November 1902
Robert Scott, Edward Wilson and Ernest Shackleton make the first attempt to reach the South Pole. They covered over 700 miles and reached a latitude of 82 degrees south before being forced to turn back.

April 1908
Great Britain's Ernest Shackleton, Frank Wild, Eric Marshall and Jameson Adams begin their attempt to reach the South Pole. Only 112 miles from the Pole, in poor health and near starvation, they are forced to cut short their quest.

January 1909
Edgeworth David, Douglas Mawson and Alistar McKay reach the South Magnetic Pole.

April 1909
Robert Peary, having started his dash to the North Pole a month earlier, reaches his destination on April 6th. 

December 1911
Norwegian  Roald Amundsen, along with four others, arrives at the South Pole.

January 1912
Englishmen Robert Scott, Edward Wilson, Henry Bowers, Edgar Evans and Lawrence Oates reach the South Pole. Scott's log of the event reads, "Great God! This is an awful place and terrible enough for us to have laboured to it without the reward of priority." 

March 1912
Scott, Wilson, and Bowers die on their return journey. They were only 11 miles from the next depot spot where provisions were awaiting them.

October 1915
Determined "to start a last great journey" Ernest Shackleton attempts to cross Antarctica. Shackleton never reaches the continent, however. His ship, "The Endurance, " is stuck in a Weddell Sea ice pack for 281 days before finally being crushed. Shackleton and crew were able to escape the doomed vessel and take refuge on Elephant Island.

April 1916
Ernest Shackleton and crew head out from Elephant Island in a makeshift open sea craft. Following a voyage of 16 days they arrived at South Georgia, also in Antarctica. Determined to reach a whaling station at Stromness, Shackleton and crew set across the frozen island on foot. Although his expedition failed in its stated objective, Shackleton considered the trek a success. "The comradeship and resource of the members...was worthy of the highest traditions of Polar service," he later declared.

May 1926
Americans Richard E. Byrd and Floyd Bennett are the first to fly over the North Pole. The veracity of their feat will later be called into question and will be the subject of controversial debate for years to come. 

December 1928
Australia's Sir George Hubert Wilkins is the first man to fly over Antarctica.

November 1929
Operating out of his base, Little America, on the Bay of Whales, Richard E. Byrd, along with three others, completes a 1600-mile flight over the South Pole.

August 1934
Naturalist and explorer William Beebe and engineer Otis Barton set out to plunge deeper into the ocean than anyone had ever gone. Through the use of a bathysphere, Beebe and Barton descended to a record-setting depth of 3,028 feet off the coast of Bermuda. The record stands for fifteen years before Barton himself breaks it. 

April 1947
Norwegian scientist and explorer, Thor Heyerdahl, sets out to cross the Pacific Ocean in boat made of balsa logs, bamboo, and hemp to "support a theory that the South Sea islands were peopled from Peru." His vessel, the "Kon-Tiki", carried a crew of six from Peru and arrived in Tahiti 108 days later. 

May 1953
New Zealander Edmund Hillary, along with Nepalese guide Tenzing Norgay, completes the first successful ascent of Mount Everest. 

August 1958
The U.S. nuclear-powered submarine the "Nautilus", commandeered by William R. Anderson, becomes the first ship to cross beneath the entire length of the North Pole.

April 1961
Soviet Yuri A. Gagarin, traveling aboard the "Vostok 1", becomes the first human in space. Gagarin spends one hour and forty-eight minutes on his orbital flight.

May 1961
Alan B. Shepard, riding the "Mercury-Redstone 3", is the first American astronaut in space. His flight lasts 15 minutes.

February 1962
John Glenn a Marine Corps pilot, becomes the first American to orbit the earth. Glenn's mode of transportation is the Mercury capsule, "Friendship 7".

February 1963
The longest non-stop flight ever completed over the South Pole is made by a U.S. plane. A distance of 3,600 miles is covered in ten hours. The flight path went from McMurdo Station, past the geographical South Pole to Shackleton Mountains, and continued southeast to the "Area of Inaccessibility" before returning to the McMurdo Station. 

