“NASA GSFC solar scientist Holly Gilbert explains a computer model of the sun’s magnetic field.
Grasping what drives that magnetic system is crucial for understanding the nature of space throughout the solar system: The sun’s invisible magnetic field is responsible for everything from the solar explosions that cause space weather on Earth – such as auroras – to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel.
We can observe the shape of the magnetic fields above the sun’s surface because they guide the motion of that plasma – the loops and towers of material in the corona glow brightly in EUV images. Additionally, the footpoints on the sun’s surface, or photosphere, of these magnetic loops can be more precisely measured using an instrument called a magnetograph, which measures the strength and direction of magnetic fields.
Scientists also turn to models. They combine their observations – measurements of the magnetic field strength and direction on the solar surface – with an understanding of how solar material moves and magnetism to fill in the gaps. Simulations such as the Potential Field Source Surface, or PFSS, model – shown in the accompanying video – can help illustrate exactly how magnetic fields undulate around the sun. Models like PFSS can give us a good idea of what the solar magnetic field looks like in the sun’s corona and even on the sun’s far side.”
“Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. The US$720 million spacecraft was built by Lockheed Martin under the supervision of the Jet Propulsion Laboratory (JPL). The mission is managed by the California Institute of Technology, at the JPL, in La Cañada Flintridge, California, for the NASA Science Mission Directorate, Washington, D.C. It was launched August 12, 2005, and attained Martian orbit on March 10, 2006. In November 2006, after five months of aerobraking, it entered its final science orbit and began its primary science phase. As MRO entered orbit, it joined five other active spacecraft that were either in orbit or on the planet’s surface: Mars Global Surveyor, Mars Express, 2001 Mars Odyssey, and the two Mars Exploration Rovers (Spirit and Opportunity); at the time, this set a record for the most operational spacecraft in the immediate vicinity of Mars. Mars Global Surveyor and the Spirit rover have since ceased to function; the remainder remain operational as of March 2016.
MRO contains a host of scientific instruments such as cameras, spectrometers, and radar, which are used to analyze the landforms, stratigraphy, minerals, and ice of Mars. It paves the way for future spacecraft by monitoring Mars’ daily weather and surface conditions, studying potential landing sites, and hosting a new telecommunications system. MRO’s telecommunications system will transfer more data back to Earth than all previous interplanetary missions combined, and MRO will serve as a highly capable relay satellite for future missions.[…]
On September 29, 2006 (sol 402), MRO took its first high resolution image from its science orbit. This image is said to resolve items as small as 90 cm (3 feet) in diameter. On October 6, NASA released detailed pictures from the MRO of Victoria crater along with the Opportunity rover on the rim above it. In November, problems began to surface in the operation of two MRO spacecraft instruments. A stepping mechanism in the Mars Climate Sounder (MCS) skipped on multiple occasions resulting in a field of view that is slightly out of position. By December normal operations of the instrument was suspended, although a mitigation strategy allows the instrument to continue making most of its intended observations. Also, an increase in noise and resulting bad pixels has been observed in several CCDs of the High Resolution Imaging Science Experiment (HiRISE). Operation of this camera with a longer warm-up time has alleviated the issue. However, the cause is still unknown and may return.
HiRISE continues to return images that have enabled discoveries regarding the geology of Mars. Foremost among these is the announcement of banded terrain observations indicating the presence and action of liquid carbon dioxide (CO2) or water on the surface of Mars in its recent geological past. HiRISE was able to photograph the Phoenix lander during its parachuted descent to Vastitas Borealis on May 25, 2008 (sol 990).
The orbiter continued to experience recurring problems in 2009, including four spontaneous resets, culminating in a four-month shut-down of the spacecraft from August to December. While engineers have not determined the cause of the recurrent resets, they have created new software to help troubleshoot the problem should it recur.
On March 3, 2010, the Mars Reconnaissance Orbiter passed another significant milestone, having transmitted over 100 terabits of data back to Earth, which was more than all other interplanetary probes sent from Earth combined.
On August 6, 2012 (sol 2483), the orbiter passed over Gale crater, the landing site of the Mars Science Laboratory mission, during its EDL phase. It captured an image via the HiRISE camera of the Curiosity rover descending with its backshell and supersonic parachute.
NASA reported that the Mars Reconnaissance Orbiter, as well as the Mars Odyssey Orbiter and MAVEN orbiter had a chance to study the Comet Siding Spring flyby on October 19, 2014.
On July 29, 2015, the Mars Reconnaissance Orbiter was placed into a new orbit to provide communications support during the arrival of the InSight Mars lander mission on September 28, 2016. The maneuver’s engine burn lasted for 75 seconds.”
“The most powerful version of the Atlas V available launched […] from Space Launch Complex 41 at Cape Canaveral in Florida. The nearly 63 meter tall rocket with Russian powered RD 180 engine and five solid rocket motors boosted the Mobile User Objective System 5 (MUOS-5) satellite into orbit for the US Navy. MUOS provides vital communications and connectivity to armed forces around the globe. This was the fifth and final MUOS satellite to complete the first generation fleet.”
