On April 10, 1815, Mount Tambora sent so much crud into the atmosphere that it blocked the sun. What became known as the Year Without a Summer came a year later, in 1816.
Posts by Elizabeth Howell
William Herschel noticed while surveying stars that one object moved apart from the star background. It was the first planet discovered since ancient times.
On February 20, 1962, John Glenn became the first American to orbit the Earth. He made three turns around the planet before returning safely.
Today is the 101st anniversary of the Great Meteor Procession, in which bright meteors were seen to cross the sky on stately, nearly identical paths.
On January, 23, 1960, the bathyscaphe Trieste made a record-setting dive to the deepest known part of the ocean.
Isaac Newton was born on December 25, 1642. His work laid much of the foundation for our modern understanding of the physical universe.
Mass and energy are interchangeable.
Pioneer 11 was the first spacecraft ever to encounter Saturn. It paved the way for the even-more-sophisticated Voyager spacecraft.
When the NASA spacecraft Voyager 2 skimmed by Neptune, it acquired images of a faint, continuous ring system encircling the planet.
Voyager 2 realized the vision of what was originally called a Grand Tour of the outer solar system. It remains the only craft to have visited all four outer planets.