Astrophysics and Cosmology - Discuss the Universe here

[onan]

but the universe has a dark sense of humor it seems

OR... an unjustified poor aim.

[Agent : Orange]

OR... an unjustified poor aim.

There's the potential here for a great comment about god writing his name in the snow, but sadly it's just too early in the morning for me.

[Agent : Orange]

Firing lasers through plasma could efficiently accelerate electrons and eliminate the need for large particle accelerators
http://phys.org/news/2014-05-combining-lasers-particle-kilometers-meters.html
If it turns out to be practical this will revolutionize particle physics

[aldousburbank]

Firing lasers through plasma could efficiently accelerate electrons and eliminate the need for large particle accelerators
http://phys.org/news/2014-05-combining-lasers-particle-kilometers-meters.html
If it turns out to be practical this will revolutionize particle physics

[Mind Flayer Monk]

Firing lasers through plasma could efficiently accelerate electrons and eliminate the need for large particle accelerators
http://phys.org/news/2014-05-combining-lasers-particle-kilometers-meters.html
If it turns out to be practical this will revolutionize particle physics

I see the man in charge is Dr. Alan Parsons... *pinky finger to mouth*

[Agent : Orange]

Bahaha! Perfect timing

[area51drone]

Firing lasers through plasma could efficiently accelerate electrons and eliminate the need for large particle accelerators
http://phys.org/news/2014-05-combining-lasers-particle-kilometers-meters.html
If it turns out to be practical this will revolutionize particle physics

Kids will now be making element 115 in their garage.   And to think, we know "everything up to within a second of the big bang".   Yeah right.

[Agent : Orange]

Kids will now be making element 115 in their garage.   And to think, we know "everything up to within a second of the big bang".   Yeah right.

It's pretty astonishing. The question becomes how efficient those lasers can get and how rapidly they can be pulsed.

[Agent : Orange]

Detecting radio emission from meteors. Interesting!
http://arxiv.org/abs/1405.6772

[area51drone]

Detecting radio emission from meteors. Interesting!
http://arxiv.org/abs/1405.6772

To be truthful, I didn't read the paper, I just don't have time.  But why is this interesting?

[Agent : Orange]

To be truthful, I didn't read the paper, I just don't have time.  But why is this interesting?

They did an all-sky visual observation and were able to match up the passing of a meteor with a non-thermal (ie, not a result of burning meteor) radio chirp. That's pretty cool.

From the abstract, "these transients correlate both spatially and temporally with large meteors (fireballs), and their signatures suggest that fireballs emit a previously undiscovered low frequency, non-thermal pulse. This emission provides a new probe into the physics of meteors and identifies a new form of naturally occurring radio transient foreground."

[area51drone]

They did an all-sky visual observation and were able to match up the passing of a meteor with a non-thermal (ie, not a result of burning meteor) radio chirp. That's pretty cool.

From the abstract, "these transients correlate both spatially and temporally with large meteors (fireballs), and their signatures suggest that fireballs emit a previously undiscovered low frequency, non-thermal pulse. This emission provides a new probe into the physics of meteors and identifies a new form of naturally occurring radio transient foreground."

But this should not be particularly surprising.  Aren't many asteroids made of iron?  Especially the ones that become meteors and survive to become a big fireball?   Iron passing through the earth's magnetic field would surely create radio waves.   So I don't get the big wow factor in this.

[Agent : Orange]

But this should not be particularly surprising.  Aren't many asteroids made of iron?  Especially the ones that become meteors and survive to become a big fireball?   Iron passing through the earth's magnetic field would surely create radio waves.   So I don't get the big wow factor in this.

Not really a big wow factor, just a paper from the arxiv I thought was interesting.

No one has seen these kinds of tails at such low radio frequencies and they behave differently than the other kinds of tails that have been seen before (scattering and specular tails) which scatter radio waves.

