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Commercial spaceflight took another step forward this past Sunday, 10 October 2010. Virgin Galactic’s SpaceShipTwo, named Enterprise, was dropped from its mother ship at 45,000 feet and successfully completed maneuvers and landing at the test facilities in the Mojave Desert. Enterprise is designed to carry two pilots and six passengers to an altitude of over 100 kilometers. Sir Richard Branson, founder of Virgin Group, who was present during the first successful flight, commented that “This was one of the most exciting days in the whole history of Virgin. The flight was designed to test the release mechanics from the mother ship and then verify the handling and stall characteristics as well as the lift to drag ratio. A complete set of landing maneuvers were executed at a high altitude, and the ship then made its final descent and landing. Scaled Composites pilot, Pete Siebold, said “The VSS Enterprise was a real joy to fly, especially when one considers the fact that the vehicle has been designed not only to be a Mach 3.5 spaceship capable of going into space but also one of the worlds highest altitude gliders.” Virgin Galactic will continue testing the new rocket ship during the coming year, and expects to fly its first commercial passengers within 18 months. George Whitesides, former Executive Director of the National Space Society and current CEO of Virgin Galactic, was also present at the historic flight. Whitesides said, “To see the world’s first manned commercial spaceship landing on a runway is a sight I always dreamed I would behold. Now, our challenge going forward will be to complete our experimental program, obtain our FAA license and safely bring the system into service at Spaceport America, New Mexico.” |
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Archive for the ‘Dave Fischer’ Category
Virgin Galactic - First Free Flight
Monday, October 11th, 2010
The Wilkinson Microwave Anisotropy Probe
Saturday, October 9th, 2010|
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Scientists announced this week that the mission of the Wilkinson Microwave Anisotropy Probe (WMAP) has been completed. The last set of observations were downloaded on 20 August 2010, and researchers are compiling the final results. The satellite was placed in a permanent parking orbit around the sun on 8 September 2010. WMAP was launched on 30 June 2001 and placed into an orbit around SEL-2, the second Sun-Earth Lagrange point. SEL-2 lies 1,500,000 kilometers beyond the Earth on a line from the Sun to the Earth. WMAP was the first spacecraft to occupy this location. SEL-2 is extremely cold, shaded from the Sun’s activity by the Earth’s shadow and ideal as an astronomical location in space. In 2009, the Herschel Space Observatory and Planck space observatory took up residence at SEL-2. They will be joined in 2014 or 2015 by the James Webb Space Telescope. First detected in 1964, the cosmic microwave background (CMB) radiation (television “snow” - before cable), is the remnants of the extremely hot radiation from the big-bang, now cooled to almost absolute zero after 13.73 billions years of the expansion of the universe. It is a pattern frozen in place when the cosmos was only 380,000 years old. WMAP The Planck observatory is currently making high resolution measurements of both the total intensity and polarization of the primordial CMB anisotropies that were first observed by COBE and WMAP. The observations made by WMAP are the most accurate to date and have allowed scientists to rule out several “inflation” models about what happened in the first trillionths of a second during the birth of the cosmos, while supplying support for several other models:
Dark energy is the force driving the galaxies in the universe apart at an ever increasing rate. At some point in the future, inhabitants of the Milky Way will not be able to see any other objects in the sky. These entities will conclude that they are at the center of the universe, and will have no information about the big bang and the creation of the cosmos as we know it today. |
The Astronomy and Astrophysics Decadal Survey - 2012 to 2021
Thursday, September 16th, 2010|
by Dave Fischer The National Research Council has released Its sixth decadal survey of astronomy and astrophysics. The plan focuses on three science objectives:
The report addresses large, medium, and small activities in these fields. It surveys the existing facilities and the new facilities that would be needed, both ground based and space based. It looks at the known science objectives and where new discoveries might be made. And it looks at the promise of the proposals and the risks associated with each. The large scale space-based projects are:
