space shuttle is in orbit. We can call you when it's about
to fly over your hometown: Spaceweather
"When I stepped outside last night (Sept. 12), I
received a pleasant shock: intense
green auroras shining through the clouds," reports
Martin McKenna of Maghera, Northern Ireland. There was
no particular reason for the display: Solar activity is
low and Earth's magnetic field is quiet. Why the green?
It must be aurora
Have you ever heard of the
planet Hygea? It's listed in the 1850 Annual of
Scientific Discovery along with 17 other planets:
Courtesy Joe Pollock, Appalachian
State University. [full
In those days, large asteroids such as Hygea,
were widely deemed planets. They appeared so in textbooks
and scientific journals. Adding asteroids to the other
known planets, Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus and Neptune, gave a grand total of 18. Imagine
the mnemonic: "My Very Educated [insert ten adjectives
here] Mother Just Served Us Noodles."
asteroids were eventually demoted.
It was a long, drawn-out affair, marked by decades of
disagreement and confusion. (Sound familiar?) By 1900,
however, order was restored to the Solar System: the planet
count was down to eight.
then came Pluto...
the human eye, the tiny, scattered spots of sunspot group
909 are hardly impressive. But when viewed through a telescope
tuned to the red glow of solar hydrogen--wow. "The
area is so active with plage that the spots are literally
drowning in it," says Camaran
Ashraf of Claremont, California. He took this picture
The seething magnetic froth (that's what plage is) does
not signal an impending flare, just "a unique visual
and photographic opportunity." If you have a solar
telescope, take a look.