NASA to Explore 'Secret Layer' of the Sun

Zeeman splitting of spectral lines from a strongly-magnetized sunspot.

Click here to enlarge image

Next April, for a grand total of 8 minutes, NASA astronomers are going to glimpse a secret layer of the sun.

Researchers call it "the transition region." It is a place in the sun's atmosphere, about 5000 km above the stellar surface, where magnetic fields overwhelm the pressure of matter and seize control of the sun's gases. It's where solar flares explode, where coronal mass ejections begin their journey to Earth, where the solar wind is mysteriously accelerated to a million mph.
It is, in short, the birthplace of space weather.

Researchers hope it is about to yield its secrets.

"Early next year, we're going to launch an experimental telescope that can measure vector magnetic fields in the transition region," explains Jonathan Cirtain of the Marshall Space Flight Center (MSFC). Previous studies have measured these fields above and below the transition region—but never inside it. "We hope to be the first."

The name of the telescope is SUMI, short for Solar Ultraviolet Magnetograph Investigation. It was developed by astronomers and engineers at the MSFC and is currently scheduled for launch from White Sands, New Mexico, in April 2009.

SUMI works by means of "Zeeman splitting." Dutch physicist Pieter Zeeman discovered the effect in the 19th century. When a glass tube filled with incandescent gas is dipped into a magnetic field, spectral lines emitted by the gas get split into two slightly different colors—the stronger the field, the bigger the splitting. The same thing happens on the sun. Here, for instance, are some spectral lines from gaseous iron being split by the magnetic field of a sunspot (see image above).

By measuring the gap, astronomers estimate the strength of the sunspot's magnetic field. Furthermore, by measuring the polarization of the split line, astronomers can figure out the direction of the magnetic field. Strength + direction = everything you ever wanted to know about a magnetic field!

This trick has been applied to thousands of sunspots on the solar surface, but never to the transition region just a short distance above.
Why not?

"Just bad luck, really," says Cirtain. "Gas in the transition region doesn't produce many strong spectral lines that we can see at visible wavelengths." It does, however, produce lines at UV wavelengths invisible from Earth's surface.

"That's why we have to leave Earth."

SUMI will blast off inside the nose cone of a Black Brant rocket on a sub-orbital flight that takes it to an altitude of 300 km. "We'll be above more than 99.99% of Earth's atmosphere," says Cirtain. About 68 seconds into the flight, payload doors will open, affording SUMI a crystal-clear view of the UV sun. "From that moment, we've only got 8 minutes to work with. We'll target an active region and start taking data."

SUMI's "vector magnetograph" is tuned to study a pair of spectral lines: one from triply-ionized carbon (CIV) at 155 nanometers and a second from singly-ionized magnesium (MgII) at 280 nanometers. "There's nothing special about those ions," notes Cirtain. "They just happen to produce the best and brightest lines at temperatures and densities typical of the transition region."

Cirtain anticipates how it will feel to have his precious instrument hurtling 300 km above Earth at 5,000 mph: "Eight minutes of terror." He'll start breathing again when the payload doors close and SUMI begins its descent back to Earth. Cirtain ticks off the stages: "Reentry into the atmosphere. Open parachutes. Landing back at White Sands. Recovery."

The short flight probably won't lead to immediate breakthroughs. "But it will demonstrate the SUMI concept and show us if it's going to work." A successful flight would lead to more flights and eventually to a SUMI-style magnetograph permanently installed on a space telescope.

"That's the dream," he says. Transition region, prepare to yield...

Source: Science@NASA, by Dr. Tony Phillips

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'Laser Comb' To Measure the Accelerating Universe

Written by Nancy Atkinson

Back in April, UT published an article about using a device called a 'laser comb' to search for Earth-like planets. But astronomers also hope to use the device to search for dark energy in an ambitious project that would measure the velocities of distant galaxies and quasars over a 20-year period. This would let astronomers test Einstein's theory of general relativity and the nature of the mysterious dark energy. The device uses femto-second (one millionth of one billionth of a second) pulses of laser light coupled with an atomic clock to provide a precise standard for measuring wavelengths of light. Also known as an “astro-comb,” these devices should give astronomers the ability to use the Doppler shift method with incredible precision to measure spectral lines of starlight up to 60 times greater than any current high-tech method. Astronomers have been testing the device, and hope to use one in conjunction with the new Extremely Large Telescope which is being designed by ESO, the European Southern Observatory.

