APOD: Pelican Nebula Close Up (2010 Aug 19)

Post a reply


This question is a means of preventing automated form submissions by spambots.
Smilies
:D :) :ssmile: :( :o :shock: :? 8-) :lol2: :x :P :oops: :cry: :evil: :roll: :wink: :!: :?: :idea: :arrow: :| :mrgreen:
View more smilies

BBCode is ON
[img] is ON
[url] is ON
Smilies are ON

Topic review
   

Expand view Topic review: APOD: Pelican Nebula Close Up (2010 Aug 19)

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by starman » Fri Aug 20, 2010 9:25 am

"It would be great to see a star forming"... well, now you can!
Within the past few days, a new star has appeared in this very region!
And a new star, not a nova. Actually, a formerly very faint star (18-19m) has just increased by about 5 magnitudes because the circumstellar disc that encircles it has just dumped a huge amount of material down onto the star. This is what is known as an FU Orionis star. The position of the object is: RA 20h 58m 17.03s +43° 53' 43.4" and its name is LkHA 188 G4 (i.e., it's star no. 188 in the Lick observatory catalogue of H-alpha stars... or to be more precise it's the fourth in a group of h-alpha stars that surround LkHA188!) - this whole region is an area of intense star formation, and there are many others in Cygnus, one of the other more active ones being the area a few degrees North of Deneb.
The erupting FU Ori star is currently about magnitude 13, but it could brighten up a bit more. FU Ori stars normally have amplitudes of about 6m.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by neufer » Thu Aug 19, 2010 7:43 pm

León wrote:
Giuseppe Baretti said that after Galileo's abjuration [he] said the phrase "Eppur si muove"
http://en.wikipedia.org/wiki/E_pur_si_muove wrote:
<<The Italian phrase "Eppur si muove" means And yet it moves (Nonetheless, it moves). Legend has it that the Italian mathematician, physicist and philosopher Galileo Galilei muttered this phrase after being forced to recant in 1633, before the Inquisition, his belief that the Earth moves around the Sun. It is occasionally used in modern speech to indicate that although publicly someone who is in a knowledgeable position may discount or deny something, that does not stop it from being true.

At the time of Galileo's trial, the dominant view among theologians, philosophers and scientists was that the Earth is stationary, indeed the center of the universe. Galileo's adversaries brought the charge of heresy, then punishable by death, before the Inquisition. Since Galileo recanted, he was only put under house arrest until his death, nine years after the trial.

There is no contemporary evidence that Galileo muttered this expression at his trial; it would certainly have been highly imprudent for him to have done so. The earliest biography of Galileo, written by his disciple Vincenzio Viviani, does not mention this phrase, and depicts Galileo as having sincerely recanted. The legend first became widely published in Querelles Littéraires (1761), recounting a tale published by an Italian living in London in 1757 (124 years after the supposed utterance). In 1911, the famous line was found on a Spanish painting owned by a Belgian family, dated 1643 or 1645. The painting is obviously ahistorical, since it depicts Galileo in a dungeon, but nonetheless proves that some variants of the "E pur si muove" legend had been circulating for over a century before it was published, perhaps even in his own lifetime.>>
http://www.seinfeldscripts.com/TheNote.html wrote:
George: I think it moved.

Jerry: Moved?

George: It may have moved, I don't know.

Jerry: I'm sure it didn't move.

George: It moved! It was imperceptible but I felt it.

Jerry: Maybe it just wanted to change positions?
__ You know, shift to the other side.

George: No, no. It wasn't a shift, I've shifted, this was a move.

Jerry: Okay, so what if it moved?

George: That's the sign! The test; if a man makes it move.

Jerry: That's not the test.
_ Contact is the test, if it moves as a result of contact.

George: You think it's contact? It has to be touched?

Jerry: That's what a gym teacher once told me.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by bystander » Thu Aug 19, 2010 6:32 pm

León wrote:Giuseppe Baretti said that after Galileo's abjuration said the phrase "Eppur si muove"
I apologize, I missed the connection. :oops: I remove my objections.

