Accurate targeting to the landing site is not expected to be a problem, but there are several opportunities to change the timing or course of reentry events if necessary.

Ensuring Accurate Targeting -- Fine-tuning of the trajectory leading up to the landing starts one month before the scheduled entry into Earth's atmosphere. From 30 days until one day prior to Earth entry, there are six opportunities to adjust the trajectory using the spacecraft's onboard thrusters. At about the distance of the Moon's orbit on May 1, 2004, Genesis will fly by the Earth and line up for its daytime landing in Utah.

The return capsule will be aligned to its proper entry orientation about six hours before entry. At that time it will be stabilized for flight into Earth's atmosphere by increasing its spin rate to approximately 15 rpm. The capsule will be released two hours later. (Navigation tracking requirements have been established to ensure accurate targeting of the capsule. Since the capsule does not have a propulsion system, there is no way to abort the entry sequence following its release. In the unlikely event that the capsule was not correctly targeted at this juncture, it would not be released.)

In the event of a problem that prevents these targeting and entry events from taking place, an option exists before the release of the capsule to make a course change that would place the entire vehicle into an elliptical orbit around the Earth of about 24 days' duration. This would be followed by a second entry attempt.

After the capsule is released, the main spacecraft will be diverted so it cannot collide with the sample return capsule. Having completed its mission of carrying the return capsule and its scientific cargo, the spacecraft will fire its large thrusters one last time in a "divert maneuver" that will deliver it into an orbit around the Sun, just ahead of the Earth.

Large Landing Footprint -- The landing site at the Utah Test and Training Range is a vast and unoccupied salt flat controlled by the U.S. Army and Air Force. The site was chosen because it provides an ample area to allow for aerodynamic uncertainties and winds that might affect the direction the capsule travels in the atmosphere. The landing footprint for the sample return capsule is about 30 by 84 kilometers (18 by 52 miles).

Will the solar matter Genesis is returning cause any concern about extraterrestrial materials?

The Genesis sample, consisting of protons and atoms from the Sun, does not pose any risk to the Earth. On the basis of recommendations from the National Research Council's Space Studies Board, the mission has been given a planetary protection designation of "unrestricted" Earth return. It is the board's determination that the sample has no potential for containing life.

Since this mission is named Genesis and will tell us about the beginning of the solar system, will it try to prove or disprove the Bible?

The Genesis mission will collect samples of the solar wind, material flowing outward from the Sun, and return these samples to Earth. Scientists will be able to compare the compositions of these samples with known compositions of the planets and help in the effort to understand how our solar system and its planets formed. It is not NASA's role to address theological questions or interpretations, and Genesis' investigation will be studied as a scientific question, not a theological one.