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Ariane-5 Glitch Delays GSAT-10 Launch
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Mars Rover Curiosity Has First Target in Sight
Sept.,
19, 2012 - NASA's newly commissioned Mars rover Curiosity is expected to reach
its first science target on Sept., 21 a pyramid-shaped rock that will be used to
assess how well two of the rover's 10 science instruments complement each
others' measurements. The rock, named for chief systems engineer Jake Matijevic,
who died shortly after the rover’s landing, is about 10 inches tall and 16
inches wide at its base.
"Both of those instruments could make a measurement and there could be
differences because one is measuring at a small scale and one is measuring at a
larger scale," said Curiosity lead scientist John Grotzinger.
"The hope is that we can analyze this rock and then do a cross-comparison between the two instruments -- not to mention that it's just a cool looking rock, sitting out there on the plains with almost pyramidal geometry, so that's kind of fun as well," Grotzinger said.
Curiosity, which landed inside a 96-mile-wide impact basin known as Gale Crater on Aug. 6, is enroute to a patch of terrain where three different kinds of rock intersect.
The science team is making several stops to practice using Curiosity's instruments. The point of the two-year mission is to assess whether the landing site has or ever had the chemical and environmental conditions needed for microbial life. (Source) Related pages: Photo 2
"The hope is that we can analyze this rock and then do a cross-comparison between the two instruments -- not to mention that it's just a cool looking rock, sitting out there on the plains with almost pyramidal geometry, so that's kind of fun as well," Grotzinger said.
Curiosity, which landed inside a 96-mile-wide impact basin known as Gale Crater on Aug. 6, is enroute to a patch of terrain where three different kinds of rock intersect.
The science team is making several stops to practice using Curiosity's instruments. The point of the two-year mission is to assess whether the landing site has or ever had the chemical and environmental conditions needed for microbial life. (Source) Related pages: Photo 2
- Harnessing Solar Energy To Sail To The Stars?
It's interesting when you look back at the history of space exploration and realize that propulsion technology hasn't really changed very much.
The earliest rocket prototypes were nothing more than elaborate versions of weapons used during World War 2 and fireworks used during civil celebrations. Even the Space Shuttle made use of solid rocket fuel technology in its pair of solid rocket boosters. But, with the liquid rocket fuel propulsion in the external tank, this combination has proved to be highly effective and launched hundreds of astronauts into space.The approach works -- albeit not very efficiently -- and to get out of the Earth's gravitational well, it seems for now that the extra punch from exothermic processes is needed.The solar sail concept is simple: any surface exposed to electromagnetic radiation 'feels' a pressure known as radiation pressure and it's this pressure that exerts a tiny pushing force against the surface. If the surface happens to be a spacecraft or part of a spacecraft, it could act against it to provide propulsion through space.The concept of radiation pressure isn't particularly new. The idea was first alluded to by Johannes Kepler in 1610 when he suggested the reason why the tail of a comet points away from the sun was in some waycaused by the sun. Kepler even made reference to using this unknown force for exploration when he wrote in a letter: 'Provide ships or sails adapted to the heavenly breezes, and there will be some who will brave even that void.'
The technique is already being used in space exploration for course corrections and fuel savings. For example, NASA's Mercury MESSENGER probe successfully used solar radiation pressure to make small course corrections during its journey to the innermost planet.
WATCH VIDEO: NASA'S SPACE YACHT
With Ikaros' 27 square meter sail deployed, the full effect of radiation pressure from the sun on the sail produces about 0.0002 pounds of force, that's equal to about 0.1 grams -- less than the average goose feather! The acceleration offered by this method of propulsion is small but over a long period of time, incredible speeds could be reached.
The downside to this mode of transportation is that heavier craft will take longer to accelerate, so larger sails would need to be manufactured. Ikaros' sail was impregnated with solar cells to power the electronic equipment and a matrix of liquid crystals around the outside whose reflectivity could be altered to change the attitude of the spacecraft.
Future missions will take these tests further from the sun. The challenge here is that the further away from the sun you go, the weaker the radiation pressure, so acceleration through interstellar space will be limited. Innovations in laser technology may extend the range of solar sails.
The technology is no doubt in its infancy, but new ideas of rotating solar sails in various configurations show great promise.
In deep space, however, there are alternatives receiving very serious consideration -- such as the "eco-friendly" solar sail.
