Announcement

Collapse
No announcement yet.

It's useless science Friday in my head - Welcome to the show.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Originally posted by slow99 View Post
    H2O occupies more volume in its solid state than liquid, correct?
    Right. "Occupied space" is basically density, and solid water is less dense than liquid water (which is why ice floats) but that is opposite of most other things - it's due to the rigid hexagonal structure of H2O when frozen, as compared to the fluid nature of the bonds at higher temps.

    It's also what permitted life to grow on Earth in the first place. If ice didn't float bodies of water would freeze bottom up instead of top down and aquatic life would not be able to survive being frozen solid.

    Comment


    • #32
      Originally posted by racrguy View Post
      Where do you find this stuff at?
      Mostly it's the fact that I tend to get lost down the rabbit hole when I read things. Books lead me to google - google leads me to blogs - blogs lead to articles - articles lead to wiki...

      Comment


      • #33
        Originally posted by Strychnine View Post
        Right. "Occupied space" is basically density, and solid water is less dense than liquid water (which is why ice floats) but that is opposite of most other things - it's due to the rigid hexagonal structure of H2O when frozen, as compared to the fluid nature of the bonds at higher temps.

        It's also what permitted life to grow on Earth in the first place. If ice didn't float bodies of water would freeze bottom up instead of top down and aquatic life would not be able to survive being frozen solid.
        Cool. I remembered learning that decades ago and it sparked a question for which I, admittedly, never sought an answer. I asked my 8th grade science teacher, but what good is that gonna do, lol.

        If solid water occupies more space than liquid, why do melting ice caps raise the sea level? It's probably an easy question for you, if you know please fill me in. If not, no biggie, don't waste time on it - I can do some Googling. Thx.
        Originally posted by davbrucas
        I want to like Slow99 since people I know say he's a good guy, but just about everything he posts is condescending and passive aggressive.

        Most people I talk to have nothing but good things to say about you, but you sure come across as a condescending prick. Do you have an inferiority complex you've attempted to overcome through overachievement? Or were you fondled as a child?

        You and slow99 should date. You both have passive aggressiveness down pat.

        Comment


        • #34
          Originally posted by slow99 View Post
          Cool. I remembered learning that decades ago and it sparked a question for which I, admittedly, never sought an answer. I asked my 8th grade science teacher, but what good is that gonna do, lol.

          If solid water occupies more space than liquid, why do melting ice caps raise the sea level? It's probably an easy question for you, if you know please fill me in. If not, no biggie, don't waste time on it - I can do some Googling. Thx.
          Doesn't the ice float on top of the water? It would put a lot of that frozen water on top of the liquid water and not factoring into the rise of the water level (except the ice submerged below the liquid's level).

          Comment


          • #35
            Because not all of the ice is under the surface of the water. DUUUHHH!

            (I really don't know the answer to that question)

            Comment


            • #36
              With ice, most of it is below the surface, like in a soda. The ice doesn't float on top, but mostly submerged until all of the forces balance. (I don't think buoyancy is the correct term since we're talking about a density difference)

              Comment


              • #37
                Originally posted by slow99 View Post
                Cool. I remembered learning that decades ago and it sparked a question for which I, admittedly, never sought an answer. I asked my 8th grade science teacher, but what good is that gonna do, lol.

                If solid water occupies more space than liquid, why do melting ice caps raise the sea level? It's probably an easy question for you, if you know please fill me in. If not, no biggie, don't waste time on it - I can do some Googling. Thx.
                In a perfect world melting ice in a body of water wouldn't change anything. Picture an iceberg. If you draw a free body diagram you see that the "weight" of the iceberg is exactly equal to the buoyant force holding it up (thanks Archimedes). Conservation of mass = melted iceberg fits in the space previously displaced by its weight.

                But the world is not ideal. The big issue is that glacial melting raises sea levels bc the ice was not initially supported by the sea, but by land - it's effectively runoff into the oceans.
                Last edited by Strychnine; 01-04-2014, 10:40 PM.

                Comment


                • #38
                  Originally posted by racrguy View Post
                  With ice, most of it is below the surface, like in a soda. The ice doesn't float on top, but mostly submerged until all of the forces balance. (I don't think buoyancy is the correct term since we're talking about a density difference)
                  Random fact: due to density differences of solid and liquid water every iceberg you see (or lone ice cube in a glass) will be just a tad more than 90% below the surface and slightly less than 10% above.

                  Comment


                  • #39
                    Originally posted by Strychnine View Post
                    The big issue is that glacial melting raises sea levels bc the ice was not initially supported by the sea, but by land - it's effectively runoff into the oceans.
                    Thanks. So, think about the (northern) polar ice cap as so extensively frozen, that it's akin to a continental land mass? If so, that makes sense.
                    Originally posted by davbrucas
                    I want to like Slow99 since people I know say he's a good guy, but just about everything he posts is condescending and passive aggressive.

                    Most people I talk to have nothing but good things to say about you, but you sure come across as a condescending prick. Do you have an inferiority complex you've attempted to overcome through overachievement? Or were you fondled as a child?

                    You and slow99 should date. You both have passive aggressiveness down pat.

                    Comment


                    • #40
                      Originally posted by slow99 View Post
                      Thanks. So, think about the (northern) polar ice cap as so extensively frozen, that it's akin to a continental land mass? If so, that makes sense.
                      The South Pole is a continental glacier, but the North Pole is a giant piece of ice.