WFIRST, the near infrared wide-field telescope, is intended to explore Dark Energy and Exoplanet statistics as well as support guest survey investigations. The Explorer Program is ongoing and funds rapid, targeted projects that deliver a high science return. Past projects include WMAP, Swift, GALEX and WISE. LISA will exploit the new field of astronomy using long wavelength gravitational radiation measured by three spacecraft 5 million kilometers apart. IXO is a large area, high spectral resolution x-ray observatory to explore hottest regions in the universe, including clusters of galaxies, the intergalactic medium, and black hole accretion disks. The medium scale space-based projects are:
The New Worlds technology development program is a research program to obtain preliminary observations in order to study nearby habitable planets. Included is technology development in order to make an informed decision in the second half of this decade on a flagship mission. The Inflation Technology development program will use ground based microwave background telescopes to examine “B-mode polarization.” This is a sensitive signature of processes thought to have occurred during the earliest moments of the universe. If a signal is seen, then a space-based mission with at least ten times greater sensitivity is warranted and associated technology development would be needed. There are four large scale ground-based projects recommended, and prioritized as follows:
The LSST project would address research such as dark energy using gravitational lensing, dark matter, Near-Earth Kuiper-belt objects, the Solar neighborhood, and transient phenomena such as gamma-ray bursts, variable stars, and supernova. The mid-scale program would fund annual proposals to compete for funding, of which around 7 proposals would be chosen during the decade. The Giant Segmented Mirror Telescope project suggests that NSF chose one of the two current 30 meter telescope projects (The Giant Magellan Telescope in Chile or the Thirty Meter Telescope in Hawaii) and invest in a quarter share in order to provide access for the entire US community. The report proposes that the team responsible for the proposed US Advanced Gamma-ray Imaging System (AGIS) collaborate as a minor partner with the European Cherenkov Telescope Array (CTA). There is one medium scale ground-based program that was recommended by the NRC Decadal Survey:
This 25 meter wide-field sub-millimeter telescope would work in conjunction with the Atacama Large Millimeter Array (ALMA) in Chile. The small scale investment recommendations are:
Other documentation: Town Hall Slides (pdf). |
JWST - The James Webb Space Telescope
Wednesday, September 8th, 2010|
by Dave Fischer
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The James Webb Space Telescope (JWST) is an infrared observatory, and a partial successor to the Hubble Space Telescope. JWST does not view visible light because light from the earliest universe has shifted toward the infrared (red shift). Infrared sensitivity is required in order to see further back in time toward the beginning of the universe than either Hubble or ground based observatories.The James Webb Space Telescope is a joint venture between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA). In all, fifteen countries are making contributions to JWST. The are four main components to the scientific mission:
JWST is scheduled for launch in 2014 aboard an Ariane 5 rocket. It will take up residence at the Sun-Earth Lagrange point 2 (SEL-2). SEL-2 is 1,500,000 km beyond the Earth from the Sun (the Earth-Moon L2 is only 61,500 km beyond the Moon). The location was chosen in order to be able to shield the telescope from the infrared radiation of the Sun and the Earth. |
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Currently, SEL-2 is occupied by the Wilkinson Microwave Anisotropy Probe (WMAP), which was launched 30 June 2001, and the Herschel and Planck observatories, which were launched together on an Ariane 5 on 14 May 2009. The image at left is a cutaway diagram the the Ariane 5 rocket, illustrating how the JWST will fold up inside the payload fairing. With the large screen behind it, the JWST will be about 21 m in width. It will stand about three stories high. The main telescope mirror, which measures 6.5 m in diameter, is too large to launch in one piece. Instead, it consists of 17 individual mirror segments mounted on a frame which will be folded inside the fairing of the Ariane 5 at launch. Once it arrives at SEL-2, it will unfold, as this animation shows. There are four instruments in the Integrated Science Instrument Module designed to conduct the investigations on board the James Webb Space Telescope: |
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The image below shows the locations of the four instruments in the Integrated Science Instrument Module (ISIM). Below, the image shows the location of the instrument package within the JWST.