But, still, if you are quoting someone you need to attribute the quote, and if not in english, a translation is still in order.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 6:30 pm

rstevenson wrote:
bystander wrote:
León wrote:eppur si muove
per Google Translate
yet it does move
A quote from Stephen Jay Gould seems appropriate right about now... "A man does not attain the status of Galileo merely because he is persecuted; he must also be right." :P

Rob
Of course it is as you say

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 6:23 pm

bystander wrote:
León wrote:eppur si muove
per Google Translate
yet it does move
Giuseppe Baretti said that after Galileo's abjuration said the phrase "Eppur si muove"

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by rstevenson » Thu Aug 19, 2010 6:22 pm

bystander wrote:
León wrote:eppur si muove
per Google Translate
yet it does move
A quote from Stephen Jay Gould seems appropriate right about now... "A man does not attain the status of Galileo merely because he is persecuted; he must also be right." :P

Rob

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by bystander » Thu Aug 19, 2010 6:14 pm

León wrote:eppur si muove
per Google Translate
yet it does move
Rule 2: wrote:
Board Language

This board is an English only board. All posts must be in English. We understand that English is not the primary language of many of our posters, but we do not have the resources to support a multilingual board. Posts in other languages may be removed and penalties imposed.
Please read The Rules!

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 6:03 pm

eppur si muove

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by bystander » Thu Aug 19, 2010 4:47 pm

León wrote:I think you should read again and not answer with such haste
This is not the first time you have made such proposals. If you have a question, then ask it, but please do not phrase it as an alternative theory.

Please read The Rules!

bystander
Forum Moderator

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 4:41 pm

Chris Peterson wrote:
rstevenson wrote:As for this being an unscientific discussion, and therefore inappropriate to the Asterisk, I beg to differ. I can see exactly this question being proposed in an Astronomy class, the purpose being to prompt students to go off and find out all sorts of things to either support or reject the proposal.
I agree. It could be proposed as a question, and discussed for its merits. But that isn't the same thing as an outright proposal, with no support. But maybe I'm just reading something into a less than perfect translation from somebody whose first language is different from that of this forum.
I think you should read again and not answer with such haste

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by bystander » Thu Aug 19, 2010 4:37 pm

León wrote:Image
APOD: Dust Pillar of the Carina Nebula (2010 Apr 26)
http://asterisk.apod.com/vie ... =9&t=19192

Re: León, Chris Peterson, rstevenson
[color=#FF0000][b]Rule 15:[/b][/color] wrote:
Alternative Theories and Conspiracy Theories

This board concentrates on the mainstream or consensus view of cosmology. Alternative theories and conspiracy theories are not discussed here. We may decide to allow limited discussion of these at some later date. For now, however, we ask that you take these discussions to other boards that allow such discussions.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by Chris Peterson » Thu Aug 19, 2010 4:29 pm

rstevenson wrote:As for this being an unscientific discussion, and therefore inappropriate to the Asterisk, I beg to differ. I can see exactly this question being proposed in an Astronomy class, the purpose being to prompt students to go off and find out all sorts of things to either support or reject the proposal.
I agree. It could be proposed as a question, and discussed for its merits. But that isn't the same thing as an outright proposal, with no support. But maybe I'm just reading something into a less than perfect translation from somebody whose first language is different from that of this forum.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by rstevenson » Thu Aug 19, 2010 3:44 pm

Chris Peterson wrote:
rstevenson wrote:
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
You're thinking of hydrogen burning in stars. But there are also the processes of helium burning, carbon burning, neon burning, oxygen burning and silicon burning, all of which contribute to the creation of heavier elements. See the Wikipedia page on Nucleosynthesis.
Yes, but AFAIK there are no stars that form without hydrogen as their main constituent. Stars evolve to states that fuse something other than hydrogen, but they never start that way.
True, but I think León was wondering if a star could form without hydrogen, and if so, would nucleosynthesis progress. The reason stars seem to always include so much hydrogen is simply that there is so much of it to include. But if we imagine a region of space containing sufficient gas and dust, which happens to contain little or no hydrogen, then I suppose (under those extremely unlikely conditions) a star could indeed form. And if it formed, I see no reason why some form of nucleosynthesis could not happen, though likely not the usual processes and not to the same extent.

