Starship Asterisk*

garry wrote:Why is it when we see something we do not understand or explain, we automatically think it must be a black hole?

garry wrote:
Why is it when we see something we do not understand or explain, we automatically think it must be a black hole? What such small thinking!

http://www.physicsoftheuniverse.com/topics_blackholes.html wrote:
<<Black holes are a phenomenon predicted by Albert Einstein's General Theory of Relativity, which was published in 1916. In fact, the idea of a black hole was proposed as early as 1783 by the amateur British astronomer John Michell (and independently by the Frenchman Pierre-Simon Laplace in 1795).

Ironically, Einstein himself did not believe in the existence of black holes, and he strongly resisted the idea, even though his own theory predicted them. The general scientific consensus is now that black holes do in fact exist, and that they are actually one of the most important features of our universe. Astronomers have detected them indirectly in enough different ways that there is little doubt of their existence.

A black hole (the phrase is usually credited to the American physicist John Wheeler in 1967, and is certainly a distinct improvement on the original label of “gravitationally completely collapsed objects”) is a region of space in which the gravitational field is so powerful that nothing, including electromagnetic radiation such as visible light, can escape its pull - a kind of bottomless pit in space-time.
At its centre lies an infinitely small, infinitely dense singularity, a place where the normal laws of physics break down. As the comedian Steven Wright once remarked: “Black holes are where God divided by zero”.>>

garry wrote:
If the effects of universe can be only explained by black holes, dark matter & gravity then we are already stunted in our growth of understanding.
We only know an extremely small percentage about how our universe works yet we will not consider new ideas or theories.

Beyond wrote:
Neufer, there seems to be something a little amiss here. In the right hand picture i see lavendar, not blue. Also, in the left hand picture i see a lavanderish color in the middle of the blue in the center of the Crab nebula. Do you need to re-word your wording, or am i just seeing lavandar that isn't really there??

Howdy Doody's Dilly Dally wiggled
his ears when he was frustrated.

The energy stored in these beams is incredible, crushing our imagination into dust: for a time, they shone with the light of a trillion Suns!

neufer wrote:

Andy1963 wrote:
What can we determine about the space between this GRB and us given that the gamma rays arrived nearly two days before the LF radio signal?

This is not a propagation issue so much as a formation issue.

Synchrotron radiation particles start out with very high energies in very high magnetic fields
and, thereby, begin generating very high 'gamma ray' frequencies.

Worn out synchrotron radiation particles in more distant weaker magnetic fields
eventually generate the visible & radio frequencies.

http://en.wikipedia.org/wiki/Synchrotron_radiation wrote:

The blue light from the jet emerging from M87's bright AGN core, towards the lower right, is due to synchrotron radiation.

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The bluish glow from the central region of the Crab Nebula is due to synchrotron radiation.

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Andy1963 wrote:
And at what stage would neutrinos be recorded, if any?

It is not clear how neutrinos might be generated in this situation.

[paraphrase of APOD Robot]:
A symphony of planet-wide observations began abruptly when Swift detected a burst of high-frequency gamma-rays from GRB 110328A.
Twelve hours after the initial fanfare astronomers chimed in with a mid-range observation of the optical counterpart.
Early the next day the explosion was picked up in baritone low-frequencies.
Later many optical telescopes began playing along by tracking the optical counterpart.
The unusual source was spotted at a higher register by Chandra and was intermittently followed in the even more soprano-like gamma-ray range for a week.
Joining the chorus, Hubble Space Telescope recorded this image in optical and infrared light…this explosion occurred when the universe was about two thirds of its present age.
The puzzling features of the distant detonation are still being explored.

JohnD wrote:See the Chandra website article: http://chandra.harvard.edu/press/04_rel ... 21804.html
Quote, "The odds stellar tidal disruption will happen in a typical galaxy are low, about one in 10,000 annually."
But it went on to say that,"If it happened at the center of the Milky Way Galaxy, 26,000 light-years from Earth, the resulting X-ray outburst would be about 50,000 times brighter than the brightest X-ray source in our galaxy, beside the Sun, but it would not pose a threat to Earth."

Really? That source is 4 million light years away and from us to the centre of the Milky Way is about 25000 ly. So however faint the radiation was it would be 4 million squared/2500 squared stronger if it happened there. That's 25,000 times more intense radiation. That number is half the factor suggested on Chandra - where did I go wrong?

Whatever, if the radiation was emitted as a jet (see Chandra and the BA's essay) which would concentrate it in a beam, would an inverse square law still apply?

one3xi wrote:Ok I understand this paticular event but what about stars going out or firing up for the first time...again give the numbers why is there no nightly light show?

Indigo_Sunrise wrote:

Beyond wrote:I didn't get the ' source flared' at all, though.

Hi Beyond, did you not see Phil's original post on the flare? Hope this helps!


And this image fascinates me! (I agree with owlice, too: the description seems like it was a ton of fun to write!)

one3xi wrote:Ok I understand this paticular event but what about stars going out or firing up for the first time...again give the numbers why is there no nightly light show?

one3xi wrote:
Question...Given the enormous number of stars in the universe...Why don't we see this happening all of the time? ... it seems to me that just looking into the night sky we should see flashes of light and stars blinking out all over the place...any answers?

http://en.wikipedia.org/wiki/Radio_Bart wrote:

<<The Simpson family are busy preparing for Bart's birthday party. Homer sees a commercial on television for a prank microphone called the Superstar Celebrity Microphone that can be used to tap into localized radio systems and instantly decides to buy one for Bart. Subsequently, Bart experiences a crushingly disappointing birthday party when all his gifts turn out to be useless things like a cactus, a label maker, and a new suit. At first, he is also disappointed by the microphone, but later finds a use for it in creating practical jokes, such as tricking the Flanders children into believing that God is talking to them, listening in on Lisa and Janey's conversations about boys, and persuading Homer that martians are invading the Earth.

Bart throws a radio down a well and speaks through it with the microphone, tricking the townspeople into thinking an orphan named Timmy O'Toole has fallen down the well. Although they are unable to get "Timmy" out, as the well is too small for any adult to fit in, the entire town offers moral support and do everything they can to give him hope. Krusty even gets musician Sting to join other celebrities in recording a charity single, "We're Sending Our Love Down the Well". However, Bart—after realizing that his name is on the radio thanks to his label-maker—falls into the well while trying to retrieve it. When the townspeople find out, he confesses that Timmy O'Toole does not exist. Angry at being tricked, the townspeople leave Bart in the well. At the same time, "We're Sending Our Love Down The Well" dramatically falls off the number one spot to be replaced by "I Do Believe We're Naked" by Funky C, Funky Do. Despite efforts by Homer and Marge to mobilize a rescue operation, the entire town remains outraged at Bart and refuse to help. Finally, Homer has had enough—he decides to dig a tunnel and rescue Bart himself. Groundskeeper Willie sees this and joins Homer. With a little help from Sting, and several residents who put their anger aside, an excavation operation is started. A regretful Bart is finally rescued and Willie puts up a small warning sign near the well the next morning to prevent future incidents.>>

Andy1963 wrote:
What can we determine about the space between this GRB and us given that the gamma rays arrived nearly two days before the LF radio signal?

http://en.wikipedia.org/wiki/Synchrotron_radiation wrote:

The blue light from the jet emerging from M87's bright AGN core, towards the lower right, is due to synchrotron radiation.

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The bluish glow from the central region of the Crab Nebula is due to synchrotron radiation.

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Andy1963 wrote:
And at what stage would neutrinos be recorded, if any?

Beyond wrote:I didn't get the ' source flared' at all, though.