Stories tagged orbit
Was it way too hot for you to get out yesterday for the holiday? Then take this cool spin around our planet with this time-lapse video composed of images from NASA's Image Science & Analysis Laboratory, NASA Johnson Space Center.
Tags : Time-lapse taken by astronaut Don Pettit from the airlock of the Russian segment aboard the ISS. Here's a related article on the Smithsonian's Air & Space magazine website. That's amoré!
Neptune Anniversary ImagesCourtesy NASA, ESA, and the Hubble Heritage Team (STScI/AURA)Neptune arrived today at the same location in space where it was discovered nearly 165 years ago. To commemorate the event, NASA's Hubble Space Telescope took these "anniversary pictures" of the blue-green giant planet.
Neptune is the most distant major planet in our solar system (alas, poor Pluto). German astronomer Johann Galle discovered the planet on September 23, 1846. The planet is 2.8 billion miles (4.5 billion kilometers) from the Sun. Under the Sun's weak pull at that distance, Neptune plods along in its huge orbit, slowly completing one revolution approximately every 165 years. Due to this slow orbit, each of Neptune's "seasons" lasts for about 40 years.
The four Hubble images of Neptune were taken with the Wide Field Camera 3 on June 25-26, during the planet's 16-hour rotation. The snapshots were taken at roughly four-hour intervals, offering a full view of the planet. The images reveal high-altitude clouds in the northern and southern hemispheres. The clouds are composed of methane ice crystals.
Each week, CNN posts a collection of space images. This week, you can see the green comet Lulin, thousands of satellites orbiting Earth, and some photos from the Hubble Space Telescope.
Sputnik 1 starts space race 50 years ago
Sputnik 1: Oct. 4, 1957The "Sputnik crisis" was a turning point of the Cold War that began on October 4, 1957 when the Soviet Union launched the Sputnik 1 satellite. With its intercontinental ballistic missile, the R-7 Semyorka, Russia was first out of the starting blocks in the space race.
The "simplest satellite"
Called PS-1, for "Prosteishiy Sputnik" — the Simplest Satellite, Sputnik 1 weighing just 184 pounds, was built in less than three months. Soviet designers built a pressurized sphere of polished aluminum alloy with two radio transmitters and four antennas.
Sergey Korolyov
Sergey Korolyov, both visionary scientist and iron-willed manager, pressed the Kremlin to let him launch a satellite. The reaction of the world so impressed Khrushchev that he pressed Korolyov to do it again. Working round-the-clock, Korolyov and his team built another spacecraft in less than a month. On Nov. 3, they launched Sputnik 2, which weighed 1,118 pounds. It carried the world's first living payload, a mongrel dog named Laika, in its tiny pressurized cabin.
Sputnik creates initiatives in science and math
The Sputnik crisis spurred a whole chain of U.S. initiatives, including NASA, NSF, DARPA, and even the "New Math".
The finish line - stepping on the Moon
Russia continued its lead in the space race with a moon probe, a photo of the far side of the Moon, a human in orbit, a woman in orbit, extra-vehicular activity, landing a probe on another planet (Venus), and the first space station. The United States captured the biggest prize, though, putting a human on the Moon (July 20, 1969).
Wobbly planet Earth: Photo courtesy NASA.
The extinction of rodents and other mammals have been linked to variations in the Earth’s tilt and orbit, according to new research published in the journal Nature.
Dutch scientists studying 22 million year old rodent fossils in central Spain found that the rise and fall of the mammal species correlated with cooling periods due to changes in the Earth’s behavior. Rodents offer one of the best fossil mammal records and are excellent indicators of seasonal changes because of their short life spans.
"Extinctions in rodent species occur in pulses which are spaced by intervals controlled by astronomical variations and their effects on climate change," Dr Jan van Dam, of the Utrecht University in the Netherlands, said.
The researchers discovered two cycles associated with changes in climate, habitat and food availability are linked to the disappearance of rodent species. One cycle, which lasts 2.4 million years, is linked to variations in the Earth’s orbit. The other 1.2 million year cycle is related to changes in the tilt of the Earth’s axis. Both cycles would cool the Earth, allowing the expansion of ice sheets and causing species to adapt or die out.
Right now Earth is in a relatively circular orbit and about 700,000 years away from the next period of axis stability.
"The environment is responsible to what happens to species," said Van Dam. "Biological factors are secondary, according to our results."
However, Larry Ciupik, an astronomer at Chicago’s Adler Planetarium says volcanic activities, plate tectonics and the amount of carbon dioxide in the atmosphere also contribute to species turnover.
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