[added moments later, after I saw Chris' post above]

As for this being an unscientific discussion, and therefore inappropriate to the Asterisk, I beg to differ. I can see exactly this question being proposed in an Astronomy class, the purpose being to prompt students to go off and find out all sorts of things to either support or reject the proposal. The main thing they'd need to do in support of the idea is propose a mechanism by which a cloud of gas and dust sufficently large to coalesce into a star could form without including any significant amount of hydrogen. I suspect it's not possible, but that doesn't make this an unscientific discussion. Perhaps you know it's not possible?

Rob

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by Chris Peterson » Thu Aug 19, 2010 3:41 pm

León wrote:Yes, even what is known of the existence of hydrogen required for the birth of the star, personally I propose an alternative, stars that look as such without synthesize elements, is it possible? that's what I propose.
Yes, I get that this is your proposal. I would simply argue that it, and your other points above, are utterly without theoretical or observational support. In short, as proposed, they are unscientific and out of place in this discussion. There are forums for non-scientific speculation, but for the most part this one tries to avoid that.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 3:29 pm

Chris Peterson wrote:
rstevenson wrote:
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
You're thinking of hydrogen burning in stars. But there are also the processes of helium burning, carbon burning, neon burning, oxygen burning and silicon burning, all of which contribute to the creation of heavier elements. See the Wikipedia page on Nucleosynthesis.
Yes, but AFAIK there are no stars that form without hydrogen as their main constituent. Stars evolve to states that fuse something other than hydrogen, but they never start that way.
Yes, even what is known of the existence of hydrogen required for the birth of the star, personally I propose an alternative, stars that look as such without synthesize elements, is it possible? that's what I propose.

With two protons and two neutrons we got to Helio and always will be needed later proliferation of neutrons from hydrogen only, except for replication and / or tripling as when carbon is accessed from three helios.

This is possible if there is no enough hydrogen, or asufre from two oxygen atoms.
Understand the idea?
Yes, hasta lo conocido se exigía la existencia de hidrógeno para el nacimiento de la estrella, personalmente propongo otra alternativa, estrellas que lucen como tales sin sintetizar elementos, ¿será esto posible? eso es lo que propongo.

Thus, a star is born despite missing hydrogen? Star that is not synthesize elements?

Con dos protones y dos neutrones llegamos al Helio y siempre en adelante será necesaria la proliferación de neutrones sólo proveniente del hidrógeno, salvo por duplicación y/ o triplicación como cuando se accede el carbono a partir de tres helios.
Esto es posible si no hubiere hidrógeno suficiente, o al asufre a partir de dos oxígenos.
¿Se comprende la idea?
Así, nace la estrella a pesar de faltar hidrógeno? Es estrella la que no sintetiza elementos?

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by Chris Peterson » Thu Aug 19, 2010 2:58 pm

rstevenson wrote:
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
You're thinking of hydrogen burning in stars. But there are also the processes of helium burning, carbon burning, neon burning, oxygen burning and silicon burning, all of which contribute to the creation of heavier elements. See the Wikipedia page on Nucleosynthesis.
Yes, but AFAIK there are no stars that form without hydrogen as their main constituent. Stars evolve to states that fuse something other than hydrogen, but they never start that way.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by rstevenson » Thu Aug 19, 2010 2:08 pm

León wrote:... 3.-producing synthesis of elements will require the presence of hydrogen feedstock neutron.
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
You're thinking of hydrogen burning in stars. But there are also the processes of helium burning, carbon burning, neon burning, oxygen burning and silicon burning, all of which contribute to the creation of heavier elements. See the Wikipedia page on Nucleosynthesis.

Rob

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by orin stepanek » Thu Aug 19, 2010 1:52 pm

León wrote:For a time, from the excellent pictures provided by the new telescopes I have watched the birth of stars and have concluded that I note below. Tentative conclusion that left readers considering accepting any corrections.
1.-The stars should leave a million years to synthesize elements
2.-So I understand that the star is formed from elements in the plasma state, which behaves like a star shining in the sky without producing a synthesis.
3.-producing synthesis of elements will require the presence of hydrogen feedstock neutron.
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
5.The image can be seen as ionized peaks separating after forming long strands brilliant occurs to me are a result of transit of electricity due to which the Winding cord ends to form the sphere.
Image in both can be seen dark tendril Image
Nice photo! 8-)
http://www.flickr.com/photos/hubble-her ... 544909404/
Looks like HH901/902 are showing some light; unless that is a reflection from background stars.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by orin stepanek » Thu Aug 19, 2010 1:43 pm

neufer wrote:
orin stepanek wrote:
You can see the twin jets emerging from the tip of the tendril pretty good in this view.
http://apod.nasa.gov/apod/ap061227.html 8-)

