Fifty years after humans first set foot on the moon, new scientific discoveries are fueling excitement for a return to the lunar surface -- this time, perhaps, to stay. Join the scientists and engineers working to make life on the moon a reality.

Fifty years after humans first set foot on the moon, new scientific discoveries are fueling excitement for a return to the lunar surface -- this time, perhaps, to stay. Join the scientists and engineers working to make life on the moon a reality.

On the 50th anniversary of the Apollo 8 mission, astronauts and engineers tell the inside story of the first mission to circumnavigate the moon.

On the 50th anniversary of the Apollo 8 mission, astronauts and engineers tell the inside story of the first mission to circumnavigate the moon.

An up-close look at faraway worlds. (Part 1 of 5)

An up-close look at faraway worlds. (Part 1 of 5)

(Part 2 of 5)

(Part 3 of 5)

(Part 2 of 5)

(Part 3 of 5)

NASA's Cassini explores Saturn for 13 years, looping through its icy rings and flying by its moons. The probe captures stunning ring-moon interactions, but when it finds the ingredients for life on the moon Enceladus, a bittersweet decision is made. (Part 3 of 5)

An up-close look at faraway worlds. (Part 1 of 5)

(Part 2 of 5)

An up-close look at faraway worlds. (Part 1 of 5)

(Part 2 of 5)

(Part 3 of 5)

(Part 3 of 5)

NASA's Cassini explores Saturn for 13 years, looping through its icy rings and flying by its moons. The probe captures stunning ring-moon interactions, but when it finds the ingredients for life on the moon Enceladus, a bittersweet decision is made. (Part 3 of 5)

NASA's Cassini explores Saturn for 13 years, looping through its icy rings and flying by its moons. The probe captures stunning ring-moon interactions, but when it finds the ingredients for life on the moon Enceladus, a bittersweet decision is made. (Part 3 of 5)

In the far reaches of the solar system, Uranus and Neptune dazzle with unexpected rings, supersonic winds and dozens of moons. And NASA's New Horizons gets a stunning up-close view of Pluto before venturing deep into the Kuiper Belt. (Part 4 of 5)

Join the mission as the New Horizons spacecraft attempts to fly by NASA's most distant target yet. Since it explored Pluto in 2015, New Horizons is zooming toward Ultima Thule, an object four billion miles from Earth.

In the far reaches of the solar system, Uranus and Neptune dazzle with unexpected rings, supersonic winds and dozens of moons. And NASA's New Horizons gets a stunning up-close view of Pluto before venturing deep into the Kuiper Belt. (Part 4 of 5)

Join the mission as the New Horizons spacecraft attempts to fly by NASA's most distant target yet. Since it explored Pluto in 2015, New Horizons is zooming toward Ultima Thule, an object four billion miles from Earth.

On the 50th anniversary of the Apollo 8 mission, astronauts and engineers tell the inside story of the first mission to circumnavigate the moon.

An up-close look at faraway worlds. (Part 1 of 5)

(Part 2 of 5)

An up-close look at faraway worlds. (Part 1 of 5)

(Part 2 of 5)

(Part 3 of 5)

(Part 3 of 5)

NASA's Cassini explores Saturn for 13 years, looping through its icy rings and flying by its moons. The probe captures stunning ring-moon interactions, but when it finds the ingredients for life on the moon Enceladus, a bittersweet decision is made. (Part 3 of 5)

NASA's Cassini explores Saturn for 13 years, looping through its icy rings and flying by its moons. The probe captures stunning ring-moon interactions, but when it finds the ingredients for life on the moon Enceladus, a bittersweet decision is made. (Part 3 of 5)

In the far reaches of the solar system, Uranus and Neptune dazzle with unexpected rings, supersonic winds and dozens of moons. And NASA's New Horizons gets a stunning up-close view of Pluto before venturing deep into the Kuiper Belt. (Part 4 of 5)

Join the mission as the New Horizons spacecraft attempts to fly by NASA's most distant target yet. Since it explored Pluto in 2015, New Horizons is zooming toward Ultima Thule, an object four billion miles from Earth.