Cosmic Cockroaches

August 31, 2007: Starved. Stomped. Radiated. Poisoned. It's all in a day's work for the common household cockroach. The abuse these creatures can withstand is amazing.

But astronomers have found something even tougher—"polycyclic aromatic hydrocarbons," says Achim Tappe of the Harvard Center for Astrophysics. "They can survive a supernova."

see captionPolycyclic aromatic hydrocarbons (PAHs for short) are ring-shaped molecules made of carbon and hydrogen. They're about as well loved as roaches: PAHs are a widespread organic pollutant, appearing in auto exhaust, oil spills and cigarette smoke. The EPA has classified seven PAH compounds as human carcinogens.
see caption
Right: A ball-and-stick model of the polycyclic aromatic hydrocarbon naphthalene, commonly found in mothballs.

But even PAHs have their virtues: Ring-shaped molecules similar to PAHs are found in DNA, and there's a growing consensus among biologists that PAHs were present on Earth 4.5 billion years ago when life began. By serving as building blocks for larger molecules of life, PAHs may have played an essential role in the chemical process of genesis.

That's why Tappe's recent discovery may be so important.


Powered by ScribeFire.


Digital Cameras Reveal Hidden Images

Kameraflage: context-sensitive display technology, encodes a layer of information that can only be viewed by the human eye when looking at an image of the scene taken by a camera.

Kameraflage is possible because digital cameras see a broader spectrum of light than human eyes. By rendering content in these wavelengths we are able to create displays that are invisible to the naked eye, yet can be seen when imaged with a digital camera."

In other words, you can now place hidden messages on print ads and billboards and t-shirts and other stuff that will only be visible to people when they take a picture of it with a digital camera or a camera phone.


Powered by ScribeFire.


Did Life Begin In Space? New Evidence From Comets

Recent probes inside comets show it is overwhelmingly
likely that life began in space, according to a new paper by Cardiff
University scientists.

Artist's impression of the Deep Impact comet probe. (Credit: NASA)

Professor Chandra Wickramasinghe
and colleagues at the University's Centre for Astrobiology have long
argued the case for panspermia - the theory that life began inside
comets and then spread to habitable planets across the galaxy. A recent
BBC Horizon documentary traced the development of the theory.

the team claims that findings from space probes sent to investigate
passing comets reveal how the first organisms could have formed.


Powered by ScribeFire.


Laser flips magnetic bit without any help

Physicists in Netherlands and Japan are the first to flip the value of a magnetic memory bit by firing a very short pulse of circularly-polarized laser light at it. Unlike other magneto-optic data storage systems, no external magnetic field was required to flip the bit, which meant that its value could be changed about 50 thousand times faster than the fastest conventional memory. The result could lead to the development of low-cost and ultrafast all-optical magnetic hard disk drives.

Writing data



The Human Piano

Here's a video from Force Theory Productions, an arty outfit who have invented the Human Piano, seen in the clip. I couldn't quite work it out, so I asked them what's going on. Michael wrote back: "The idea is that sound through wire is low level electricty. That electricity can easily pass through human bodies. It works by taking a source [in this case several iPods] and having the outputs go into a large copper pipe. Whatever sound is being played out of the ipod is now in the pipes. Then someone grabs firmly onto the pipe (as how hard you grab will effect conductivity and therefore loudness). The sound is now in the person. On the other side of it, I have a tight copper pinky ring that has a wire attached to it. The wire goes to a mixer and to the speakers. Once I grab someones hand, the sound goes:
iPod → Copper Bar → Human → Me → Mixer → Speaker
"Polyphony is just touching more than one source input at a time. The sound mixes inside me. The grand idea is to have a 16 person piano and play a piece just composed for the human piano in public at some point."