It would be neat to catch a protostar light up. :)
. Frodo star: Elijah Wood
Image
:) Nice find! 8-)

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by León » Thu Aug 19, 2010 1:22 pm

For a time, from the excellent pictures provided by the new telescopes I have watched the birth of stars and have concluded that I note below. Tentative conclusion that left readers considering accepting any corrections.
1.-The stars should leave a million years to synthesize elements
2.-So I understand that the star is formed from elements in the plasma state, which behaves like a star shining in the sky without producing a synthesis.
3.-producing synthesis of elements will require the presence of hydrogen feedstock neutron.
4.-So, the stars we see formed from dust and / or molecular matter, if they lack hydrogen, may shine like stars for its plasma state, but may not synthesize elements from the duplication of atoms.
5.The image can be seen as ionized peaks separating after forming long strands brilliant occurs to me are a result of transit of electricity due to which the Winding cord ends to form the sphere.
Image in both can be seen dark tendril Image

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by neufer » Thu Aug 19, 2010 1:19 pm

orin stepanek wrote:
You can see the twin jets emerging from the tip of the tendril pretty good in this view.
http://apod.nasa.gov/apod/ap061227.html 8-)

It would be neat to catch a protostar light up. :)
. Frodo star: Elijah Wood
Image

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by orin stepanek » Thu Aug 19, 2010 12:55 pm

You can see the twin jets emerging from the tip of the tendril pretty good in this view. http://apod.nasa.gov/apod/ap061227.html 8-) It would be neat to catch a protostar light up. :)

ET phone home.

by neufer » Thu Aug 19, 2010 11:48 am

APOD Robot wrote:Image Pelican Nebula Close Up

But stars are also forming within the dark shapes. In fact, twin jets emerging from the tip of the central, dark tendril are the telltale signs of an embedded protostar cataloged as Herbig-Haro 555.
http://asterisk.apod.com/vie ... ns#p123532
http://en.wikipedia.org/wiki/555_%28telephone_number%29 wrote:
<<Telephone numbers with the prefix 555 are widely used for fictitious telephone numbers in North American television shows, films, computer games, and other media. Not all numbers that begin with 555 are fictional—for example, 555-1212 is one of the standard numbers for directory assistance throughout the United States and Canada. In fact, only 555-0100 through 555-0199 are now specifically reserved for fictional use, with the other numbers having been released for actual assignment.

The phone companies began encouraging the producers of television shows and movies to use the 555 prefix for fictional telephone numbers, roughly during the 1960s. One of the earliest uses of a 555 number can be seen in Panic in Year Zero! (1962), with 555-2106. In older television shows from the 1950s or 1960s, "KLondike 5" or "KLamath 5" was used, as at the time the telephone exchanges used letters and numbers in phone numbers. More recent works set in this period typically use this convention as well. For example, Dr. Emmett Brown's 1955 phone number in Back to the Future is "KLondike 5-4385".

Before "555" or "KLondike 5" gained broad usage, and before touchtone phones became standard, scriptwriters would sometimes invent fake exchanges starting with words like "QUincy" or "Zebra". The letters "Q" and "Z" were not used on the old dial phones.

555 use is only restricted in North America. Neglecting this fact resulted in a lawsuit in the late 1980s: in his daily The Far Side panel, cartoonist Gary Larson included a graffiti of a 555 number by which prank calls could be made to Satan. When the panel was printed in Australia (where 555 was at the time a standard exchange), the owner of the 555 number became the subject of much harassment, and sued Larson and his syndicate for defamation. The suit was unsuccessful.>>

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by Scottyo3921 » Thu Aug 19, 2010 7:34 am

That's not a pelican, it's a deer! A cute Santa's red-nosed reindeer, in right profile.

A pelideer.

Re: APOD: Pelican Nebula Close Up (2010 Aug 19)

by Ann » Thu Aug 19, 2010 5:43 am

Yes, that's beautiful!

Ann

Top