(AP) - These drawings were made by two second-grade students in the Eastman School in Concord, New Hampshire on Feb. 1, 1986. The top picture, by Erin Eville shows herself crying with the shuttle overhead. In the bottom picture, Alana Maloney remembers Christa McAuliffe, who was a teacher in Concord, New Hampshire. (AP Photo)

(AP) - Arlene Dressler, right, holds her 4-year-old daughter Beth Ellen during a memorial service for teacher Christa McAuliffe at St. John?s Church in Concord, New Hampshire, Jan. 30, 1986. McAuliffe was killed in the explosion of the space shuttle Challenger. (AP Photo/David Tenenbaum)

(AP) - Flowers, telegrams, photographs, and a model of the Challenger lie in a display case, Jan. 30, 1986 at the Concord, New Hampshire. High School in remembrance of Christa McAuliffe, a teacher at the school who was one of seven astronauts killed in the space shuttle Challenger explosion. (AP Photo/Peter A. Southwick)

(AP) - A young girl rubs her eyes during a memorial service for teacher Christa McAuliffe at St. John's the Evangelist Church in her hometown in Concord, New Hampshire, Jan. 29, 1986. More than 300 adults and children attended the service which included discussions of their feelings over McAuliffe's loss. (AP Photo/Peter Southwick)

(AP) - Japan's four major newspapers, including the Asahi Shimbun (lower left), devoted their front pages to the explosion of the space shuttle Challenger on Jan. 29, 1986 in Tokyo, that took place after lift off from the Kennedy Space Center in Florida. (AP Photo/Temma)

(AP) - The vertical stabilizer or tail section of the Space Shuttle Challenger is seen on its side in front of the Vehicle Assembly Building, April 9, 1986, Kennedy Space Center. The Challenger exploded shortly after liftoff on January 28th killing seven astronauts on board. (AP Photo/Bruce Weaver)

(AP) - Two unidentified spectators at the Kennedy Space Center react after they witnessed the explosion of the space shuttle Challenger, Jan. 28, 1986. The shuttle, which carried a crew of seven, exploded just moments after takeoff. (AP Photo)

(News) - The Space Shuttle Challenger explodes seconds after takeoff January 28 1986. Seven crew members perished in the explosion. (Reuters)

(AP) - Acting NASA Administrator Dr. William Graham, right, watches as the remains of one of the crew of the Space Shuttle Challenger is carried from a jet to awaiting hearses at Dover Air Force Base in Dover, Delaware, April 29, 1986. At Dover AFB, the remains are to be prepared for burial in accordance with the wishes on the individual families. (AP Photo/Gary Emeigh)

(AP) - Debris from the ill-fated flight 51-L is unloaded by from Coast Guard cutter Dallas, Feb. 1986. The explosion of the Space Shuttle Challenger on January 28 killed all seven crew members. (AP Photo)

(AP) - Part of the debris from the space shuttle Challenger is lowered to dockside at Port Canaveral, Fla., Feb. 1, 1986. The Challenger exploded moments after lift off on Jan. 28, killing all seven crew members. (AP Photo/NASA)

(AP) - As a memorial to the space shuttle challenger?s crew, crowds line the beach carrying flashlights in Cocoa, Florida, Jan. 31, 1986 for a seven minute remembrance of the astronauts who died on Tuesday. (AP Photo/Joe Skipper)

(AP) - Unidentified boy looks at a shrine set up in memory of Christa McAuliffe at St. John's Church in Concord, New Hampshire on Jan. 30, 1986 following a memorial service in her honor. McAuliffe was killed in the explosion of the space shuttle Challenger on Tuesday. (AP Photo/David Tenenbaum)

(AP) - Richard Greene adjusts a letter as he sets up a billboard outside a Concord, New Hampshire motel on Jan. 30, 1986. Teacher Christa McAuliffe, who taught at Concord High School, was a crewmember aboard the ill-fated Space Shuttle Challenger. (AP Photo/Peter Southwick)

