Recovery of the Test Orion Capsule in the Pacific Ocean
On Nov. 1, 2018, the USS John P. Murtha recovered the test version of the Orion capsule at sunset in the Pacific Ocean. The Underway Recovery Test-7 (URT-7) is one in a series of tests that the Exploration Ground Systems Recovery Team, along with the U.S. Navy, are conducting to validate procedures and hardware that will be used to recover the Orion spacecraft after it splashes down following deep space exploration missions. Orion will have the capability to sustain the crew during space travel, provide safe re-entry from deep space return velocities, and emergency abort.
Photo edited by NASA/Ron Beard, Photo credit: NASA/Tony Gray
The biggest obstacles a human would encounter living on the moon is cosmic radiation. Unlike the Earth, the moon has no atmosphere and no magnetic field. A person on its surface could receive over 400 times the maximum safe dosage of heavy ion radiation, enough to be fatal within ten hours, even in a spacesuit.
On the night of January 1, 1801, Giuseppe Piazzi, a priest in Palermo, Italy, was mapping the stars in the sky. Over three nights, he’d look at and draw the same set of stars, carefully measuring their relative positions.
That night, he measured the stars. The next night, he measured them again. To his surprise, one had moved. The third night, the peculiar star had moved again. This meant it couldn’t be a star at all.
It was something new, the first asteroid ever discovered, which Piazzi eventually named Ceres. Asteroids are bits of rock and metal that orbit the Sun. At over 900 kilometers across, Ceres is a very large asteroid. But through a telescope, like Piazzi’s, Ceres looked like a pinpoint of light similar to a star. In fact, the word asteroid means star-like. You can tell the difference between stars and asteroids by the way they move across the sky. Of course, Piazzi knew none of that at the time, just that he had discovered something new. To learn about Ceres, Piazzi needed to track its motion across the sky and then calculate its orbit around the Sun.
So each clear night, Piazzi trained his telescope to the heavens. Night after night, he made careful measurements, but from his observations he learned that Ceres was only visible in the sky during the day. It would take another year and a lot of astronomers to nail down Ceres’ path, but we haven’t lost track of it since.
Today, we can do something that Piazzi could only dream of: send spacecraft to study asteroids up close. One spacecraft called Dawn journeyed billions of kilometers over four years to the main asteroid belt. There, it visited Ceres and another asteroid, Vesta. Dawn’s stunning images transformed Piazzi’s dot of light into a spectacular landscape of craters, landslides, and mountains.
If you lived on the moon, you’d have to exercise for hours a day to maintain bone and muscle mass. That’s because the moon’s gravity is just one-sixth that of the Earth, and the everyday strain of working against gravity is part of what keeps our bodies healthy.
As of 1989, mankind had successfully sent craft to every known planet in the solar system except one—Pluto.
You may have heard that astronomers don’t consider Pluto or its brethren to be planets. However, most planetary scientists still do, which is why we’re using that terminology here. There’s a limited amount we can learn about Pluto from Earth because it’s so far from us.
Pluto, however, is a scientific goldmine. It’s located in a region called the Kuiper Belt, home to many small planets, hundreds of thousands of ancient icy objects, and trillions of comets. This mysterious region holds clues to the formation of our solar system, and it was long, tantalizingly beyond our reach.
Until New Horizons. Its objectives: explore Pluto, collect as much scientific data as possible, transmit it back to Earth, then explore farther out in the Kuiper Belt. To achieve this, the New Horizons team outfitted their craft with seven state-of-the-art scientific instruments.
To see how New Horizons got to Pluto in time, let’s jump to its launch. Its three rocket stages accelerated New Horizons to such great speeds that it crossed the 400,000 kilometers to the moon in just nine hours. About a year later, the craft reached Jupiter and got what’s called a gravity assist. That’s where it flies close enough to the gas giant to receive a gravitational slingshot effect. New Horizons was then flying at around 50,000 kilometers per hour, as it would for the next eight years to cross the remaining gulf to Pluto.
Going at such an astonishing speed meant that slowing down to get into orbit or land would’ve been impossible. That’s why New Horizons was on a flyby mission, where it would get just one chance to scream by Pluto and make its observations. The flyby would have to be fully automated, since at that distance, any signals to guide it from Earth would take 4.5 hours to reach it. So the team loaded the ship’s computer with a series of thousands of commands, called the core load, that would begin to execute when the craft was 6.5 days from Pluto. But when New Horizons was just ten days out, disaster almost struck. Ground control lost contact with the spacecraft. After two nerve-wracking hours, New Horizons came back online, but mission control discovered that its main computer had rebooted, losing the entire core load and other critical data. Without that, it would soon whizz by Pluto with virtually nothing to show for the mission. Alice Bowman, the mission’s Operations Manager, led a team for 72 sleepless hours to get the instructions loaded back into New Horizons in time. Without room for a single error, she and her team pulled it off, and New Horizons began taking and broadcasting breathtaking images. Those observations have revealed a delightfully varied world, with ground fogs, high altitude hazes, possible clouds, canyons, towering mountains, faults, craters, polar caps, glaciers, apparent dune fields, suspected ice volcanoes, evidence for past flowing liquids, and more.
The exploration of Pluto was a great success, but New Horizons isn’t done yet. On January 1, 2019, it’ll break its own record for furthest explored object when it visits a Kuiper Belt Object called 2014 MU69, which is orbiting the sun another billion kilometers farther away than Pluto. The world is holding its breath to see what it’ll find there.