Network executives must have a very low outlook on life. They keep thinking disaster is going to strike at any minute or God is going to wipe us off the face of the Earth in the blink of an eye.

Last month, the moon was being hurled toward our planet in the miserable made-for-TV movie "Impact." Now it's a meteor.

"Meteor," a two-part, four-hour NBC "miniseries" (remember when "miniseries" were actually miniseries that lasted at least four segments?), shares a lot in common with ABC's "Impact." Both have very big inanimate objects on a crash course with Earth. Both have scientists trying desperately to warn the government about the impending disaster. And both prove that very big special-effects movies are the domain of theaters, not TV. "Meteor" debuts Sunday, July 12, at 8 p.m. on KSL, Ch. 5. The second part airs next Sunday, July 19.

But "Meteor" is a better, more exciting epic than "Impact," which is like saying a meteor the size of Chicago is less destructive than a meteor the size of New York City.

Christopher Lloyd plays a less-manic scientist than he's known for (he was Doc Brown in the "Back to the Future" movies) who discovers that a comet has careened into a large asteroid, altering its normal course. The asteroid has now broken into two parts, and each is headed for Earth, setting off a worldwide panic and a lot of scenes of general stupidity.

For the next four hours, "Meteor" becomes nothing but a series of nonconnecting storylines, with ominous shots of hurling meteors for transitions.

In one story, an assistant scientist (Marla Sokoloff, from "The Practice") spends the entire movie trying to get to the Jet Propulsion Laboratory with information on how to stop the big meteor, but always seems to run into one obstacle or another.

In another completely unnecessary subplot, a serial killer (Michael Rooker) is on a rampage of vengeance while being chased by a detective (Billy Campbell, from "The Rocketeer"). How that has something to do with falling meteors is beyond my simple comprehension.

All of that culminates in a climax with one silly notion: Will a serial killer get in the way of saving humanity from total annihilation?

It's all B-grade science fiction stuffed into four hours. At least there are the occasional moments of action, which is more than "Impact" had in its banal, lifeless story.

So if you see a television executive on the street, remember to give him or her a hug today. I don't think we can tolerate any more negativity on TV.

Vince Horiuchi 's column appears Mondays and Fridays. He can be reached at vince@sltrib.com or 801-257-8607. For more television insights, visit Horiuchi's blog, "The Village Vidiot," at blogs.sltrib.com/tv/. Send comments about this column to livingeditor@sltrib.com.