There it was, just as promised, hanging in the southwestern sky: a point of light that didn't move as the stars and planets swung slowly across their nightly arc.
But the folks at the Maryland Science Center planned to take that "star" out of the heavens by the time Starlab opens to public viewings this weekend.
The unusual glowing object, seen during a demonstration last week, was actually a tiny puncture in the dome of a portable planetarium featured in "Starlab Weekend" at the Inner Harbor facility.
"We're kind of curious how the public will receive this," said Terry Nixon, supervisor of public programs at the science center.
Two Starlab domes of silver fabric, each 16 feet in diameter, 12 feet tall and accommodating 30 people at a time, will occupy the foyer outside the center's Davis Planetarium. Inside, the show "Seasonal Stars of Maryland" runs at 15-minute intervals beginning at 10:30 a.m. each day.
The permanent planetarium is closed for annual maintenance, and this is the first time the portable units -- usually seen by public school students as part of the center's traveling science programs -- will be tried in the main facility.
"We call them big silver igloos," said Mr. Nixon of the Starlab
units, each costing more than $10,000.
Ordinary house fans inflate the units, which viewers enter by stooping or crawling through a flexible entrance tube. Inside, they sit in two rows on squares of carpet, while young presenters -- either Nicole Hord or Brian Kortman -- tend a halogen-lamp projector at center and narrate the celestial show.
"You can't do all the fancy stuff a normal planetarium can do, but as a learning tool it's excellent," said Mr. Nixon.
A cylinder about 1 foot tall fits over the projector lamp, and can be angled to duplicate the Earth's axis for any date and time. Patterns of holes on the rotating cylinder allow light to shine through, thus projecting stars and planets on the dome.
In a recent demonstration, attended by a group of kids and adults rounded up from the day's Science Center visitors, Ms. Hord told about how ancient civilizations used the stars as their nightly entertainment.
With a light pointer, she sketched out the W-shaped constellation Cassiopeia, and retold the myth of the queen whose vanity caused her to be imprisoned in the sky, lying inverted on her throne.
"Of course, you really, really have to be able to use your imagination to see it," she noted.
She also stressed that many urban residents cannot see the stars as clearly as our ancestors because of light pollution from streetlights, headlights, neon signs and all the other illumination of modern life.
She began the show with a light level duplicating an average Baltimore night. Relatively few stars could be discerned, principally the northern array that forms the Big Dipper, Polaris the North Star, and the trio of Deneb, Altair and Vega that make up the Summer Triangle.
"Now I'll show you what you could see without the light pollution," she said.
The dome soon twinkled with several thousand points of light, as Ms. Hord sketched out a variety of constellations whose anchor stars could now be clearly seen.
"Especially in the city, many people have never seen the night sky this way," said Mr. Nixon.
After this weekend, the Starlab domes will resume their usual role, with some 80,000 public school students across the state -- usually in grades three through six -- scheduled to get a star show through the school year.
The Science Center this year is operating its Traveling Science Program statewide, under a $100,000 grant from the state Department of Education.
Where: Maryland Science Center, Inner Harbor
When: Every 15 minutes, beginning at 10:30 a.m., today and tomorrow. Science Center hours: 10 a.m. to 6 p.m.
Admission: Free with Science Center admission; $8.50 adults; $6.50 children 4-17, senior citizens and military; children 3 and younger, free
Call: (410) 685-5225