The implication is that this is another foreground contaminant which has to be removed from transient object searches and may be responsible for the mysterious fast radio bursts which have been getting some attention in the literature lately.

[area51drone]

The implication is that this is another foreground contaminant which has to be removed from transient object searches and may be responsible for the mysterious fast radio bursts which have been getting some attention in the literature lately.

What are you saying here... that astronomers using radio telescopes looking at distant stars are concerned about radio bursts they can't explain, or that we have scientists actively looking for UFO's?   :

Don't they say that tons of material (dust, small particles) are constantly falling on the earth at any given time?  Wouldn't any of this material that is made up of iron create some kind of radio signature?

[Agent : Orange]

What are you saying here... that astronomers using radio telescopes looking at distant stars are concerned about radio bursts they can't explain

Yes

Don't they say that tons of material (dust, small particles) are constantly falling on the earth at any given time?  Wouldn't any of this material that is made up of iron create some kind of radio signature?

Not all of it is iron, it makes up background and small events are responsible for smaller effects. These are new signatures and related to meteors

[zeebo]

Kids will now be making element 115 in their garage....

Reminds me of an old Jetsons episode where the kid got in trouble for splitting atoms all over the floor.

[zeebo]

WTF? Is this for real?

Astronomers Find First Evidence of Other Universes

[Agent : Orange]

WTF? Is this for real?

Astronomers Find First Evidence of Other Universes

Unlikely. But the claim has been around for a while, it's from one of Roger Penrose's projects. The observations he claims support his ideas are very low likelihood statistically, which is to say there are many more explanations for ring like features in the CMB other than Penrose's explanation which is admittedly pretty significant, if true. It's an exciting and attention grabbing idea, that probably has some truth to it, but it's hard to really take it seriously until it's put on more firm ground. To do that we need better observations of the CMB than Planck gave which may be quite a while down the line.

[area51drone]

Unlikely. But the claim has been around for a while, it's from one of Roger Penrose's projects. The observations he claims support his ideas are very low likelihood statistically, which is to say there are many more explanations for ring like features in the CMB other than Penrose's explanation which is admittedly pretty significant, if true. It's an exciting and attention grabbing idea, that probably has some truth to it, but it's hard to really take it seriously until it's put on more firm ground. To do that we need better observations of the CMB than Planck gave which may be quite a while down the line.

Just curious, what are the other likely explanations for the ring features?

[Agent : Orange]

Just curious, what are the other likely explanations for the ring features?

The question is whether or not those rings have really been detected, since they are not considered a slam-dunk by any stretch of the imagination and have been quite a controversial claim (http://www.wired.com/2011/05/no-cmb-circles/). It is also not clear if such rings are statistically outlawed by the standard cosmological model, which they do not seem to be.

Rings and other such patterns in the CMB are usually considered the work of gravitational effects from the age before the emission of the cosmic microwave background (earlier than 300,000 years after the big bang). Lensing of the CMB can produce rings and other distortions, and from even earlier times gravitational waves can imprint these kinds of signatures on the CMB as well.

Regardless of the explanation the ring features (if they are real) are very interesting and warrant further study even if they can be explained by less exotic means.

[Agent : Orange]

Found this interesting paper today, which I thought I'd share. Not connected to anything on the discussion block, just a neat idea.
http://arxiv.org/abs/1406.0323

Abstract: The nearly equal lunar and solar angular sizes as subtended at the Earth is generally regarded as a coincidence. This is, however, an incidental consequence of the tidal forces from these bodies being comparable. Comparable magnitudes implies strong temporal modulation, as the forcing frequencies are nearly but not precisely equal. We suggest that on the basis of paleogeographic reconstructions, in the Devonian period, when the first tetrapods appeared on land, a large tidal range would accompany these modulated tides. This would have been conducive to the formation of a network of isolated tidal pools, lending support to A.S. Romer's classic idea that the evaporation of shallow pools was an evolutionary impetus for the development of chiridian limbs in aquatic tetrapodomorphs. Romer saw this as the reason for the existence of limbs, but strong selection pressure for terrestrial navigation would have been present even if the limbs were aquatic in origin. Since even a modest difference in the Moon's angular size relative to the Sun's would lead to a qualitatively different tidal modulation, the fact that we live on a planet with a Sun and Moon of close apparent size is not entirely coincidental: it may have an anthropic basis.

