News flash: TV executives do pay attention.

Sure, they're usually a little slow on the up-take, but eventually, they notice.

Such is the case with the wave of new science fiction series about to land on our television screens.

After a period over the last couple of years in which they generally turned their noses at science fiction in favor of reality TV, medical shows, and such, the broadcast networks have rediscovered that there may be a mainstream audience for scifi after all.

Each of the Big Three -- ABC, CBS, and NBC -- each are preparing to debut their own version of an alien-invasion story. ABC has the most obviously named entry, with its series "Invasion," CBS has its series, "Threshold," and NBC has "Surface."

"Threshold" debuts Friday at 9 p.m. ET/PT, while the other two premiere next week.

Clearly, each of these new series owe their existence to the success of ABC's airline disaster hit, "Lost," but there's also more than that, as well.

In its first season, "Lost" has been only marginally a genre show, which focuses on the drama of marooned crash survivors living together on a tropical island. Its scifi or fantasy elements only have been hinted at.

The new series, by contrast, are a lot more upfront about their science fiction roots.

In the case of "Invasion," the name itself tells us pretty clearly what's going to unfold, and viewers of "Surface" apparently will get to see its supernatural creature up-close and personal in short order, in the form of a computer-generated character. "Threshold" also plainly revolves around science fiction, where its characters have to deal with an alien situation, "X-Files" style.

So where "Lost" merely dips its toes into scifi, these other series jump right in.

That each of the broadcast networks have been willing to buy series that take their genre concepts so much further, owes itself not only to "Lost," but to both the burgeoning success of "Battlestar Galactica" as well as current world events.

An unabashed space opera on a cable outlet, "Battlestar" has managed nonetheless to gather a huge audience for a cable series. That fact can't have escaped the attention of the powers that run the broadcast networks.

They figure, I think, that if a space opera on a cable channel can get so much audience attention, a more-accessible Earth-bound series with a scifi plot can get even bigger numbers.

Of course, I hope they are right. The chances all three of the new series will succeed are slim. But even if one or two of them click with audiences and find permanent homes on their networks' schedules, it will bode well for the future of science fiction on broadcast.

The series also owe another debt to "Battlestar."

Ron Moore's series has clearly struck a chord with viewers who see the cylons as stand-ins for terrorists.

These new series, likewise, are tapping into the zeitgeist in which space aliens are a handy, easy allegory to the shadowy, unpredictable threat of terrorism that we face every day in the real world.

It's just the mood of the times, I suppose.

I just long for the day when broadcast executives think we in the TV audience are ready once again for series about aliens as bumpy-headed friends and not only as a dark, mysterious menace.

A former entertainment journalist, Scott Nance is a member of the USS Chesapeake, an independent science-fiction and Star Trek club in the Washington, D.C., area. He is a columnist for Airlock Alpha, and can be reached at scottnance@airlockalpha.com.