Science fact thread

I should probably stress for the sake of my American cousins that I'm not the seller. I also don't personally know the queen.
 
NeonKnight said:
I've heard rumors about planets in the "Goldilocks" ranges. (perhaps lots of them)
Click to expand...

That's been out in the public domain a while now though eh? All those experts are (having looked into it) solar system people.

Also (boooooo)

Update: According to Alexis Madrigal, the answer to the hyperbolic question in the headline is "no".

I'm sad to quell some of the @kottke-induced excitement about possible extraterrestrial life. I've seen the Science paper. It's not that
Click to expand...
 
NeonKnight said:
That said, are you really just dismissing the idea since the writer was likely out of his depth on concepts?
Click to expand...

I'm not totally dismissing the idea... mostly, I'm dismissing the article... and I'm holding the scientists at arm's length, with all that futzing they did with their work, it almost sounds like they massaged it until it gave them the results they wanted. Bad science, that.
 
Steven L Jordan said:
Originally Posted by NeonKnight View Post
That said, are you really just dismissing the idea since the writer was likely out of his depth on concepts?
Click to expand...

I'm not totally dismissing the idea... mostly, I'm dismissing the article... and I'm holding the scientists at arm's length, with all that futzing they did with their work, it almost sounds like they massaged it until it gave them the results they wanted. Bad science, that.
Click to expand...

You may well be correct to hold the science at arm's length.

But which is more likely? That Marioni and Buzzi massaged the science to get the results they wanted? (especially when it appears as if they were expecting spherical results.)

Or that the BBC writer is guilty of bad writing?

(I realize it's possible both scenarios are correct.)

Perhaps another perspective would help?

http://arstechnica.com/science/news...ergy-revealed-by-geometry-of-galaxy-pairs.ars

In this study, Marioni and Buzzi found that the symmetry in the distribution of binary galaxy pairs is broken if you use the wrong cosmological model, or if you get galaxy dynamics wrong. If the effects of the galaxy dynamics is understood, then it's possible to choose the correct cosmological model. The distance to faraway objects in our Universe can be measured with some accuracy using Hubble's law, which states that the recession speed of galaxies is proportional to the distance. Hubble's distance law relies upon the velocity of the galaxies (which is measured via the Doppler shift or redshift of the galaxies' light), but galaxies which are in a dynamic binary system will have an additional velocity component from their interactions that will insert errors into the Hubble law. Remove this effect via statistics, and the correct cosmological model can be found.

In order to apply this technique, binary galaxy pairs were selected from two archival astronomical surveys (721 galaxies from the Sloan Digital Sky Survey at a redshift of 0 and another 509 galaxies from DEEP2 survey at a redshift of up to 1.45). Working under the hypothesis that galaxy binaries truly are randomly distributed in orientation and that the distortions caused by the dynamic binary system can be calibrated from local observations of galaxies, Marioni and Buzzi found the data were perfectly consistent with previous cosmological models: the Universe is spatially flat and expanding via dark energy.
Click to expand...
 
NeonKnight said:
Perhaps another perspective would help?
Click to expand...

Much better... though it still sounds like there is a fair bit of guesswork involved, saying that flat space and dark energy fits the model, without having evidence of the actual effects of dark energy. But maybe I'm just nit-picking.
 
In all the reading I've ever done where the word 'dark' crops in in astrophysics it has always seemed synonymous with a deferred problem. This is (to my laymans mind) a language abstraction to a hole in the maths. Nobody but the top maths people (math for my American friends) are explaining the maths to one another, and the media remain hungry. Wild misinterpretations of the current scope of the mathematical landscape, followed by media hyperbole, followed by layman interpretation, followed by discussion of same seems pretty redundant given that they fairly clearly "just don't know yet".

:)
 
"There is no dark side of the moon. It's all dark really."

If you have a subscription to Nature, and you are a real rocket scientist, you can decipher all the "maths" futzed with by Marioni and Buzzi:

http://www.nature.com/nature/journal/v468/n7323/full/nature09577.html

Some geometry:

http://www.nature.com/nature/journal/v468/n7323/fig_tab/nature09577_ft.html

Perhaps they fried their numbers so that their "pancake universe" would match the results of NASA's WMAP spacecraft?

http://map.gsfc.nasa.gov/universe/uni_shape.html

The simplest version of the inflationary theory, an extension of the Big Bang theory, predicts that the density of the universe is very close to the critical density, and that the geometry of the universe is flat, like a sheet of paper. That is the result confirmed by the WMAP science.
Click to expand...
 
If they are going to be announcing they've found a new kind of arsenic-based life in Mono Lake, is that really an example of astrobiology?

That would seem kind of anti-climatic to me, we already know there is life at deep sea ocean vents that does not need sunlight. We also know there are bacteria that live quite happily deep within the Earth. So life as we don't know it, has already been known about for quite some time.

