Starship Asterisk*

bystander wrote:Yes, the radiation probably should have been left off. the radiation is here, but the CMB is still there, but not 13.7 billion ly, more like 46.5 billion ly, the comoving distance to the edge of the observable universe.

bystander wrote:the radiation is here, but the CMB is still there, but not 13.7 billion ly, more like 46.5 billion ly, the comoving distance to the edge of the observable universe.

ronw12 wrote:Actually, the Microwave Background Radiation is NOT 13.7 billion light years distant. The radiation was captured by the Planck telescope. That means it is here. The radiation originated 13.7 billion years ago, but it can't be 13.7 billion years distant. We wouldn't be able to see it. This is kind of like saying when you take an image of the Andromeda Galaxy, M31, the light is 2.2 million light years distant. The galaxy is 2.2 million light years distant, but the light has to be in your telescope and in the CCD camera in order to see it.

Chris Peterson wrote:

Chuck Drinnan wrote:
I have what is probably a simple question. Why is this image elliptical?
What do the individual images look like that are mosaicked into this combined image?

The image shape is a consequence of the mapping used to display the celestial sphere on a flat screen. This is just like many mappings (e.g. Mercator) used to display the spherical Earth on a flat page. I don't think the image is actually a mosaic at all. The WMAP instrument basically looks at just one point of the sky. It is scanned to build up data covering the entire sky at a time. The raw dataset is probably just a big array of values associated with celestial coordinates. That data could be plotted many different ways- this is just one example.

http://en.wikipedia.org/wiki/Mollweide_projection wrote:
The Mollweide is a pseudocylindrical projection in which the equator is represented as a straight horizontal line perpendicular to a central meridian one-half its length. The other parallels compress near the poles, while the other meridians are equally spaced at the equator. The meridians at 90 degrees east and west form a perfect circle, and the whole earth is depicted in a proportional 2:1 ellipse. The proportion of the area of the ellipse between any given parallel and the equator is the same as the proportion of the area on the globe between that parallel and the equator, but at the expense of shape distortion, which is significant at the corners.

A Mollweide projection of the Earth

Click to view full size image

Also known as the Babinet projection, homolographic projection, or elliptical projection. As its more explicit name Mollweide equal area projection indicates, it sacrifices fidelity to angle and shape in favor of accurate depiction of area. It is used primarily where accurate representation of area takes precedence over shape, for instance small maps depicting global distributions.

• moll : minor (German)
  weide: meadow (German)

The projection was first published by mathematician and astronomer Karl Brandan Mollweide (1774 – 1825) of Leipzig in 1805 as an improvement upon the Mercator projection. It was popularized by Jacques Babinet in 1857, giving it the name homalographic projection.

Chris Peterson wrote:The WMAP instrument basically looks at just one point of the sky.

Chuck Drinnan wrote:I have what is probably a simple question. Why is this image elliptical? What do the individual images look like that are mosaicked into this combined image?

geckzilla wrote:
I think a lot of people feel betrayed to the point of animosity when they realize that space doesn't actually look like any of the cool photos on APOD most of the time. And by that I mean as seen with the naked eye. I can remember feeling that way a little but I learned fairly young and got over it quickly. It's just nice to have this fantasy vision of how it would be to fly around in a space ship through glowing nebulas and reality robs one of that fantasy unless you just completely ignore the facts. It's very enlightening to realize how limited human vision really is, though. I guess not everyone sees it that way.

• ________ Scientific American JUNE 1960
  
  "Putting a man in space is a stunt: the man can do no more
  than an instrument, in fact can do less." So said Vannevar Bush,
  chairman of the Board of Governors of the Massachusetts Institute of
  Technology, in a statement to the House Committee on Science and
  Astronautics. "ŒThere are far more serious things to do than to indulge
  in stunts. As yet the American people do not understand the
  distinctions, and we in this country are prone to rush, for a time, at
  any new thing. I do not discard completely the value of demonstrating
  to the world our skills. Nor do I undervalue the effect on morale of
  the spectacular. But the present hullabaloo on the propaganda aspects
  of the program leaves me entirely cool."

• -------------------------------
  ____ Up in the Air (2009)
  
  Natalie Keener (Anna Kendrick): So, what are you saving up for? Hawaii? South of France?
  
  Ryan Bingham (George Clooney): It's not like that. The miles are the goal.
  
  Natalie Keener: That's it? You're saving just to save?
  
  Ryan Bingham: Let's just say that I have a number in mind and I haven't hit it yet.
  
  Natalie Keener: That's a little abstract. What's the target?
  
  Ryan Bingham: I'd rather not...
  
  Natalie Keener: Is it a secret target?
  
  Ryan Bingham: It's ten million miles.
  
  Natalie Keener: Okay. Isn't ten million just a number?
  
  Ryan Bingham: Pi's just a number.
  
  Natalie Keener: Well, we all need a hobby.
  ____ No, I- I- I don't mean to belittle your collection. I get it. It sounds cool.
  
  Ryan Bingham: I'd be the seventh person to do it. More people have walked on the moon.
  
  Natalie Keener: Do they throw you a parade?
  
  Ryan Bingham: You get lifetime executive status. You get to meet the chief pilot, Maynard Finch.
  
  Natalie Keener: Wow.
  
  Ryan Bingham: And they put your name on the side of a plane.
  
  Natalie Keener: Men get such hardons from putting their names on things.
  ____ You guys don't grow up. It's like you need to pee on everything.
  -------------------------------

Chris Peterson wrote:Is it somehow unsatisfying, or intellectually dishonest? I don't think so. But I do get the sense that some people (none in this discussion!) have that concern with false color scientific images- even in cases like this where there is no alternative.

Chris Peterson wrote:

NoelC wrote:

orin stepanek wrote:False color: but it is quite pretty!

Uh oh, you realize that begs the question of what is a TRUE color microwave image... One you could cook with?

Well, you could try putting your head in a microwave oven, and maybe that would stimulate a color response. <g>

It's kind of like those recordings you hear of bat or dolphin sonar, where they mathematically lower the frequency so we can use our ears to get some sense of what these animals are hearing. Is that "false sound"? Is it somehow unsatisfying, or intellectually dishonest? I don't think so. But I do get the sense that some people (none in this discussion!) have that concern with false color scientific images- even in cases like this where there is no alternative.

jman wrote:Many recent discussions have surrounded the human sense of "sight" and the physiological perception of "colour". Because our eyesight is so imporant we put a very heavy emphasis on it's value. What if for a moment - we consider the eye just another sensor (stimulus-response), something akin to smell or taste or sound. In all reality, it's possible that sight is no less subjective than the sense of sound or taste or smell, and trying to describe what we "see" could be just as subjective (and futile) as trying to describe a smell. Look at how many words we have to describe the range of colours we can perceive - and compare this to the spectrum of sounds we can hear. There's really no difference technically.

NoelC wrote:

orin stepanek wrote:False color: but it is quite pretty! 8-)

Uh oh, you realize that begs the question of what is a TRUE color microwave image... One you could cook with? :D

orin stepanek wrote:False color: but it is quite pretty!

owlice wrote:This is one of my favorite APODs ever, simply for the sheer beauty and excitement of it;
it's just a piece of the image neufer posted above but deserves to be seen in all its glory!

Click to view full size image