If you've commented anonymously on this site or thousands of others where you are not a registered member, you've come across the Completely Automated Public Turing Test to Tell Computers and Humans Apart (CAPTCHA) box - and maybe you dread it because, when it doesn't recognize the letters you think you are seeing, you are stuck.

Venu Govindaraju, a computer scientist at the University of Buffalo who pioneered machine recognition of human handwriting, says a 21st-century solution to CAPTCHA problems may rest in the early days of human culture - handwriting. 

It's known that water vapor and clouds are by far the major contributors to the 'greenhouse effect' on Earth but since those have had a predictable range the planet's temperature ultimately hinges on atmospheric levels of carbon dioxide, according to a new model by the Goddard Institute for Space Studies (GISS) in New York, which sought to analyze the nature of Earth's greenhouse effect and clarify the role that greenhouse gases and clouds play in absorbing outgoing infrared radiation. 

What happens when you think you have seen a recent collision between two asteroids but find a bizarre X-shaped object at the head of a comet-like trail of material?    You keep looking until you can figure it out.

In January, astronomers thought the new collision they found would have a debris field expanding rapidly, like shrapnel flying from a hand grenade, but when they watched the aftermath using Hubble, they found the opposite; the object was expanding very, very slowly and that it started, not a few days, but nearly a year before the January observations.

Chiquita Brands has announced that following years of intensive research and investment,  FreshRinse(TM) technology is ready to go.  

Yes, for those of you who can't be bothered to wash even your pre-packaged salad, this can be a real time saver.    Their claim; it dramatically reduces microorganisms on leafy greens and better maintains freshness.

They claim that FreshRinse(TM) is a scientifically validated advancement for fresh produce safety that delivers a substantial reduction in microorganisms on leafy greens, including superior microbial efficacy against such pathogens as Salmonella, Listeria monocytogenes and E. coli O157:H7, as compared to the industry's conventional chlorine sanitizers. 

How do astronomers weigh stars?    In most cases stars that are trillions of miles away can't be measured, though astronomers can get a best estimate using numerical models.

But in some instances a star could be measured using inference.    If the star has a transit planet, and that planet has a moon, and both of them cross in front of their star, the size and orbit can be measured to learn about the star.  Has it been done yet?   Well, no, since we have not found a star with both a planet and moon that transit but NASA's Kepler spacecraft should discover several such systems.

Two women who took part in the world's first controlled study of a genetic screening test before IVF have given birth to healthy babies.

The babies are the first deliveries in a pilot study of comparative genomic hybridization (CGH) by microarray, a new method of screening oocytes, female gametocytes involved in reproduction, before in vitro fertilization (IVF) for a full range of chromosomal disorders.