“The early life and professional career of American astronaut John Glenn. Several of the people who knew him “back when” in New Concord, Ohio take up a certain amount of time reminiscing on Glenn’s boyhood and then segues into the astronaut’s preparations for his space flight — three orbits around the earth, and then home again. Included are interior shots aboard the Friendship Seven space capsule, and Glenn’s comments as he works inside the capsule during this mission.”
“As it orbits Sol, (469219) 2016 HO3 appears to circle around Earth as well. The object is beyond the Hill sphere of Earth, meaning that the Sun exerts a stronger pull on it than Earth does. Although it is too distant to be considered a true natural satellite of Earth, it is the best and most stable example to date of a near-Earth companion, or quasi-satellite.
“Since 2016 HO3 loops around our planet, but never ventures very far away as we both go around the sun, we refer to it as a quasi-satellite of Earth,” said Paul Chodas, manager of NASA’s Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California.
“One other asteroid — 2003 YN107 — followed a similar orbital pattern for a while over 10 years ago, but it has since departed our vicinity. This new asteroid is much more locked onto us. Our calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth’s companion for centuries to come.”
In its yearly trek around the sun, asteroid 2016 HO3 spends about half of the time closer to the sun than Earth is (that is, the asteroid is inside the Earth’s orbit) and passes ahead of our planet, and about half of the time farther away (crosses outside Earth’s orbit), causing it to fall behind. Its orbit is also tilted a little, causing it to bob up and then down once each year through Earth’s orbital plane. In effect, this small asteroid is caught in a game of leap frog with Earth that will last for hundreds of years.
The asteroid’s orbit also undergoes a slow, back-and-forth twist over multiple decades. “The asteroid’s loops around Earth drift a little ahead or behind from year to year, but when they drift too far forward or backward, Earth’s gravity is just strong enough to reverse the drift and hold onto the asteroid so that it never wanders farther away than about 100 times the distance of the moon,” said Chodas. “The same effect also prevents the asteroid from approaching much closer than about 38 times the distance of the moon. In effect, this small asteroid is caught in a little dance with Earth.”
Asteroid 2016 HO3 was first spotted on April 27, 2016, by the Pan-STARRS 1 asteroid survey telescope on HaleakalÄ, Hawaii, operated by the University of Hawaii’s Institute for Astronomy and funded by NASA’s Planetary Defense Coordination Office. The size of this object has not yet been firmly established, but it is likely about 40–100 m (130–330 ft).”
“Launched ten years ago, on Oct. 25, 2006, the twin spacecraft of NASA’s STEREO mission – short for Solar and Terrestrial Relations Observatory – have given us unprecedented views of the sun, including the first-ever simultaneous view of the entire star at once. This kind of comprehensive data is key to understanding how the sun erupts with things like coronal mass ejections and energetic particles, as well as how those events move through space, sometimes impacting Earth and other worlds. Ten years ago, the twin STEREO spacecraft joined a fleet of NASA spacecraft monitoring the sun and its influence on Earth and space – and they provided a new and unique perspective.
The two STEREO observatories, called STEREO-A and STEREO-B – for Ahead and Behind, respectively – were sent out from Earth in opposite directions. Using gravitational assists from both the moon and Earth, the STEREO spacecraft were accelerated to Earth-escape velocities. STEREO-A was inserted into an orbit slightly smaller, and therefore faster, than Earth’s. For STEREO-B, the reverse happened: It was nudged into an orbit slightly larger than Earth’s so that it traveled around the sun more slowly, falling increasingly behind the Earth. As the spacecraft slowly fanned out away from the centerline between Earth and the sun – where every other sun-watching spacecraft is located – they revealed more and more new information about our closest star.”
Video credit: NASA’s Goddard Space Flight Center/Genna Duberstein/Scott Wiessinger
“On Sept. 8, NASA launched the Origins Spectral Interpretation Resource Identification Security – Regolith Explorer, or OSIRIS-REx mission from Cape Canaveral Air Force Station in Florida. OSIRIS-REx is the first U.S. mission to sample an asteroid. The spacecraft is scheduled to arrive at near-Earth asteroid Bennu in 2018, survey the asteroid’s surface, retrieve at least 60 grams (2.1 ounces) of surface material, and return the sample to Earth in 2023 for study. Analysis of the sample will reveal the earliest stages of the solar system’s evolution and the history of Bennu over the past 4.5 billion years.”
“On Sept. 6, after bidding farewell to the crew remaining aboard the International Space Station, Expedition 48 Commander Jeff Williams of NASA and Soyuz Commander Alexey Ovchinin and Flight Engineer Oleg Skripochka of Roscosmos undocked from the orbital outpost to begin their return trip to Earth. They spent 172 days aboard the ISS, conducting research and operational work in support of the station.”
“The SpaceX CRS-9 Dragon cargo craft departed the International Space Station Aug. 26 after five weeks at the complex. Dragon delivered critical science experiments and the first International Docking Adapter to which U.S. commercial spacecraft will link up to in the future. Using the Canadarm2 robotic arm, Expedition 48 Commander Jeff Williams and Flight Engineer Kate Rubins released the Dragon and monitored the resupply spacecraft as it backed away to a safe distance from the station for its deorbit engine firing that would enable the ship to enter the Earth’s atmosphere for a parachute-assisted splashdown in the Pacific Ocean west of Baja California. Dragon returned about one and a half tons of science experiments and other cargo that will be collected once it reaches port in Long Beach, California. Dragon launched July 18 atop a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station in Florida and arrived at the station July 20.”
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