Architect Todd Schliemann covers all the angles while shedding light with his Japanese-inspired addition to the New York Hall of Science

In Flushing Meadows-Corona Park, that quaint future has been preserved and refurbished. A pair of space age rockets, freshly polished and newly installed, stands at attention outside the New York Hall of Science, noses pointed toward the stratosphere.

But verticality has lost some of its cachet. The moon conquest is old news, President George W. Bush's proposal to send a team to Mars was met with muted enthusiasm, and the future feels as though it is best approached aslant.

Accordingly, the newest extension of the hands-on teaching museum, a 55,000-square- foot exhibition hall designed by Todd Schliemann of Polshek Partnership Architects that opens Thursday, shoots off at all sorts of angles. The roof line dips, the walls lean, the ceiling folds and staircases whirl and curve. Seen through the window at the glass-tipped end of the wing, it's the rockets that look wrong, their cockeyed uprightness at odds with the building's judicious tilt.

Schliemann also designed the Rose Center for Earth and Space, the great, luminous, toylike ball-in-a-box at the American Museum of Natural History, and the Hall of Science evidently fired the same playful instincts. But where the Rose Center amplified the most fundamental geometries to the point where they began to look cosmic, this new, much smaller structure is about the play between the obvious and the illusory.

Like a magician's palm, Schliemann's surfaces hide nothing but still fool the eye. Made of Kalwall, a synthetic wool sandwiched between thin fiberglass boards, the walls and roof are stiff but seem no more substantial than a flimsy window shade. They let in the same buttery kind of all-over light, making the room feel simultaneously cozy and spacious. At night, when the indoor lamps come on, the low-slung slab becomes a beacon, potentially attracting the notice of a passing airliner with its skyward strip of brightness.

Like '60s science fiction

If the building is a body, the Kalwall is an insulated, translucent skin. Inside, the skeleton is laid bare - a set of slender steel ribs held together by ligaments of cable. Every working part is out in the open, and every component has a personality. Air flows in, not through hidden vents, but through breathing steel pillars with circular grilles that give them a resemblance to robot faces out of a 1960s science-fiction movie.

But those seemingly self-explanatory walls don't behave the way walls are supposed to behave. Each one is taller at one end than at the other, for example, and they slope in opposite directions, discombobulating one's sense of perspective.

To a person standing at one end of the hall, one side looks longer than it is, receding into an impossible distance, while the other appears unnaturally short. To bridge this jaunty symmetry, the roof divides into two tilted triangular planes, joined by a long diagonal beam that doesn't look level, but is. Oh, yes, and the walls tilt out.

Words make it all sound more complicated than it is: I demonstrated the structure to my 7-year-old son at a restaurant table by folding paper napkins. Indeed, the new wing has the clever, sturdy delicacy of origami, an impression reinforced by the rice-papery appearance of the ceiling and walls.

How serendipitous that the opening of this Japanese-inspired addition by a local architect should come just two days after the inauguration of the new Museum of Modern Art, designed by the Japanese architect Yoshio Taniguchi to harmonize with the corporate modernism of midtown Manhattan. The Tokyo-New York feedback loop hums.

So does the conversation with history. Schliemann's feather-light wing branches off from the 1964 original by Wallace K. Harrison, a windowless octagon dug out of the ground and supported by a massive central pillar. The plan recalls the octagonal chapter house of the Gothic cathedral in Wells, England, a light-suffused room, in the center of which a thick column gathers slender vaults into a stone bouquet.

But while the architects of the chapter house treated sunshine as rays of revelation, Harrison's concrete folly made a virtue of paranoia, since the exhibit hall at least appeared brawny enough to survive a Russian ICBM.

Above this dungeon filled with merry children and exhibits that click and whirr rises Harrison's cathedral, one of the most breathtaking interiors in New York. From outside, the undulating concrete form looks fortress-like and bleak, but walk into the Great Hall on a sunny day and with the electric lights off, and you find yourself in a huge, blackened shaft studded with glimmering glass stained a dozen shades of blue: royal, midnight, lapis, azure, aqua, and so on. Nothing supports the walls except their own corrugation, which makes darkness itself feel structural.

Expressive engineering

In the new extension, Schliemann has rejected Harrison's heaviness, but he has embraced his predecessor's concerns with expressive engineering and glowing walls. He answers the bunker's bulk with papery weightlessness, and matches the nocturnal majesty of the Great Hall with a cocoon awash in light. True contextual architecture has nothing to do with dogged imitation, but depends on freedom grounded in analysis.

It's never easy to know what children feel about an environment they spend the afternoon abusing, but they cannot miss the more obviously seductive details like the saffron-painted walls or the railings made from bent sheets of Swiss-cheese steel with holes just big enough to poke a finger through or let a ray of sunshine throw polka dots on the floor.

And if the New York Hall of Science sold a model kit for building a tabletop version of the new wing out of onionskin, wooden straws and rubber bands, kids could absorb fine architecture through their fingertips.