Life is Like the Tip of an Iceburg. There's More Hidden than Seen.


Xmas 2013 Comet May Outshine the Full Moon

A Typical Comet with Tail

Vitali Nevski and Artyom Novichonok, of the International Scientific Optical Network (ISON) in Russia, discovered comet C/2012 S1 (ISON) on 21 September 2012 via images taken with a 40-centimetre reflecting telescope. Other sky-watchers soon spotted it, and the International Astronomical Union’s Minor Planet Center in Cambridge, Massachusetts, announced the finding on the 24th of September.

(Image: E. Guido, G. Sostero, N. Howes)

Today, the newfound comet seen above is just a tiny dot in the sky beyond Jupiter. But in about a year, it might be one of the brightest objects in our night sky.

From the combined observations, astronomers were able to trace the comet’s recent path and find images of it dating back to late December 2011. From there they calculated a near-parabolic orbit that has comet ISON headed almost straight towards the sun.

Astronomers at the Remanzacco Observatory in Italy think that ISON will skim less than 1.4 million kilometres from the sun’s surface on 28 or 29 November.

The comet’s orbit also suggests it is a newcomer fresh from the Oort cloud, a distant halo of icy objects that surrounds the solar system. We last had a visitor direct from the cloud in 2009, when the green comet Lulin swooped in and sprouted two tails.

As with Lulin, the intense heat of ISON’s solar fly-by should vaporise the comet’s hard shell of pristine ices, releasing trapped dust that would help it grow an exceptionally bright tail. Astronomy Now magazine reports that comet ISON could even be brighter than the full moon around its closest approach to the sun.

Skirting our star means that, to viewers on Earth, the comet will appear close to the horizon and to the sun’s glare, making it difficult to see at first. ISON will fade but become easier to spot as it heads back towards the outer solar system. By 9 December it should be about as bright as Polaris, the North Star, according to Remanzacco Observatory astronomers. ISON should continue to be visible to the unaided eye until mid-January 2014.

But veteran astronomers warn that fresh comets with orbits that almost skim the sun are notoriously unpredictable. Results can range from the spectacular comet McNaught of January 2007 to the infamously fizzled comet Kohoutek of 1973.
(reprinted from New Scientist 21:57 25 September 2012)

Orbital position of Comet ISON on 11 December 2013 after perihelion

Comet ISON will come to perihelion (closest approach to the Sun) on 28 November 2013 at a distance of 0.012 AU (1,800,000 km; 1,100,000 mi) from the center point of the Sun. Accounting for the solar radius of 6.955×105 km, the comet will pass approximately 1,100,000 kilometres (680,000 mi) above the Sun’s surface. Its orbit is nearly parabolic, which suggests that it may be a new comet coming fresh from the Oort cloud. On closest approach, the comet will pass about 0.072 AU (10,800,000 km; 6,700,000 mi) from Mars on 1 October 2013, and it will pass about 0.42 AU (63,000,000 km; 39,000,000 mi) from Earth on 26 December 2013. Some of the orbital elements of comet ISON are similar to that of the Great Comet of 1680 which suggests the two comets may have fragmented from the same parent body.



Powerful Visual Illusions Shed Light on Brain Function

Preamble: Researchers at the University of Pennsylvania have calculated that the human eye can transfer data at the rate of approximately 8.75 megabits per second. Roughly 30% of neurons in the brain’s cortex are devoted to vision, compared with 8% for touch, and 2% for hearing. And, unlike other senses, human vision is processed in the back of the brain in a location called the occipital lobe. Senses of smell, taste, and hearing are processed in the sides of the brain in the temporal lobes.
Beau Lotto is founder of Lottolab, a hybrid art studio and science lab. With glowing, interactive sculpture and old-fashioned peer-reviewed research he’s illuminating the mysteries of the brain’s visual system.

He says context is everything because the light that falls onto your eyes is meaningless – it could be anything. Its what we do with that information that matters.

“Well then how do we see?”, He said.

“We see by learning to see. The brain evolved mechanisms for finding patterns and finding relationships in what we see and associating those relationships with behavioral meaning.”

Here is an example:

Do the top and bottom grey surfaces in the picture below appear different to you? Would it surprise you to learn they are both exactly the same shade of grey?

Are the Top and Bottom Surfaces the  Same shade of Grey?

Here is the same picture again with the area joining the top and bottom surfaces blacked out changing the context.

The lids now look the same.

The Shadow Information is  Blocked Out - Are They the Same Now?

Even though we know both surfaces are the same colour, the contextual information distorts our colour perception of the lower surface.

Here is Another Example:

In the picture below Beau is pointing to two coloured squares on a giant rubix square.

The top square appears to be dark brown while the lower square appears to be light brown or tan.

The rubix cube is evenly lit as can be seen by the light on his legs and arms. However, the front side squares are all dark colours to give the false appearance of being in the shade.

Beau then removes the lower brown square and places it next to the top brown square where we can see that the two squares are both the same colour.

Watch the square change colour in the following capured stills as he moves it up to the top square!

Now watch this fascinating TED talk by Beau Lotto to gain further insight into the way we see.

Beau Lotto: Optical illusions show how we see (16m)
Filmed Jul 2009 • Posted Oct 2009

I Want the LARGER Table!

In the picture below there are two tables in the children’s play room. One table appears longer and thinner than the other, but of course they are exactly the same!

When I first saw this picture I didn’t believe what I was seeing. No way did they look the same, no matter how I looked at it. I printed the image off in black and white and rotated it, trying to look at it from various angles with little success. So then I printed another copy and cut out the long thin tabletop and placed it over the other tabletop. And, hey presto, they were the same!

My brain was being totally fooled!

Pick On Someone Your OWN Size!

In this illusion the boy and girl are the same size and height yet because of the strong perspective lines going off into the distance the girl looks enormous whereas the boy appears tiny.

To our mind, the girl’s head is almost touching the ceiling and her arms can reach out for the walls, however the boy’s head is no where near the ceiling and his arms cannot stretch further than a square on the floor fooling us into believing the girl is a giant and the boy is a migit!

Noted lecturer, cognitive neuroscientist and skeptic, Al Seckel, takes great delight in perceptual illusions and the brain mechanics that they reveal. He is the author of many books, articles, and eye trick calendars. Since leaving Caltech in 2005 to pursue writing and his own research, he has continued his work in spatial imagery with psychology researchers at Harvard. He gave this TED talk in Feb 2004 (posted on the TED site in Apr 2007).

Al says we enjoy having our expectations violated and mostly what we perceive is based on past experience.

Watch this fascinating TED talk by Al Seckel.

Al Seckel: Powerful visual illusions (14m)
Filmed Feb 2004 • Posted Apr 2007

TED Talks – Beau Lotto – Optical Illusions Show How We See
Beau Lotto’s Lotto Lab
TED Talks – Al Seckel: Powerful visual illusions
Al Seckel’s Illusionworks
SBS – Test Your Brain You Won’t Believe Your Eyes
National Geographic – Test Your Brain
BBC – The science of optical illusions