By 1864, it was accepted that light carried momentum and would exert a pressure on anything it meets. A great demonstration of this can be seen in the Nichols radiometer, which is a sealed bulb with tiny silvered glass mirrors attached by a very thin wire inside the glass. On being exposed to light the mirrors start to rotate, driven by radiation pressure exerted by photons from the bulb filament.To make the most out of radiation pressure for space exploration every bit of solar energy needs to be eked out. For any useful form of propulsion, giant solar sails need to be used and exposed to as much light as possible.
The first interplanetary test of a solar sail was conducted by the Japanese Aerospace Exploration Agency in May 2010 with the launch of Ikaros. This was the first time a solar sail was deployed and tested in space and used as its primary propulsion. NASA also launched the orbital solar sail prototype Nanosail-D in November 2010, successfully completing its mission after 240 days in Earth orbit. Ikaros, on the other hand, continues its journey around the sun after passing Venus in December 2010.
Related pages: NASA's Nanosail-D Released into the Winds of Space; Japan's Solar Sail Photographed in Orbit; Using Fusion to Propel an Interstellar Probe
The first interplanetary test of a solar sail was conducted by the Japanese Aerospace Exploration Agency in May 2010 with the launch of Ikaros. This was the first time a solar sail was deployed and tested in space and used as its primary propulsion. NASA also launched the orbital solar sail prototype Nanosail-D in November 2010, successfully completing its mission after 240 days in Earth orbit. Ikaros, on the other hand, continues its journey around the sun after passing Venus in December 2010.
Related pages: NASA's Nanosail-D Released into the Winds of Space; Japan's Solar Sail Photographed in Orbit; Using Fusion to Propel an Interstellar Probe
- NanoThor Aims to Fling NanoSats into Orbit
Sept.,
18, 2012- Humans can only dream of
having the power of Thor, the Norse-inspired
superhero who can whirl and
throw his hammer at blinding speeds. A NASA-funded plan envisions
rockets using a similar idea to hurl tiny satellites toward other
planets.
The "NanoTHOR" project aims to connect small satellites with upper rocket stages by using miles-long tethers, so that the rocket stages can spin the satellites around like Thor's hammer. NASA awarded the idea $100,000 from its Innovative Advanced Concepts program to begin running computer simulations and figure out a hardware design.
NanoTHOR, whose name derives from the Norse god Thor’s thrown hammer, would enable multiple nanosatellites to be carried as secondary payloads on upper stages launched into GTO to be injected into Earth-escape trajectories by scavenging orbital momentum and propellant from the upper stage. It utilizes a lightweight, re-usable tether to transfer momentum from the rocket stage to the nanosatellite. The use of a rotating tether “multiplies” the rocket’s delta-V by the mass ratio of the stage to the nanosat, enabling it to provide both very-high specific impulse propulsion competitive with the best EP thrusters and short transfer times competitive with chemical rockets. The tether also enables the stage’s orbital momentum to be converted to tether rotational momentum to increase the nanosat toss velocity.
"Using a few tricks, we could get that system spinning so the rocket upper stage could swing the nanosatellite out of Earth's orbit and on to the moon or an interplanetary trajectory," said Robert Hoyt, CEO and chief scientist of Tethers Unlimited Inc. Read More
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The "NanoTHOR" project aims to connect small satellites with upper rocket stages by using miles-long tethers, so that the rocket stages can spin the satellites around like Thor's hammer. NASA awarded the idea $100,000 from its Innovative Advanced Concepts program to begin running computer simulations and figure out a hardware design.
NanoTHOR, whose name derives from the Norse god Thor’s thrown hammer, would enable multiple nanosatellites to be carried as secondary payloads on upper stages launched into GTO to be injected into Earth-escape trajectories by scavenging orbital momentum and propellant from the upper stage. It utilizes a lightweight, re-usable tether to transfer momentum from the rocket stage to the nanosatellite. The use of a rotating tether “multiplies” the rocket’s delta-V by the mass ratio of the stage to the nanosat, enabling it to provide both very-high specific impulse propulsion competitive with the best EP thrusters and short transfer times competitive with chemical rockets. The tether also enables the stage’s orbital momentum to be converted to tether rotational momentum to increase the nanosat toss velocity.
"Using a few tricks, we could get that system spinning so the rocket upper stage could swing the nanosatellite out of Earth's orbit and on to the moon or an interplanetary trajectory," said Robert Hoyt, CEO and chief scientist of Tethers Unlimited Inc. Read More
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German Space Agency Prepares to Capture Errant Satellites
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Investigation into Failed Proton Complete
Sept.,
18, 2012- On September 11, the Failure Review Oversight Board completed its
investigation of the August 6 failure of a Proton-M Breeze-M upper stage. The
board confirmed the root cause of the accident as a manufacturing
defect and approved manufacturer Khrunichev’s corrective action plan.