Astronomers use instruments called spectrographs to spread the light from celestial objects into its component colors, or frequencies, in the same way water droplets create a rainbow from sunlight. They can then measure the velocities of stars, galaxies and quasars, search for planets around other stars, or study the expansion of the Universe. A spectrograph must be accurately calibrated so that the frequencies of light can be correctly measured. This is similar to how we need accurate rulers to measure lengths correctly. In the present case, a laser provides a sort of ruler, for measuring colors rather than distances, with an extremely accurate and fine grid.

New, extremely precise spectrographs will be needed in experiments planned for the future Extremely Large Telescope.

"We'll need something beyond what current technology can offer, and that's where the laser frequency comb comes in. It is worth recalling that the kind of precision required, 1 cm/s, corresponds, on the focal plane of a typical high-resolution spectrograph, to a shift of a few tenths of a nanometre, that is, the size of some molecules," explains PhD student and team member Constanza Araujo-Hauck from ESO.

The new calibration technique comes from the combination of astronomy and quantum optics, in a collaboration between researchers at ESO and the Max Planck Institute for Quantum Optics. It uses ultra-short pulses of laser light to create a 'frequency comb' - light at many frequencies separated by a constant interval - to create just the kind of precise 'ruler' needed to calibrate a spectrograph.

The device has been tested on a solar telescope, a new version of the system is now being built for the HARPS planet-finder instrument on ESO's 3.6-metre telescope at La Silla in Chile, before being considered for future generations of instruments.

Original here

LHC by the numbers

The largest particle accelerator in the world, which will feel its first full proton beams tomorrow, just oozes numerical hyperbole.

Geoff Brumfiel

As the world's biggest particle accelerator prepares to crank up its proton beams, Nature rounds up the big numbers behind the mother of all atom smashers.

• 27 kilometres = circumference of the LHC.

• 50 kilometres per hour = speed limit for physicists on site.

The LHC: an endless source of superlatives ...CERN

• 32 minutes = time taken by a law-abiding physicist to circle the ring.

• ~1 billion kilometres per hour (99.9999991% the speed of light) = maximum proton speed around the ring.

• One ten-thousandth of a second = time taken by proton to circle the ring.

• 0.00000000047 grams = total mass of protons circulating in the LHC at any time.

• 362 megajoules = collective energy of LHC's protons at top speed.

The USS Ronald Reagan: certainly hefty, but not quite as energetic as the LHC's protons.US Navy

• 88,000 tonnes = total weight of the aircraft carrier USS Ronald Reagan.

• 361 megajoules = energy of the USS Ronald Regan when cruising at 5.6 knots.

• US$4.1 billion = cost of building the LHC.

• US$4.5 billion = cost of the USS Ronald Regan.

• ~9,000 cubic metres = total volume of the LHC's major vacuum systems.

• 4,650 cubic metres = interior volume of the Big Ben clock tower at Westminster.

• 14 years = time taken to build LHC.

• 13 years = time taken to build Big Ben.

The clock tower at the Palace of Westminster: big, but only half the size of the LHC's tubes.punchstock

• ~6 million = number of DVDs needed to hold all of the data generated by the LHC.

• 6.9 kilometres = height of 4 million DVDs stacked on top of each other.

• 4.8 kilometres = height of Mount Blanc.

• 0.75 grams = amount of hydrogen needed to fill a party balloon.

• 0.000000002 grams = amount of hydrogen consumed each day by the LHC.

• ~1 million years = time needed for the LHC to use one party balloon's worth of hydrogen.

• 10^-13 atmospheres = vacuum of the LHC's beamline.

• 10^-12 atmospheres = atmospheric pressure on the Moon.

• 8.3 tesla = top field strength of each of the LHC's 1232 superconducting dipole magnets.