                      Comment


                      • #41
                        Originally posted by racrguy View Post
                        The South Pole is a continental glacier, but the North Pole is a giant piece of ice.
                        Of course; that's why I clarified thinking about the north as akin to ...
                        Originally posted by davbrucas
                        I want to like Slow99 since people I know say he's a good guy, but just about everything he posts is condescending and passive aggressive.

                        Most people I talk to have nothing but good things to say about you, but you sure come across as a condescending prick. Do you have an inferiority complex you've attempted to overcome through overachievement? Or were you fondled as a child?

                        You and slow99 should date. You both have passive aggressiveness down pat.

                        Comment


                        • #42


                          Gemini's First Image Shows a Planet Orbiting a Star 63 Light Years Away

                          January 8, 2014

                          It might not be much to look at, but this image is insanely exciting. You're looking at the first ever image of a planet, orbiting a star, over 63 light years from Earth.

                          Acquired by the world's most powerful planet-hunting instrument, the Gemini Planet Imager, it shows a 10-million-year-old planet called Beta Pictorus orbiting its giant parent star. It's the first such image to come from Gemini, which has been under development for over a decade but is only now producing data like this.

                          The Imager detects infrared radiation to readily spot young planets, whose post-formation afterglow is in that part of the spectrum, while masking light emitted by parent stars that can often interfere with images. In fact, we've written in detail about how it works in the past, so you cango read about it in depth if, like us, space telescope engineering gets you hot under the collar.

                          Obviously, as well as being insanely cool, images like this will help researchers understand far-off planetary system more accurately than ever before. And the best news is that, in the future, you can expect a slew of such images: currently the team is analyzing 600 other young stars and the planets that surround them, [Gemini Observatory]

                          Figure 1. Gemini Planet Imager’s first light image of Beta Pictoris b, a planet orbiting the star Beta Pictoris. The star, Beta Pictoris, is blocked in this image by a mask so its light doesn’t interfere with the light of the planet. In addition to the image, GPI obtains a spectrum from every pixel element in the field of view to allow scientists to study the planet in great detail.

                          Beta Pictoris b is a giant planet – several times larger than Jupiter – and is approximately ten million years old. These near-infrared images (1.5-1.8 microns) show the planet glowing in infrared light from the heat released in its formation. The bright star Beta Pictoris is hidden behind a mask in the center of the image.


                          Gemini Planet Imager (GPI) was designed, built, and optimized for imaging faint planets next to bright stars and probing their atmospheres. It will also be a powerful tool for studying dusty, planet-forming disks around young stars. It is the most advanced such instrument to be deployed on the 8-meter Gemini South telescope in Chile.
                          Last edited by Strychnine; 01-08-2014, 01:52 PM.

                          Comment


                          • #43
                            Long story short - in 1979 the theory of cosmic inflation was introduced and part of it was the thought that this would leave behind evidence in the form of gravitational waves. The tech did not exist at the time to even begin searching for evidence supporting the theory though...

                            Until the BICEP2 experiment (left)








                            Big Bang's Smoking Gun Found

                            Mar 17, 2014 11:10 AM ET // by Irene Klotz



                            The detailed, all-sky picture of the infant universe created from nine years of WMAP data. This map represents the tiny temperature fluctuations (anisotropies) measured in the ancient cosmic microwave background radiation of the universe.


                            For the first time, scientists have found direct evidence of the expansion of the universe, a previously theoretical event that took place a fraction of a second after the Big Bang explosion nearly 14 billion years ago.

                            The clue is encoded in the primordial cosmic microwave background radiation that continues to spread through space to this day. Scientists found and measured a key polarization, or orientation, of the microwaves caused by gravitational waves, which are miniature ripples in the fabric of space.

                            Gravitational waves, proposed by Albert Einstein’s General Theory of Relativity nearly 100 years ago but never before proven, are believed to have originated in the Big Bang explosion and then been amplified by the universe’s inflation. “Detecting this signal is one of the most important goals in cosmology today,” lead researcher John Kovac, with the Harvard-Smithsonian Center for Astrophysics, said in a statement.

                            Because gravitational waves squeeze space as they travel, they imprint a specific pattern in the cosmic microwave background. Like light waves, gravitational waves have “handedness” that correlates to left- and right-skewed polarizations. Using a special telescope located at the South Pole, scientists not only detected gravitational waves in the universe’s fossil radiation; they also found that the telltale polarization signals are much stronger than expected.

                            “This has been like looking for a needle in a haystack, but instead we found a crowbar,” team co-leader Clem Pryke, with the University of Minnesota, said in a press release.

                            In addition to providing the first direct evidence of the universe’s inflation, the measurements can be used to date the process and determine how much energy it took.

                            Computer models indicate that the universe expanded by 100 trillion trillion times in .0000000000000000000000000000000001 (10 to the minus-34) seconds after the Big Bang explosion 13.8 billion years ago.

                            The telescope used to detect the gravitational waves is called Bicep, short for Background Imaging of Cosmic Extragalactic Polarization.

                            A press conference to discuss the findings is scheduled for noon today.




                            For the stats guys - the "data confidence" is 5.9 sigma.
                            5 sigma is required for a "discovery" which is about what they had when they announced the probable discovery of the Higgs Boson.

                            Comment


                            • #44
                              So this is evidence in favor of the gravity waves theory?

                              Comment


                              • #45
                                So, like, we are all surfers, like riding the gravity wave man.

                                Comment

                                Working...
                                X