Making Ice Cream in a Time of Global Warming

I intended to go to a lecture on humor in the Catholic Church, but I must have had the wrong room number because I ended up in a lecture on Astronomy and Physics. It was given by an Irish sounding professor with flamin red hair who spoke excitedly and bounced around a lot with lots of energy:
Astronomers have found an enormous void in space that measures nearly a billion light-years across.

It is empty of both normal matter - such as galaxies and stars - and the mysterious "dark matter" that cannot be seen directly with telescopes.

The "hole" is located in the direction of the Eridanus constellation and has been identified in data from a survey of the sky made at radio wavelengths.

The discovery will be reported in a paper in the Astrophysical Journal.

Previous sky surveys that have traced the large-scale structure of the nearby Universe have long shown, for example, how the clustering of galaxies is strung into vast filaments and sheets that are separated by great gaps.

But the void discovered by a University of Minnesota team is about 1,000 times the volume of what would be expected in typical cosmic gaps.

"It's hard even for astronomers to picture how big these things are," conceded Minnesota's Professor Lawrence Rudnick.

"If you were to travel at the speed of light, it would take you several years to get to the nearest stars in our own Milky Way galaxy; but if you were to go to this hole and enter one side, you'd have to travel for a billion years before you would get to the other side," he told BBC News.

The void is roughly 6-10 billion light-years away and takes a sizeable chunk out of the visible Universe in its direction.

Dark evidence

The team used data from the US National Radio Astronomy Observatory's VLA Sky Survey (NVSS) to make its discovery. The VLA - which stands for Very Large Array - is a collection of 27 radio telescopes in New Mexico.

The finding is said to fit neatly with observations of the Universe's "oldest light" - the famous Cosmic Microwave Background (CMB) radiation, the study of which has earned several scientists the Nobel Prize.

This is the radiation that comes from just 380,000 years after the Big Bang when the Universe had cooled to such a degree that hydrogen atoms could exist. Before that time, scientists say, the Universe would have been so hot that matter and light would have been "coupled" - the cosmos would have been opaque.


THE CMB - OLD AND COLD
CMB (Rudnick et al., NRAO/AUI/NSF, NASA)
Nasa Probes have mapped the Cosmic Microwave Background which is all around us in space
This radiation from the infant Universe shines at weak radio (microwave) wavelengths
The maps show up tiny temperature fluctuations - the mottled colours above
These fluctuations correspond to the early distribution of matter in the fledgling cosmos
Nasa's WMap satellite sees a cold spot lying in the path of the newly found void

'Ancient light' takes Nobel
Today, this light shines at microwave wavelengths at a frigid -270C; and observations of the CMB made by Nasa's Wilkinson Microwave Anisotropy Probe show a particular "cold spot" in the direction of the newly identified void.

The explanation for this may lie in the enigmatic "dark energy" that scientists know so little about but which is said to be accelerating the expansion of the Universe.

Light particles passing through the void would be expected to lose a little more energy than those passing through space cluttered with matter - if dark energy is stretching the Universe apart at a faster and faster rate.

Scientists refer to this as the Integrated Sachs-Wolfe Effect and a corresponding "warm spot" in the CMB associated with an area of space dominated by a supercluster of galaxies was identified some years ago.

"In essence, this latest study gives us a very elegant demonstration of the existence of dark energy in a way which is very convincing," commented Professor Carlos Frenk, the director of the Institute for Computational Cosmology at Durham University, UK.

"We keep getting evidence for dark energy, this component of the Universe which is so dominant, and yet we still have only a tiny glimmer of what it could be."

The reason the void exists is not known. "That's going to be a challenge for people that work on the development of structure in the Universe. It's a very hot topic in the cosmology right now," said Professor Rudnick.
this space of nothing (reminds me of one of Stanislov
Lem's "Robot Tales" (trans to Eng as "The Cyberiad") where
a scientist creates a machine that can destroy anything
starting with (i think) the "letter" n. (plays MP sketch
on continuous repeat while dusts off maths part of me brain)..

So, let's see

1 billion (is that 10^9 - ie, US usage of "billion" or
10^12 ?)
regardless - assuming 10^9.... (notice those handy little decimal points!! ;)

Milky Way Gallaxy is about 30_000 LY's across (lenght-wise; pls ahem me if i'm wrong).

So, that works out to about 33_000 MW Galaxy's across.

The Earth (see map) is about 13_000 km across and is about 150M km from the sun,

So, we could stretch out a line of 11645 Earths from earth-orbit to the sun
and that space would STILL be THREE TIMES that large - relatively.

Or, The distance to the nearest star is 4-1/3 light years (Alpha Centauri - or is
that Barnard's star?) anyway,

(puts tounge in side of mouth and squinches up right eye,
raises left-eyebrow "Spock"-like)

300_000 km /sec * 31*10^7 secs / year gives 9.3 trillion (10^12) km/LY

So, Alpha centauri is about 40 Trillion km away

The solar system is about 10 AU (Astronomical units across - dist from earth to sun)

I think that works out to about 3300 SOLAR SYSTEMS from here to Alpha Centari
and this BIG NOTHINGNESS (Perhaps we should be calling it MISTER NOTHINGNESS?
Or are nothingnesses considered female? - nether?)
is STILL TEN TIMES that.

Now for the punch line:

If only we send a probe there - after all, with that much nothingness
(like the article sed) the physics would REALLY be ultra-FLAT space!
Just imagine being able to try to detect gravity waves there!

Or of course, prob those nasty real estate people would step in and the
next thing you'd know is there'd be a McDonalds on every other corner.