“The Mobile User Objective System (MUOS) is an Ultra High Frequency (UHF) (300 MHz to 3 GHz frequency range) SATCOM system, primarily serving the United States Department of Defense (DoD). International allies use is under consideration. The MUOS will replace the legacy UHF Follow-On (UFO) system before that system reaches its end of life to provide users with new capabilities and enhanced mobility, access, capacity, and quality of service. Intended primarily for mobile users (e.g. aerial and maritime platforms, ground vehicles, and dismounted soldiers), MUOS will extend users’ voice, data, and video communications beyond their lines-of-sight.
MUOS is an array of geosynchronous satellites that will provide global satellite communications (SATCOM) narrowband connectivity for communications use by the United States at data rates up to 384kbit/s. The program will deliver five satellites, four ground stations, and a terrestrial transport network at a cost of $7.34 billion USD.
The Navy’s Communications Satellite Program Office (PMW 146) of the Program Executive Office (PEO) for Space Systems in San Diego is lead developer for the MUOS Program. Lockheed Martin is the Prime System Contractor and satellite designer for MUOS under U.S Navy Contract N00039-04-C-2009, which was announced September 24, 2004. Key subcontractors include General Dynamics Mission Systems (Ground Transport architecture), Boeing (Legacy UFO and portions of the WCDMA payload) and Harris (deployable mesh reflectors).
The MUOS operates as a global cellular service provider to support the war fighter with modern cell phone-like capabilities, such as multimedia. It converts a commercial third generation (3G) Wideband Code Division Multiple Access (WCDMA) cellular phone system to a military UHF SATCOM radio system using geosynchronous satellites in place of cell towers. By operating in the UHF frequency band, a lower frequency band than that used by conventional terrestrial cellular networks, the MUOS provides warfighters with the tactical ability to communicate in “disadvantaged” environments, such as heavily forested regions where higher frequency signals would be unacceptably attenuated by the forest canopy. The MUOS constellation will consist of four operational satellites and one on-orbit spare. MUOS will provide military point-to-point and netted communication users with precedence-based and pre-emptive access to voice, data, video, or a mixture of voice and data services that span the globe. Connections may be set up on demand by users in the field, within seconds, and then released just as easily, freeing resources for other users. In alignment with more traditional military communications methods, pre-planned networks can also be established either permanently or per specific schedule using the MUOS’ ground-based Network Management Center.
In addition to the cellular MUOS WCDMA payload, a fully capable and separate UFO legacy payload is incorporated into each satellite. The “Legacy” payload extends the useful life of legacy UHF SATCOM terminals and enables a smoother transition to MUOS.”
“Intelsat 30/DLA-1 and Intelsat 31/DLA-2 are high-power, advanced satellites that will provide Direct-to-Home (DTH) television service in Latin America. The satellites are being built for and will be operated by Intelsat, which will lease a majority of the satellite capacity to DIRECTV Latin America, a leading DTH digital television services operator in Latin America. Using spot-beam frequency reuse and the industry’s best technologies, the Ku-band payloads will greatly expand DTH entertainment offerings in Latin America and provide backup and restoration services. The two satellites are designed based on the flight-proven SSL 1300 platform and are contracted to provide service for a minimum of 15 years. […] The satellites will be co-located with Intelsat’s Galaxy 3C satellite at 95 degrees West.”
“After saying farewell to NASA’s Jeff Williams and the rest of the crew onboard the International Space Station on June 18. Expedition 47 Commander Tim Kopra of NASA, Soyuz Commander Yuri Malenchenko of Roscosmos and Flight Engineer Tim Peake of ESA (European Space Agency) undocked from the ISS for the return trip to Earth. Kopra, Malenchenko and Peake spent 186 days in space aboard the orbital laboratory.
[They] landed safely near the town of Dzhezkazgan, Kazakhstan June 18, hours after leaving the International Space Station in their Soyuz TMA-19M spacecraft.”
“At the International Space Station, Expedition 47 Commander Tim Kopra used the Canadarm2 robotic arm to release the Orbital/ATK Cygnus cargo craft June 14, just hours after it was detached from the station. The spacecraft is loaded with trash and other unneeded items. Cygnus is also serving as a platform for an investigation called the Spacecraft Fire Experiment (SAFFIRE), that will deliberately ignite a fire in an enclosed environment so that instruments can measure flame growth and oxygen usage. This experiment is designed to improve the understanding of fire growth in microgravity and to safeguard future space missions. A group of nanosatellites is also being released from Cygnus which will be deorbited June 22 to send the craft into a destructive re-entry over the Pacific Ocean. Cygnus was launched from the Cape Canaveral Air Force Station in Florida atop an Atlas V rocket March 23, arriving at the station March 26 to deliver tons of experiments and supplies for the station’s residents.”
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