TV REVIEW : ‘Venus Unveiled’ an Engaging Portrait

Mona Lisa in a ponytail? A walking, talking work of art?

Well, it turns out that even if Venus did wear blue jeans--as Jimmy Clanton so adolescently offered in his 1962 hit song--it would not be nearly so strange as what space scientists are discovering about Earth’s “twin” planet.

In its engaging “Venus Unveiled” tonight, “Nova” and its own British twin, “Horizon,” reveal a portrait of a tortured, poisonous planet so unlike our own that many researchers are more confused than ever about this second-closest orbiting body to the sun.

“In the 1950s, I said Venus might be more promising to colonize than Mars,” British astronomer Patrick Moore says. “How wrong I was. If you go to Venus, you’ll be promptly fried, poisoned, squashed and cremated.”

Moore and others now know this primarily because of the Jet Propulsion Laboratory’s Magellan spacecraft, which completed a four-year mission to study Venus before running out of steam and plunging into the planet’s aforementioned inhospitable atmosphere one year ago. Before its demise, Magellan sent back enough radar data to allow JPL scientists in Pasadena to map Venus’ surface, which is not visible from above the lethal blanket of sulfuric acid clouds that swaddle the planet.

Magellan’s success--and JPL’s vivid computer re-creation of the Venusian surface--have left observers with a mystery they may never solve.

All bodies that we know of--including Earth--are pocked by collisions with random meteorites. Volcanic eruptions and other geologic phenomena periodically “repave” different regions, covering existing craters. By examining the distribution of craters, scientists can calculate the relative age of each part of a planet.

But Magellan revealed that Venus’ craters are uniformly distributed, meaning its entire surface is exactly the same age--and effectively dead. But with no active volcanoes or earthquake faults, how does the planet relieve itself--as it must--of its tremendous heat (900 degrees Fahrenheit) and pressure buildup?

There are two competing theories--both equally plausible and equally outrageous. Concludes Magellan deputy project scientist Ellen Stofan: “This is really confusing.”

Yes, but fun.

* “Venus Unveiled” airs on “Nova” at 8 tonight on KCET-TV Channel 28. It also airs at 8 p.m. Wednesday on KOCE-TV Channel 50.