[area51drone]

The question is whether or not those rings have really been detected, since they are not considered a slam-dunk by any stretch of the imagination and have been quite a controversial claim

Sounds like something else we've heard of with the name of Art Bell's former show..

(http://www.wired.com/2011/05/no-cmb-circles/). It is also not clear if such rings are statistically outlawed by the standard cosmological model, which they do not seem to be.

Six of one, half dozen of the other when it comes to "questionable" statistics like CMB rings and lens shear, eh?

[Agent : Orange]

Six of one, half dozen of the other when it comes to "questionable" statistics like CMB rings and lens shear, eh?

When you're trying to separate a tiny signal from noisy data you have to be careful and cautious.
Question everything.

[Agent : Orange]

"Discovery of a Thorne-Zytkow object candidate in the small magellanic cloud"
Since the 1970s it was conjectured that a red giant star could absorb a companion neutron star, and the pair could then go on to survive, and settle down into a hybrid star in equilibrium, a red giant atmosphere surrounding a neutron degenerate core. New observations show such an object may actually have been observed! Exciting. Incidentally, the Thorne is Kip Thorne, an expert in GR who helped Carl Sagan write about the wormhole machine from the novel/movie Contact.
http://arxiv.org/abs/1406.0001

Abstract: Thorne-Zytkow objects (TZOs) are a theoretical class of star in which a compact neutron star is surrounded by a large, diffuse envelope. Supergiant TZOs are predicted to be almost identical in appearance to red supergiants (RSGs). The best features that can be used at present to distinguish TZOs from the general RSG population are the unusually strong heavy-element and Li lines present in their spectra, products of the star's fully convective envelope linking the photosphere with the extraordinarily hot burning region in the vicinity of the neutron star core. Here we present our discovery of a TZO candidate in the Small Magellanic Cloud. It is the first star to display the distinctive chemical profile of anomalous element enhancements thought to be unique to TZOs. The positive detection of a TZO will provide the first direct evidence for a completely new model of stellar interiors, a theoretically predicted fate for massive binary systems, and never-before-seen nucleosynthesis processes that would offer a new channel for Li and heavy-element production in our universe.

[Stellar]

I really like this, physics is like an onion with all it's layers, but it doesn't hurt your eyes.

You sure about this:

Here is my Rap song about Axiom Unification Grand:
you take 1 valence shell light exposure of Hydrogen
Time Gravity to Reduce = 1

Equation is balanced 1 = 1
but just as 1 = .999999999999999999999999^ ∞

Matter fissile's into a black hole conundrum and the Universe vanishes in .9999999999999999999^Light speed

Thus an equation out of the Big Bang: oh yes half credit Einstein and I will get 51-50 credit you cool with that 


G t ∝ mc²/e

Let me encode this for you if Skull and Bones loves Genesis 3:22 then they will get a kick out of Revelations 21:1

[zeebo]

"Discovery of a Thorne-Zytkow object candidate in the small magellanic cloud" ....

Damn those Thorne-Zytkow object candidates are always in the last place you look.

[Jackstar]

Here is my Rap song about

*blink* Parsing your posts as rap makes them all... well, it doesn't make them all make sense, but at least they're easier to dance to.

[area51drone]

Every thread on this forum has been invaded with insanity.   There's no hope for bellgab.  It is doomed.

[wr250]

Every thread on this forum has been invaded with insanity.   There's no hope for bellgab.  It is doomed.

this goes in the "bellgab is doomed" thread.

[Agent : Orange]

http://youtu.be/Z_QyGANCUJI