The New Horizons spacecraft attempts to fly by Ultima Thule, an object four billion miles from Earth.

The New Horizons spacecraft attempts to fly by Ultima Thule, an object four billion miles from Earth.

Physicists capture light from across the universe in a bid to prove quantum entanglement.

Physicists capture light from across the universe in a bid to prove quantum entanglement.

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours and months after the impact.

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours and months after the impact.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours and months after the impact.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Take a risky dive into an underwater cave in Mexico to discover the 13,000-year-old skeleton of a prehistoric teenager. Follow forensic clues that reveal intimate details of her life and death, and how her people first ventured into North America.

Take a risky dive into an underwater cave in Mexico to discover the 13,000-year-old skeleton of a prehistoric teenager. Follow forensic clues that reveal intimate details of her life and death, and how her people first ventured into North America.

How did the ancient Egyptians build the pyramids of Giza with only copper hand tools and none of today's construction and surveying equipment? Who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? Here is the latest evidence from the groundbreaking research of archaeologists Mark Lehner and Zahi Hawass as well as French archaeologist Pierre Tallet, whose team found the world's oldest writing on papyrus.

How did the ancient Egyptians build the pyramids of Giza with only copper hand tools and none of today's construction and surveying equipment? Who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? Here is the latest evidence from the groundbreaking research of archaeologists Mark Lehner and Zahi Hawass as well as French archaeologist Pierre Tallet, whose team found the world's oldest writing on papyrus.

We may be witnessing the dawn of a bold new era of human activity in space -- for science and exploration, but also for profit. An explosion of private companies are developing new technologies and lowering costs to bring space closer than ever. And at the same time, NASA is returning to manned spaceflight with gusto -- once again building a rocket to take us far beyond Earth -- a rocket more powerful even than the storied Saturn V.

We may be witnessing the dawn of a bold new era of human activity in space -- for science and exploration, but also for profit. An explosion of private companies are developing new technologies and lowering costs to bring space closer than ever. And at the same time, NASA is returning to manned spaceflight with gusto -- once again building a rocket to take us far beyond Earth -- a rocket more powerful even than the storied Saturn V.

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours and months after the impact.

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours and months after the impact.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Join scientists and residents on a breathtaking journey to investigate the Kilauea volcano's recent spike in activity, including the deadly April 2017 eruption. Along the way, some of Hawaii's biggest secrets are revealed.

Take a risky dive into an underwater cave in Mexico to discover the 13,000-year-old skeleton of a prehistoric teenager. Follow forensic clues that reveal intimate details of her life and death, and how her people first ventured into North America.

Take a risky dive into an underwater cave in Mexico to discover the 13,000-year-old skeleton of a prehistoric teenager. Follow forensic clues that reveal intimate details of her life and death, and how her people first ventured into North America.

How did the ancient Egyptians build the pyramids of Giza with only copper hand tools and none of today's construction and surveying equipment? Who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? Here is the latest evidence from the groundbreaking research of archaeologists Mark Lehner and Zahi Hawass as well as French archaeologist Pierre Tallet, whose team found the world's oldest writing on papyrus.

How did the ancient Egyptians build the pyramids of Giza with only copper hand tools and none of today's construction and surveying equipment? Who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? Here is the latest evidence from the groundbreaking research of archaeologists Mark Lehner and Zahi Hawass as well as French archaeologist Pierre Tallet, whose team found the world's oldest writing on papyrus.

How did the ancient Egyptians build the pyramids of Giza with only copper hand tools and none of today's construction and surveying equipment? Who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? Here is the latest evidence from the groundbreaking research of archaeologists Mark Lehner and Zahi Hawass as well as French archaeologist Pierre Tallet, whose team found the world's oldest writing on papyrus.

We may be witnessing the dawn of a bold new era of human activity in space -- for science and exploration, but also for profit. An explosion of private companies are developing new technologies and lowering costs to bring space closer than ever. And at the same time, NASA is returning to manned spaceflight with gusto -- once again building a rocket to take us far beyond Earth -- a rocket more powerful even than the storied Saturn V.