OrbitalHub

Wikipedia dixit:

“Earth Observing-1 (EO-1) is a NASA Earth observation satellite created to develop and validate a number of instrument and spacecraft bus breakthrough technologies. These will enable the development of future Earth imaging observatories that will have a significant increase in performance while also having reduced cost and mass. The spacecraft is part of the New Millennium Program.

Its Advanced Land Imager (ALI) measures nine different wavelengths simultaneously, instead of the seven measured by the imager in Landsat 7. This permits a greater flexibility in false-color imagery. Another improvement is that instead of having an imaging spectrometer that sweeps from side to side, the ALI has a linear array of spectrometers that each scan a strip of ground parallel to that of adjacent spectrometers. In order to compare the two imagers, EO-1 follows Landsat 7 in its orbit by exactly one minute. Other new technologies include: Hyperion imaging spectrometer recording more than 200 wavelengths; phased array communications antenna; optical fiber cables connect the data logger with the two IBM RAD6000s; teflon-fueled pulsed plasma thruster; lightweight, flexible solar panel; carbon-coated radiators for thermal control; Linear Etalon Imaging Spectrometer Array equipped with a new atmospheric correction device.

EO-1 has also been used to test new software, like the Autonomous Sciencecraft Experiment. This allows the spacecraft to decide for itself how best to create a desired image. It is only limited by a priority list of different types of images, and by forecasts of cloud cover provided by the NOAA.

It was expected to function for twelve months and was designed to function for eighteen months. Those expectations were greatly exceeded however the hydrazine fuel was mostly depleted in February 2011. Small maneuvers have been successful for debris avoidance but long duration burns for orbit maintenance are not being performed due to insufficient fuel. EO-1 was deactivated on 30 March 2017. At its current altitude, it is estimated that the satellite will remain in orbit until the 2050s, when it will burn up in Earth’s atmosphere.”

Video credit: NASA Goddard

NASA dixit:

“The SpaceX/Dragon cargo ship arrived at the International Space Station after a two-day journey to deliver about 7,600 pounds of supplies and science experiments to the Expedition 52 crew. Following its launch atop the SpaceX Falcon 9 rocket June 3 from the Kennedy Space Center, Florida, Dragon was captured by Expedition 52 Flight Engineer Jack Fischer of NASA using the station’s Canadian-built robotic arm. Ground controllers then took control of the robotic arm, maneuvering Dragon to the Earth-facing port of the Harmony module, where it was installed and bolted into place. Dragon is scheduled to remain at the station for a month before it is unberthed and deorbited for a parachute-assisted splashdown in the Pacific Ocean.”

Video credit: NASA

NASA dixit:

“Expedition 51 Flight Engineer and Soyuz Commander Oleg Novitskiy of the Russian Federal Space Agency (Roscosmos) and Flight Engineer Thomas Pesquet of ESA (European Space Agency) landed safely near the town of Dzhezkazgan, Kazakhstan June 2 after bidding farewell to their colleagues on the International Space Station and undocking their Soyuz MS-03 spacecraft from the Rassvet Module on the Russian segment of the complex. The two crew members spent 196 days in space overall and 194 days on the station conducting research and operational work.”

Video credit: NASA / Roscosmos

NASA dixit:

“On Mars, wind rules. Wind has been shaping the Red Planet’s landscapes for billions of years and continues to do so today. Studies using both a NASA orbiter and a rover reveal its effects on scales grand to tiny on the strangely structured landscapes within Gale Crater.

NASA’s Curiosity Mars rover, on the lower slope of Mount Sharp — a layered mountain inside the crater — has begun a second campaign of investigating active sand dunes on the mountain’s northwestern flank. The rover also has been observing whirlwinds carrying dust and checking how far the wind moves grains of sand in a single day’s time.

Gale Crater observations by NASA’s Mars Reconnaissance Orbiter have confirmed long-term patterns and rates of wind erosion that help explain the oddity of having a layered mountain in the middle of an impact crater.

“The orbiter perspective gives us the bigger picture — on all sides of Mount Sharp and the regional context for Gale Crater. We combine that with the local detail and ground-truth we get from the rover,” said Mackenzie Day of the University of Texas, Austin, lead author of a research report in the journal Icarus about wind’s dominant role at Gale.

The combined observations show that wind patterns in the crater today differ from when winds from the north removed the material that once filled the space between Mount Sharp and the crater rim. Now, Mount Sharp itself has become a major factor in determining local wind directions. Wind shaped the mountain; now the mountain shapes the wind.

The Martian atmosphere is about a hundred times thinner than Earth’s, so winds on Mars exert much less force than winds on Earth. Time is the factor that makes Martian winds so dominant in shaping the landscape. Most forces that shape Earth’s landscapes — water that erodes and moves sediments, tectonic activity that builds mountains and recycles the planet’s crust, active volcanism — haven’t influenced Mars much for billions of years. Sand transported by wind, even if infrequent, can whittle away Martian landscapes over that much time.”

Video credit: NASA Jet Propulsion Laboratory

NASA Goddard dixit:

“From long, tapered jets to massive explosions of solar material and energy, eruptions on the sun come in many shapes and sizes. Since they erupt at such vastly different scales, jets and the massive clouds — called coronal mass ejections, or CMEs — were previously thought to be driven by different processes.

Scientists from Durham University in the United Kingdom and NASA now propose that a universal mechanism can explain the whole spectrum of solar eruptions. They used 3-D computer simulations to demonstrate that a variety of eruptions can theoretically be thought of as the same kind of event, only in different sizes and manifested in different ways.

The study was motivated by high-resolution observations of filaments from NASA’s Solar Dynamics Observatory, or SDO, and the joint Japan Aerospace Exploration Agency/NASA Hinode satellite. Filaments are dark, serpentine structures that are suspended above the sun’s surface and consist of dense, cold solar material. The onset of CME eruptions had long been known to be associated with filaments, but improved observations have recently shown that jets have similar filament-like structures before eruption too. So the scientists set out to see if they could get their computer simulations to link filaments to jet eruptions as well.

Solar scientists can use computer models like this to help round out their understanding of the observations they see through space telescopes. The models can be used to test different theories, essentially creating simulated experiments that cannot, of course, be performed on an actual star in real life.

The scientists call their proposed mechanism for how these filaments lead to eruptions the breakout model, for the way the stressed filament pushes relentlessly at — and ultimately breaks through — its magnetic restraints into space. They previously used this model to describe CMEs; in this study, the scientists adapted the model to smaller events and were able to reproduce jets in the computer simulations that match the SDO and Hinode observations. Such simulations provide additional confirmation to support the observations that first suggested coronal jets and CMEs are caused in the same way.”

Video credit: NASA’s Goddard Space Flight Center/Genna Duberstein

NASA dixit:

“NASA’s Fermi Gamma-ray Space Telescope has found a signal at the center of the neighboring Andromeda galaxy that could indicate the presence of the mysterious stuff known as dark matter. The gamma-ray signal is similar to one seen by Fermi at the center of our own Milky Way galaxy. Gamma rays are the highest-energy form of light, produced by the universe’s most energetic phenomena. They’re common in galaxies like the Milky Way because cosmic rays, particles moving near the speed of light, produce gamma rays when they interact with interstellar gas clouds and starlight. Surprisingly, the latest Fermi data shows the gamma rays in Andromeda, also known as M31, are confined to the galaxy’s center instead of spread throughout. To explain this unusual distribution, scientists are proposing that the emission may come from several undetermined sources. One of them could be dark matter, an unknown substance that makes up most of the universe.”

Video credit: NASA’s Goddard Space Flight Center/Scott Wiessinger