June 1963
Valentina V. Tereshkova of the Soviet Union is the first woman in space. Tereshkova enters space aboard the "Vostok 6".

March 1965
While flying aboard the "Voskhod 2" with cosmonaut Pavel I. Belyayev, fellow Soviet Aleksei A. Leonov becomes the first man to embark on a "space walk." The event lasts approximately ten minutes.

June 1965
Spending approximately 20 minutes outside of his "Gemini 4" spacecraft, Edward White becomes the first American astronaut to walk in space.

December 1968
The "Apollo 8", carrying U.S. astronauts Frank Borman, James Lovell, and William A. Anders, becomes the first manned space vessel to orbit the moon. 

July 1969
U.S. astronauts Neil Armstrong and Edwin "Buzz" Aldrin, part of the "Apollo 11" crew, along with astronaut Michael Collins, successfully execute the first manned lunar landing. While Collins stayed in the spacecraft , Armstrong and Aldrin walked upon the surface of the moon. Armstrong, the first man to walk on the moon described it this way: "The surface is fine and powdery. It adheres in fine layers, like powdered charcoal, to the soles and sides of my boots. I only go in a fraction of an inch, maybe an eighth of an inch, but I can see the footprints of my boots and the treads in the fine, sandy particles."

July 1975
The United States and the Soviet Union team up to launch the first international manned space mission. The mission goes under the name of the Apollo-Soyuz Test Project. 

August 1975
The U.S. launches "Viking I", a space probe bound for Mars. "Viking I" landed on Mars in July, 1976 and remained there for over six years. The unmanned probe transmitted pictures of the planet's surface and conducted research. 

August 1977
The Soviet nuclear-powered icebreaker "Arktika" reaches the North Pole and becomes the first surface ship to break through the Arctic ice pack to the top of the world. 

April 1978
Fending off attacks by polar bears, Japanese explorer Naomi Uemura becomes the first man to reach the North Pole alone by way of dog sled. Uemura traveled 600 miles over a period of 54 days.

April 1981
The United States launches the space shuttle "Columbia", the first re-usable manned spacecraft.

April 1982
British explorers Sir Ranulph Fiennes and Charles Burton reach the North Pole and establish themselves as the first party to circle the earth from pole to pole. The two had reached the South Pole 16 months earlier. The entire expedition took three years and cost an estimated $18 million.

June 1983
Sally Ride, one of the crew of the space shuttle "Challenger", becomes the first U.S. woman in space.

January 1986
The space shuttle "Challenger" explodes soon after lift off, killing all seven crew members aboard. Among the crew was a civilian, Christa McAuliffe, a school teacher from New Hampshire.

May 1986
Assisted only by sled dogs, a team of American and Canadian explorer -- Will Steger, Paul Schurke, Anne Bancroft, Geoff Carroll, Brent Boddy, and Richard Weber -- reach the North Pole without the benefit of mechanical assistance. The team traveled a distance of 500 miles over 56 days. 

January 1989
Traveling with a team of nine others, Shirley Metz and Victoria Murden become the first women and the first Americans to reach the South Pole over land. Along with the other members of their team, the two traversed 740 miles on skis over a period of 51 days.

September 1992
U.S. astronaut Mae Carol Jemison becomes the first African-American woman to travel in space. Jemison was part of the crew of the space shuttle "Endeavour".

April 1993
Ellen Ochoa, one of the crew of the U.S. space shuttle "Discovery", becomes the first Hispanic woman in space. 

July 1997
NASA's Mars Pathfinder mission, three years in the making, places a science payload on the surface of the Red Planet and demonstrates the mobility and usefulness of a micro-rover on Mar's surface. Live pictures are beamed back to earth and broadcast over international television.

October 1998
Thirty-six years after being the first American to orbit the earth, 77-year-old John Glenn acts as payload specialist onboard the space shuttle "Discovery". Glenn volunteered for the mission in order to take part in a series of experiments related to age and space travel. Glenn is the oldest person to travel in space.