In only 12 years, America built a program that won the race to the moon. But that was long ago. Ever since, NASA has been making do with an aging fleet of space shuttles, an international space station that might never be finished and unmanned probes telling us that Pluto isn't really a planet.

These two books give a glimpse why we have come so little after we went so far.

		"TOO FAR FROM HOME" By Chris Jones Doubleday ($24.95) "CHALLENGER REVEALED" By Richard C. Cook Thuinder's Mouth Press ($28.95)

To be fair, there is no space race today, so the will and money that made NASA so successful are gone. What remains, however, is an agency that is bigger but no longer as competent.

Jones' book is the more engaging of the two, but he's guilty of padding it. He wrote an award-wining article for Esquire on how American astronauts Donald Pettit and Kenneth Bowersox and Russian engineer Nikolai Budarin were stranded on the International Space Station after their ride home -- the shuttle Columbia -- exploded on re-entry Feb. 1, 2003. With the remaining shuttles grounded, there seemed to be no way to retrieve them. (They eventually returned aboard a Russian space capsule.)

Jones stretches a few points too far; for instance, he devotes two entire pages to what would happen to an astronaut's anatomy if he ripped his space suit while working outside the station. All you really need is one sentence to know that a tear in space is certain death.

Plus the book's ending: The story of how the trio of astronauts was nearly crushed to death by gravitational forces during their re-entry is dragged on and on.

Cook, on the other hand, has a harder task -- trying to prove that the Reagan White House pressured NASA into launching the Challenger in bad weather so that Reagan, while giving his State of the Union address, could call the shuttle and talk to Christa McAuliffe, the "teacher in space."

This plan is something he discovered while doing his own investigation into the tragedy. The book is subtitled "An Insider's Account of How the Reagan Administration Caused the Greatest Tragedy of the Space Age."

A NASA budget analyst, Cook spoke with engineers who believed problems with the shuttle could lead to an explosion. A launch in temperatures under 53 degrees was discouraged, but on Jan. 28, 1986, the day the Challenger began its fatal voyage, it was coated with ice.

Cook wrote a memo in July 1985 to his bosses about those concerns. When he believed that both NASA and a presidential commission investigating the accident were not serious about finding the truth, he leaked his memo to The New York Times. The leak spurred greater scrutiny of the event, and cold weather was identified as the cause.

Cook frequently quotes from engineering reports and commission transcripts to get his point across that NASA could have avoided the loss of seven astronauts.

These passages read like assembly directions for computers; a reader can only take so many step-by-step technical explanations.

When Cook writes about leaking the memo to The Times, his appearance before the commission, and his own investigation, his prose and story come alive, but only briefly before his story again becomes plodding.

At first, Cook thought the pressure to launch came from the military, but began to believe that the White House wanted the Jan. 28 launch in time for Reagan's address. He doesn't have proof, only circumstantial evidence that is intriguing.

For instance, Nancy Reagan consulted astrologers about the timing of her husband's actions. Cook quotes one of her astrologers who said he told the Reagans that Jan. 28 was not a good time for the shuttle to fly, but, as Cook reiterates, the president wanted his phone call to McAuliffe.

Both of these books are flawed, but if you want to see how far we've fallen from the glory days of landing on the moon, they will show you how it happened.