(AP) - Kennedy Space Center workers enroute to Pad 39B were met by the sight of seven small American flags that mysteriously appeared along side the road, Jan. 30, 1986. Seven crew members were killed in the explosion of the Space Shuttle Challenger on Tuesday which was launched from Pad 39B. (AP Photo/Phil Sandlin)

(AP) - Students attend a children's mass at Our Lady of Lourdes Catholic Church in Melbourne, Florida on Jan. 30, 1986, in honor of the seven crew members killed in the explosion of the Space Shuttle Challenger. (AP Photo/Joe Skipper)

(AP) - Father Daniel Messier, right, dries the tears of Concord, New Hampshire, sixth grader Tanya Lee at a memorial service for teacher Christa McAuliffe at St. John?s Catholic Church in Concord, Wednesday, Jan. 29, 1986. McAuliffe died on in the explosion of the space shuttle Challenger. (AP Photo/Toby Talbot)

(AP) - Motorists en route to work Wednesday morning passed this sign in memory of the Space Shuttle Challenger which exploded short after liftoff on Jan. 28, 1986 killing the crew of seven. (AP Photo/Joe Skipper)

(AP) - The American flag in the press site at the Kennedy Space Center flies at half-mast at Kennedy Space Center, Florida, Jan. 28, 1986 after NASA officials ordered it lowered following the explosion of the Space Shuttle Challenger. NASA said the crew of seven aboard the craft died in the explosion. Launch pad B is shown under the flag. (AP Photo/Jim Cole)

(AP) - A strange plume of flame is seen on the right side of the rocket booster of the space shuttle Challenger seconds after launching, Jan. 28, 1986, before the explosion that destroyed the space shuttle, which carried a crew of seven. (AP Photo/NASA)

(AP) - This picture shows the breakup of the space shuttle Challenger January 28, 1986, 78 seconds after liftoff from the Kennedy Space Center. Top arrow shows the Orbiter's left wing. Center arrow shows the Orbiter's main engine; and the bottom arrow shows the Orbiter's forward fuselage. The picture was released June 9, 1986, in Washington, as part of the Presidential Commission on the space shuttle Challenger accident report. (AP Photo)

(AP) - The space shuttle challenger explodes 73 seconds after takeoff on Jan. 28, 1986, at Kennedy Space Center, Florida. This picture shows the main engine exhaust, solid rocket booster plume and an expanding ball of gas from the external tank, visible seconds after the space shuttle Challenger exploded. The seven crew members perished in the explosion. One of the shuttle's booster rockets, whose faulty O-rings were blamed for the disaster, shoots off to the right. (AP Photo/NASA)

(AP) - This photo shows a portion of the explosion of the Challenger space shuttle on Jan. 28, 1986 at Kennedy Space Center, Florida. The seven crew members perished in the explosion. One of the shuttle's booster rockets, whose faulty O-rings were blamed for the disaster, shoots off to the right. (AP Photo/NASA)

(AP) - President Ronald Reagan in the Oval Office after a televised address to the nation about the Challenger explosion on Jan. 28, 1986. He said: 'The crew of the space shuttle Challenger honored us by the manner in which they lived their lives. We will never forget them, nor the last time we saw them, this morning, as they prepared for their journey and waved goodbye and 'slipped the surly bonds of earth' to 'touch the face of God.' (AP Photo/Dennis Cook)

(AP) - The family of Christa McAuliffe, a teacher who was America's first civilian astronaut, react shortly after the liftoff of the Space Shuttle Challanger at the Kennedy Space Center, Tuesday, Jan. 28, 1986. Shown are Christa's sister, Betsy, front, and parents Grace and Ed Corrigan. (AP Photo/Jim Cole)

(AP) - The crew for the Space Shuttle Challenger Flight 51-L, leaves their quarters for the launch pad, Jan. 27, 1986 in Kennedy Space Center, Florida. Front to back the commander Francis Scobee, Mission Spl. Judy Resnick, Mission Spl. Ronald McNair, Payload Spl. Gregory Jarvis, Mission Spl. Ellison Onizuka, teacher Christa McAuliffe and pilot Michael Smith. (AP Photo/Steve Helber)