On the other hand, if they reveal something like chemical signatures that indicate "life" on Titan, well that would be a very important primary example of astrobiology or exobiology. There may be no limits to the implications for what this means for life in the universe.

I'm of the opinion that Ian M. Banks was really on to something in The Algebraist, that even gas giant planets like Jupiter could be the home of something beyond our imagining. (The Dwellers are a fantastic imagining of intelligent gas giant life.)

Even some mediocre SF like The Saga of the Seven Suns features star-based and gas-giant life. Robert Forward wrote a good book about solar-based life as well.

I'm pretty sure our own galaxy will have examples of "life" that are far far beyond the imagining of even our most creative SF visionaries.
 
NeonKnight said:
If they are going to be announcing they've found a new kind of arsenic-based life in Mono Lake, is that really an example of astrobiology?

That would seem kind of anti-climatic to me, we already know there is life at deep sea ocean vents that does not need sunlight. We also know there are bacteria that live quite happily deep within the Earth. So life as we don't know it, has already been known about for quite some time.

On the other hand, if they reveal something like chemical signatures that indicate "life" on Titan, well that would be a very important primary example of astrobiology or exobiology. There may be no limits to the implications for what this means for life in the universe.

I'm of the opinion that Ian M. Banks was really on to something in The Algebraist, that even gas giant planets like Jupiter could be the home of something beyond our imagining. (The Dwellers are a fantastic imagining of intelligent gas giant life.)

Even some mediocre SF like The Saga of the Seven Suns features star-based and gas-giant life. Robert Forward wrote a good book about solar-based life as well.

I'm pretty sure our own galaxy will have examples of "life" that are far far beyond the imagining of even our most creative SF visionaries.
Click to expand...


...and yet where is all their radiation?

so weird....
 
NeonKnight said:
I'm pretty sure our own galaxy will have examples of "life" that are far far beyond the imagining of even our most creative SF visionaries.
Click to expand...



The opposite of that is we ought to expect that life in the universe is almost nonexistent.
 
Sparrow said:
The opposite of that is we ought to expect that life in the universe is almost nonexistent.
Click to expand...

Why would we expect that? When you have only one data point, that being the Earth, extraoplations from it is fantasy not true science. As of this minute we have no way of knowing if life is rare, common or utterly unique. No matter what we believe what is needed is more data.
 
Sparrow said:
The opposite of that is we ought to expect that life in the universe is almost nonexistent.
Click to expand...

Yeah, not quite seeing where you're coming from, given the announcement today.

The revelation was a little bit anti-climatic, but exactly why should we think that life in the universe in nearly non-existent?

We've now found life at mid-ocean vents, bacteria buried deep within the Earth's mantle, and now microbes that can actually use arsenic, replacing phosphorus, as one of the essential building blocks of life.

"We know that some microbes can breathe arsenic, but what we've found is a microbe doing something new -- building parts of itself out of arsenic," said Felisa Wolfe-Simon, a NASA Astrobiology Research Fellow in residence at the U.S. Geological Survey in Menlo Park, Calif., and the research team's lead scientist. "If something here on Earth can do something so unexpected, what else can life do that we haven't seen yet?"
Click to expand...

http://www.nasa.gov/topics/universe/features/astrobiology_toxic_chemical.html

This implies that life can exist in all types of environments, not just those that contain oxygen and h20. Many more then we've even thought of before now.
 
mylinar said:
Why would we expect that? When you have only one data point, that being the Earth, extraoplations from it is fantasy not true science. As of this minute we have no way of knowing if life is rare, common or utterly unique. No matter what we believe what is needed is more data.
Click to expand...


Because I'm using science and just plain playing the odds... using the Drake Equation.

Verschuur presented his take on the Drake equation, formulated by astronomer Frank Drake in 1960, that provides a means for calculating the number of intelligent civilizations that it is possible for humans to make contact with.

The equation relates those chances to the rate of star and habitable planet formation. It includes the rate at which life arises on such planets and develops intelligence, technology, and interplanetary communication skills. Finally, it factors in the lifetime of such a civilization.

Using Drake’s equation, Verschuur calculated there may be just one other technological civilization capable of communicating with humans in the whole group of galaxies that include our Milky Way — a vanishingly small number that may explain why 30 years of scanning the skies for signs of intelligent life has come up empty.

“I’m not very optimistic,” Verschuur said.
Click to expand...



I think once you realize that humanity will someday be extinct, as all life on this planet will become no more, then you can better appreciate the mounting odds against life in the universe. Leastwise life that is capable of communicating with us through the dead of space.
 
You must log in or register to reply here.

Sponsors


We try to keep the forum as free of ads as possible, please consider supporting SFFWorld on Patreon


Your ad here.
Back
Top