The Mid-Infrared Instrument (MIRI) is an imager/spectrograph that covers the wavelength range of 5 to 27 micrometers. The camera provides wide-field broadband imagery, and the spectrograph module provides medium-resolution spectroscopy over a smaller field of view compared to the imager. The nominal operating temperature for the MIRI is 7K. Additional information can be found at the MIRI website, Space Telescope Science Institute. The Near Infrared Camera (NIRCam) is an imager with a large field of view and high angular resolution. The NIRCam covers a wavelength range of 0.6 to 5 micrometers. More on NIRCam. The Near Infrared Spectrograph (NIRSpec) measures the simultaneous spectra of more than 100 objects in a 9-square-arcminute field of view. This instrument provides medium-resolution spectroscopy over a wavelength range of 1 to 5 micrometers and lower-resolution spectroscopy from 0.6 to 5 micrometers. See the Space Telescope Science Institute information on NIRSpec. The Fine Guidance Sensor (FGS) sensor is used for both “guide star” acquisition and fine pointing. See information from the Space Telescope Science Institute about NIRSpec. |
See also:
The Wikipedia article on JWST.
NASA home page for JWST.
ESA home page for JWST.
CSA home page for JWST.
Make your own Paper Model of the JWST.
YouTube and JWST.
Let us know what you think. What do you want to know about? Post a comment.
Desert RATS
Friday, September 3rd, 2010|
by Dave Fischer If you want humanity to explore the Solar System, you have to test the systems you plan to use for moving around and living. And where is there a readily available harsh environment for such testing? Arizona. In the Summer it is hot and dry. In the Winter it is cold and dry (or wet, depending on the state of the Arctic storm systems). Currently underway (31 August through 15 September) is the 13th iteration of the Desert RATS program. You can follow their exploits on the RATS’ Blog. |
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NASA’s Research and Technology Studies (RATS) program is designed to gather engineers, astronauts and scientists and test technology. This year, the major objectives include:
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Let us know what you think. What do you want to know about? Post a comment.
CRuSR
Wednesday, September 1st, 2010|
by Dave Fischer Commercial Reusable Suborbital Research Program NASA has awarded $475,000 as part of its program to development recoverable launch vehicles to be used for small payloads going to “near-space,” the region of Earth’s atmosphere between 65,000 and 350,000 feet. The awards were made under the CRuSR program (Commercial Reusable Suborbital Research Program). NASA’s press release states:
The awards were made to Armadillo Aerospace, home to the Super-Mod vehicle, and Masten Space Systems, home to the Xaero vehicle. Armadillo will fly three missions from Spaceport America in New Mexico. Two are schedule for an altitude of nine miles each, and the third is scheduled for 25 miles (132,000 feet - 40,200 meters). Masten will fly four missions this winter from the Mojave Spaceport in California. Two of the flights are slated for three miles and two are slated for 18 miles (95,000 feet - 29,000 meters). |
 Image Credit: Armadillo Aerospace |
 Image Credit: Masten Space Systems |
Let us know what you think. What do you want to know about? Post a comment.
1959 - Twelve Men On The Moon
Friday, August 27th, 2010|
by Dave Fischer
The Lunar Reconnaissance Orbiter Camera team recently released this image featuring the famous crater Copernicus with its ejecta splashed across much of the face of the Moon. Copernicus and the crater Eratosthenes lie just south of Mare Imbrium. To the east of Copernicus and south of Eratosthenes lies the nearly featureless plain called Sinus Aestuum. Here, just southeast of Eratosthenes lies the location of a proposed Moon Base. In addition to the scientific value of this area, the rich ores of the Rima Bode regional dark mantling deposit lie nearby. |
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On 20 March 1959, Arthur G. Trudeau, Chief of Research and Development for the U.S. Army, submitted a request for the study to place a lunar outpost on the Moon. The result was Project Horizon, a plan (dated 9 June 1959) to place a military base with 10-20 men on the surface of the Moon by 1965. Full details are in Vol. I and Vol. II (pdf). The introduction to the proposal stated that the establishment of a lunar base would:
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It further stated the following, prescient about the Soviet manned capability, but extremely optimistic about the timetable for the Moon Base:
Underlying all of this was the traditional von Braun team approach:
The proposal discusses the ongoing development of the Saturn I by ARPA, expecting it would be fully operational by 1963. The Saturn I stood more than 200 feet tall, and would be superseded by the Saturn II in 1964, standing 304 feet tall. By the end of 1964, a total of 72 Saturn I rockets would have been launched on various programs of discovery, including 40 to support the manned lunar base. In order to support the full complement of 12 men, 61 Saturn I and 88 Saturn II launches would be required by the end of 1966, landing 490,000 pounds of cargo on the lunar surface. 64 launches were scheduled for 1967, landing an additional 266,000 pounds of supplies. The total cost of the eight and one-half year program was estimated to be $6 Billion. The von Braun team thought very large indeed. |
Let us know what you think. What do you want to know about? Post a comment.
