It disappeared sometime Wednesday.

It reappeared sometime Thursday.

The 9-foot-tall monolith -- a replica of the mysterious icon central to the movie "2001: A Space Odyssey" -- has cropped up again in another Seattle park, this time on an island in Green Lake.

Cyberspace Tips

No one has claimed responsibility for the monolith, but news organizations received this e-mail shortly after 4 a.m. Thursday:

The area is green,
and a circle for all.
The center is where,
the monolith will next fall.

The monolith first appeared mysteriously with the dawn of 2001 in Magnuson Park on Tuesday.

Dozens of people went to the site Wednesday hoping to see the monolith, which was made of steel and measured about 9 feet tall, 4 feet wide and 1 foot thick.

But all that remained were a few puddles of wax -- apparently candles were lighted at the scene overnight -- and a red rose resting on the cement base that had held the piece.

'Some People' Act

No one has taken credit or responsibility for the vanishing monolith.

Originators of a possibly connected Web site -- www.supporthemonolith.org -- could be involved. The site features a doctored copy of the famed WWII photograph of soldiers raising the flag at Iwo Jima. In this version, they're placing a monolith.

Recalling the "2001" movie, in which monoliths from outer space somehow trigger evolutionary advances, the site's authors note that aliens have made no such deliveries lately.

"Rather than let these facts discourage us," the Web site says, "Some people have taken matters into their own hands."