“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
“After saying farewell to the crew staying on the International Space Station and climbing into their Soyuz spacecraft on October 29, Expedition 49 Commander Anatoly Ivanishin of Roscosmos and Flight Engineers Kate Rubins of NASA and Takuya Onishi of the Japan Aerospace Exploration Agency, undocked from the orbital outpost, to begin their return trip to Earth. Ivanishin, Rubins and Onishi spent 115 days in space and 113 days aboard the orbital laboratory.”
“Loaded with more than 2.5 tons of supplies and science experiments, Orbital ATK’s Cygnus cargo craft arrived at the International Space Station Oct. 23 following its launch on a refurbished Antares rocket from the Wallops Flight Facility, Virginia Oct. 17. Expedition 49 crewmembers Takuya Onishi of the Japan Aerospace Exploration Agency and Kate Rubins of NASA captured Cygnus using the station’s Canadian-built robotic arm. Ground controllers then maneuvered Cygnus to the Earth-facing port of the Unity module where it was installed and bolted into place for a month-long stay.”
“The most recent series of payloads berthed with the International Space Station (ISS) Sunday morning onboard the Orbital ATK Cygnus capsule. Many of the investigations launched from Wallops Island, VA onboard the Antares rocket are sponsored by the ISS U.S. National Laboratory. The Center for the Advancement of Science in Space (CASIS) is tasked by NASA with managing and promoting research onboard the ISS National Laboratory for the benefit of Earth. Below provides a summary of the ISS National Laboratory-sponsored payloads delivered today:
CONTROLLED DYNAMICS LOCKER FOR MICROGRAVITY EXPERIMENTS ON ISS
Controlled Dynamics
Principal Investigator: Dr. Scott Green
Dr. Green and his team have developed a hardware platform that will provide research payloads with a “controlled dynamic acceleration environmentâ€â€”in other words, a technology that will dampen fluctuations/disturbances in the microgravity environment that occur onboard moving spacecraft. This technology promises to attract a new class of research experiments and private funding aimed at exploiting this controlled acceleration environment in microgravity, which has the potential to improve space experiments in crystallization; fluid physics; cell, tissue, and plant culturing; and other studies that require precise control of motion. This investigation stems from a CASIS grant supporting enabling technology development onboard the ISS National Lab.
NANORACKS BLACK BOX
NanoRacks, LLC
Principal Investigator: Mary Murphy
NanoRacks Black Box is a key part of NanoRacks’ next-generation ISS platforms. This new hardware is specially designed to provide near-launch payload turnover of autonomous payloads while providing advanced science capabilities for customers, including the use of robotics, new automated MixStix, and NanoLab-style research. OA-5 provides the first technology demonstration mission to test the NanoRacks Black Box platform, NanoRacks’ own payload hardware, and customer technology demonstration experiments. Technology demonstration payloads onboard OA-5 include multiple education-focused experiments, one of which features a partnership between Valley Christian High School in California and Microsoft, in which students will leverage the Microsoft Windows 10 IoT (internet of things) platform to run experiments on a cell phone motor to test the behaviors of different metals and materials in microgravity environments with status and magnetic forces.
NANORACKS EXTERNAL DEPLOYER
NanoRacks, LLC
Principal Investigators: Conor Brown and Henry Martin
NanoRacks provides opportunities for CubeSat deployment from Cygnus after the vehicle departs from the ISS. The NanoRacks deployer is installed on the exterior of the Cygnus service module, and after completion of its primary ISS resupply mission, Cygnus is intended to move into a higher orbit, and then deploy small satellites. Four satellites are part of the OA-5 mission intended to launch from Cygnus in partnership with the space-based data company, Spire. Spire’s solutions offer organizations near-real-time insights into weather and climate, shipping and supply chain, and maritime domain awareness. Ships carry 90% of global trade over the oceans, but the ships and those that rely on them are open to risks caused by delays, piracy, poor data for search and rescue operations, and incomplete data sets. The ship tracking payload reduces those risks by relaying critical metadata about oceangoing vessels to a network of ground stations. The weather observation payload gathers incredibly accurate temperature, pressure, and humidity data by recording and processing signals from GPS satellites as they “bend” through the Earth’s atmosphere. The data is fed into weather models, where it provides large improvements to short- and medium-term forecasts. This mission will incrementally increase Spire’s satellite constellation, providing additional coverage from a mid-inclination orbit.
SOLIDIFICATION USING A BAFFLE IN SEALED AMPOULES (SUBSA) FURNACE
NASA Marshall Space Flight Center
Material melt-growth experiments have been difficult to run in the space environment because there is just enough residual micro-acceleration (g-jitter) to produce natural convection that interferes with the structure and purity of the material. This convection is responsible for the lack of reliable and reproducible solidification data and, thus, for gaps in solidification theory. The Solidification Using a Baffle in Sealed Ampoules (SUBSA) experiment tested an automatically moving baffle (driven by melt expansion during freezing) that was designed to reduce thermal convection inside an ampoule to determine whether the baffle significantly reduces convection. Ground studies showed that the baffle reduces the movement of the material during its liquid phase, making the process easier to analyze and allowing more homogenous crystals to form. The key goal of SUBSA was to clarify the origin of the melt convection in space and to reduce the magnitude to the point that it does not interfere with the transport phenomena. This mission will provide updates to the hardware onboard the ISS to include modifications to the furnace and inserts to ensure future investigations run nominally.”
“Hurricane Nicole is currently a strong tropical cyclone moving away from the British Overseas Territory of Bermuda. It is the first major hurricane to directly impact or make landfall on the island since Hurricane Fabian in 2003. The fourteenth named storm, sixth hurricane and third major hurricane of the active 2016 Atlantic hurricane season, Nicole formed in the central Atlantic on October 4. The small, slow-moving storm defied forecasts by steadily organizing in spite of strong wind shear, and it rapidly intensified to a Category 2 hurricane on October 7. The wind shear finally took its toll by October 8, reducing Nicole to a weak tropical storm, but more favorable conditions allowed the cyclone to reintensify into a hurricane a couple days later. The storm’s approach to Bermuda forced schools, businesses, and government offices to close, while flight, bus, and ferry services were interrupted. On October 13, the eye of Category 3 Hurricane Nicole passed over Bermuda, producing damaging winds.”
“Rosetta was a space probe built by the European Space Agency launched on 2 March 2004. Along with Philae, its lander module, Rosetta performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft flew by Mars and the asteroids 21 Lutetia and 2867 Å teins.
On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvres to be captured in its orbit. On 12 November, the lander module performed the first successful landing on a comet, though its battery power ran out two days later. Communications with Philae were briefly restored in June and July 2015, but due to diminishing solar power, Rosetta’s communications module with the lander was turned off on 27 July 2016. On 30 September 2016, the Rosetta spacecraft ended its mission by landing on the comet in its Ma’at region.
The probe is named after the Rosetta Stone, a stele of Egyptian origin featuring a decree in three scripts. The lander is named after the Philae obelisk, which bears a bilingual Greek and Egyptian hieroglyphic inscription. A comparison of its hieroglyphs with those on the Rosetta Stone catalysed the deciphering of the Egyptian writing system. Similarly, it is hoped that these spacecraft will result in better understanding of comets and the early Solar System. In a more direct analogy to its namesake, the Rosetta spacecraft also carries a micro-etched nickel alloy Rosetta disc donated by the Long Now Foundation inscribed with 13,000 pages of text in 1,200 languages.”
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