middle while others are very long in one direction.

Thanks for your answers, geckzilla and Rob.

Ann

rstevenson wrote:Also, a nebula fades out after no more than about 50,000 yrs, so the maximum size it can achieve is also constrained.

50,000 years Why, in galactic terms, that means POOF! and it's gone.

Beyond wrote:50,000 years Why, in galactic terms, that means POOF! and it's gone.

Exactly right. They are poofs of gas given off as the star sheds its atmosphere, eventually leaving just a white dwarf.

Rob

There was something called a Tweed Ride in Malmö yesterday. People dress up in old-fashioned tweed, and, if possible, bring really old bikes. I joined in yesterday, minus tweed. There were some fantastically British people in yesterday's ride, dressed up like dandies from the 1920s. The oldest bike was from 1932. We cycled for 23 kilometers and had English cream tea midways. Then there was ale and stout and that sort of thing at the end of the ride.

It was kind of fun!

Ann

A Little iness from Taiwan.
http://english.cntv.cn/program/culturee ... 4304.shtml

geckzilla wrote:Hmm, could that possibly make sandals even more dangerous than they already are? I'm curious to know just how sticky a Van der Waals force tape could get. If it's not quite sticky enough, it could get annoying.

If you have to walk, you may as well wear something comfortable. This is Just wear and sit ....I don't think its comfortable to even move.

BLAH! BLAH! Just the same ol' faldercarb that covers the earth. Nutin new there.

So for the movie Gravity, the director decided to stick to the laws of physics. It's an improbable scenario but he says he didn't make it unrealistic. No sounds of explosions, in fact no fire in explosions, and plenty of consultation with experts. Could this be a sci fi movie I can watch without internally snickering at mounds of silly liberties taken? Link to interview:
http://www.wired.com/underwire/2013/10/ ... f_gravity/

1st shutdown reactions are coming to the internet all right, you've got me curios, wtf is this "shutdown" thing? gotta look it up now...

oh so I read it's various government-funded infrastructure stopping their work because they are not paid. How fun! I liked the part where doctors refused to treat patients:

Sick patients who were scheduled to participate in research studies at the National Institute of Health’s hospital will have no other choice but to find treatment elsewhere during the government shutdown. The research hospital will be forced to turn away an estimated 200 patients, roughly 30 of them cancer-stricken children, in each week of the shutdown, NIH Director Dr. Francis Collins told the Associated Press.

And in apocalypse movies they want you to believe that doctors will help everyone they can for free, right.