”This is an opportunity to learn, enhance and improve the overall reliability and processes of our systems,” said acting ILS Vice President and Chief Technical Officer John Palme.
The August 6 failure occurred when a pressurization failure in the Breeze-M fuel line caused its third stage burn to operate seven seconds instead of the intended 18 minutes and five seconds. No action has been taken with respect to the Telkom and Ekpress-MD2 satellites that were stranded as a result. On August 7, the investigation board was convened headed by research center TsNIIMash first deputy director O.P. Skorobogatov, scheduled to conclude its work by August 16. As that date came and passed, conflicting political voices alternately threatened mass punishment for the industry’s slackness and denied any sort of systemic problem in Russia’s space industry. The failure came almost exactly one year after another Breeze-M failure that resulted in the Ekspress-AM4 satellite being placed in a useless orbit.
The batch of Breeze-Ms manufactured with the failed unit have already been recalled and are slated to be reworked and inspected. The review board approved that approach and called for an enhanced quality management system to be applied across all Khrunichev facilities. These actions must be completed prior to Proton’s return to flight. The next launch of the vehicle is currently scheduled for mid-October, when it is due to carry an Intelsat satellite into orbit. A reorganization of the industry is in the works that is expected to take place over the next three years. A $21 billion funding allocation was announced by Prime Minister Dmitry Medvedev on September 10 help get the Russian agency back on its feet.
Over the course of recent Russian space failures, the consistent attributions that arise are a critical funding shortage and a more critical workforce shortage. Roscosmos’s 200 employees have an average age of 50, an age which continues to rise as younger professionals have not been hired in sufficient numbers or trained to take their places.
”This is an opportunity to learn, enhance and improve the overall reliability and processes of our systems,” said acting ILS Vice President and Chief Technical Officer John Palme.
The August 6 failure occurred when a pressurization failure in the Breeze-M fuel line caused its third stage burn to operate seven seconds instead of the intended 18 minutes and five seconds. No action has been taken with respect to the Telkom and Ekpress-MD2 satellites that were stranded as a result. On August 7, the investigation board was convened headed by research center TsNIIMash first deputy director O.P. Skorobogatov, scheduled to conclude its work by August 16. As that date came and passed, conflicting political voices alternately threatened mass punishment for the industry’s slackness and denied any sort of systemic problem in Russia’s space industry. The failure came almost exactly one year after another Breeze-M failure that resulted in the Ekspress-AM4 satellite being placed in a useless orbit.
The batch of Breeze-Ms manufactured with the failed unit have already been recalled and are slated to be reworked and inspected. The review board approved that approach and called for an enhanced quality management system to be applied across all Khrunichev facilities. These actions must be completed prior to Proton’s return to flight. The next launch of the vehicle is currently scheduled for mid-October, when it is due to carry an Intelsat satellite into orbit. A reorganization of the industry is in the works that is expected to take place over the next three years. A $21 billion funding allocation was announced by Prime Minister Dmitry Medvedev on September 10 help get the Russian agency back on its feet.
Over the course of recent Russian space failures, the consistent attributions that arise are a critical funding shortage and a more critical workforce shortage. Roscosmos’s 200 employees have an average age of 50, an age which continues to rise as younger professionals have not been hired in sufficient numbers or trained to take their places.
- Two Potentially Hazardous Asteroids Whizz By Earth
Sept.,
14, 2012 - On the evening of September 13-14, two asteroids classified as
“Potentially Hazardous” streaked past Earth with no potential of impacting
the planet. Asteroid 2012 QC8, with a diameter of one kilometer, passed at 23
lunar distances (8.7 million km). Asteroid 2012 QG42, with dimensions of 190-430
meters, passed within 7.5 lunar distances at 2.8 million km. View a Video
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European Industry Develops Space Safety Radar
ESA
will boost European industrial expertise by developing a new radar as part of
the Agency’s Space Situational Awareness programme. The radar will test future
debris monitoring techniques, helping European satellite operators avoid space
hazards and increase safety in Earth orbit.ESA and France’s ONERA – Office National d’Etudes et Recherches Aérospatiales – research centre have signed a €4 million contract that will see the French organisation and five industrial partners in France, Spain and Switzerland design a test surveillance radar and develop a demonstrator model. Work begins this month.
“The agreement significantly increases European industrial competitiveness and capabilities in this field,” says Nicolas Bobrinsky, Head of ESA’s Space Situational Awareness (SSA) Preparatory Programme. Read More
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