Pintle Injector Rocket Engines
Sunday, August 1st, 2010|
by Dave Fischer We have had several queries concerning “pintle injectors” (make sure you read the last paragraph of this post), as these are mentioned in the Space-X page on the Falcon 9, where it refers to the Merlin rocket engine and the “pintle style injector“:
Based on the queries and the Space-X information, we went sleuthing. First, we came across the fact that TRW built the LEM descent engine, which used the pintle injector. We ran across David Meerman Scott’s blog apolloartifacts for a discussion and look at a model of the famous Lunar Module Descent Engine (LMDE). The engine was made famous by the Apollo 13 mission, where:
In 2000, TRW demonstrated the TR-106 engine (pintle injector) using LOX / LH2 at NASA’s John C. Stennis Space Center . The engine generated 650,000 pounds of thrust, more than the 400,000 pounds of thrust generated by the Space Shuttle Main Engine SSME. Al Frew, vice president and general manager, TRW Space & Technology Division stated:
Despite the promise the motor demonstrated, NASA canceled further work. The pintle injector engines have a long history in the former Soviet Union. The NK-33 was the successor to the NK-15 engines used in the failed Soviet N1 Moon launcher. NK-33 have been used with the Russian Proton launch system. An interesting discussion of the Soviet Moon rocket, its engines and the NK-33 successor can be found here, along with spectacular video of the launch and explosion. Orbital Sciences has now contracted with Aerojet (owner of the NK-33 engines) to finish developing and testing the NK-33 engines, now designated as AJ26-58 for the Taurus II. |
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Jonathon Goff, at Masten Space Systems, had a commentary at Selenianboondocks on the 2006 Space-X change from an ablative Merlin engine to a regenerative engine. Jon states that the “engine related problems are interrelated, and that they have to do with the combination of using a high chamber pressure engine design with a pintle-injector and an ablatively cooled chamber wall.” That is, the flame produced by the cone of fuel and oxidizer hits the wall of the chamber and overheats the wall. Included in the commentary is a simplified image of a pintle injector rocket engine, which illustrates the flow of liquid oxygen and fuel (RP-1 or liquid hydrogen) through the pintle injector into a cone shaped spray in the combustion chamber. The replacement of the ablative chamber with a regenerative chamber eliminates the overheating. |
 Pintle Injector Image Credit: Forschungsgruppe Alternative Raumfahrtkonzepte |
Below left is the business end of the LEM Descent engine, showing the Pintle Injector:
Below right is an image by Warren W. Thompson at the unveiling of Space-X’s Falcon 1 at the Air & Space Museum on 4 December 2003.
 Lunar Module Descent Engine Image Credit: jurvetson on Flickr |
 Merlin Engine with Pintle Injector Image Credit: Warren W. Thompson |
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Finally, while explaining the Pintle Injector to a friend, I realized that almost everybody who has a garden or tends a lawn has personal experience with pintles. You all use a nozzle on the end of your watering hose. Crank it down and you get a steady, narrow stream of water shooting out in a long arc. Crank it back the other way when you want to shut it off, and you get a wide, cone shaped fan spray. Now, turn off the water and look at the business end of the garden hose nozzle (please shut the water off first). There in the middle is a round pintle that moves back and forth as you crank the outer casing one way or the other. And the fan shaped spray of water with which you are familiar is what the fuel and oxidizer spray looks like inside the rocket engine. So take another look at the two images above and imagine the fan shaped spray. The only difference is that your spray of water doesn’t explosively combust and throw a rocket into space. |