Marvin Appel , co-editor of Gerald Appel's Systems and Forecasts, also sees reason for caution after the huge advance--but he's still bullish.

FORBES: Magazine Article

Kenneth Reid, editor of Spear's Security Industry Analyst recommends buying shares of OSI Systems , the Hawthorne, Calif.

FORBES: OSI Systems: X-Ray Payday

Simon Calder, travel editor of The Independent, says it's hardly surprising when you consider that there are different grading systems in England, Scotland and Wales.

BBC: Stars before your eyes

Science editor Alan Boyle's blog: NASA's top expert on near-Earth objects says that new telescope systems are gradually getting a handle on potentially threatening asteroids.

MSN: Big sunspot unleashes an intense solar flare