• 1 tesla = strength of a typical scrapyard electromagnet.

Original here

Darwin & Paleontology: 50 years of conflict

by Brian Switek

Brian Switek is an ecology & evolution student at Rutgers University.

"... for in all the boundless realm of philosophy and science no thought has brought with it so much pain, or in the end has led to such a full measure of the joy which comes of intellectual effort and activity as that doctrine of Organic Evolution which will ever be associated, first and foremost, with the name of Charles Robert Darwin." - Edward Poulton, "Fifty Years of Darwinism" (1908)

Edward Poulton and T.C. Chamberlin may have been impressed by evolution by natural selection during the centenary celebration of Charles Darwin's (portrait on the lower right) birth in 1908, but paleontologist H.F. Osborn (see photo below) was not as enthusiastic. To commemorate Darwin's achievements, primarily On the Origin of Species, a series of lectures were organized by the American Association for the Advancement of Science which were later collected in the book Fifty Years of Darwinism. While Chamberlin and Poulton championed evolution by natural selection as triumphant over the "fad" of Neo-Lamarckism that had cropped up in the wake of Darwin's work, other contributors felt that Darwin's theory was not adequate to explain evolutionary change. Osborn was one of them, and although he had mostly abandoned the concept of acquired characteristics, he latched onto an adapted form of Lamarck's "complexifying force" in the form of orthogenesis. He laid out this program in his contribution on paleontology and Darwin's theory.

As I have written about before, paleontology was a problem for Darwin. The succession of life in the geologic strata was not inconsistent with his theory of evolution, yet the fossil record did not offer the minutely-graded transitional forms his theory predicted. (T.H. Huxley would later propose at least three major evolutionary transitions during the 1870's, but even he had to admit that many of the fossils represented only approximations of expected transitional forms. Huxley concluded that the actual line of descent for two of those transitions, terrestrial carnivorous mammals to whales and reptiles to birds, had yet to be found. The recent evolution of the one-toed horse from three-toed ancestors was a better example of a direct line.) Even beyond the conceptual issues, some of the most vociferous opponents of Darwin's theory were paleontologists and geologists. In 1860 Darwin wrote to the father of American paleontology, Joseph Leidy, complaining;

Most paleontologists (with some few good exceptions) entirely despise my work... all the older geologists with the one exception of Lyell, whom I look at as a host in himself, are even more vehement against the modification of species than are even the paleontologists.

In the face of such opposition, Darwin was primarily concerned with getting other workers to at least partially accept his conclusions. As he acknowledged in the letter to Leidy, he was sure that some of his ideas would turn out to be false, but he was sure that the core of evolution by natural selection was correct. In terms of paleontology, this would require a new type of program that specifically tried to identify transitions in the fossil record.

In Osborn's view, "Darwinian paleontology" did not really start until 1868 when German paleontologist W.H. Waagen described evolutionary changes in ammonites, or the coiled shells of ancient cephalopods. Yet Waagen's was not truly a Darwinian view. According to Peter Bowler's historical review The Eclipse of Darwinism, Waagen viewed ammonites as a group that underwent a kind of senescence in which they degenerated and became extinct because of mutations. (Although it would have been unknown to Waagen, the weird form Nipponites is a good example of the baffling arrangements seen in the later ammonites. These forms have long vexed paleontologists, as many seem to be caught in the act of uncoiling or becoming tangled up in their own shells.) Thus ammonites were not examples of evolution due to natural selection working on variation; there were internal forces involved that pushed groups to evolve and eventually to "over-evolve" particular traits to the point where they became extinct.

Even if the theories of change did not fit, Waagen at least tried to form an evolutionary sequence. Such quests were initially inspired by Darwin's work. Osborn compared Darwin to Moses, leading researchers to the Paleontological Promised Land but never entering it. Darwin had set paleontologists in search of lines of descent in the fossil record. As more strata were mined for fossils, particularly in America, the results clearly showed that evolution had occurred. Darwin was right, but Osborn only thought he was correct in the general sense.

Osborn thought that natural selection had an important role to play in nature; it acted as a discriminating force tied to extinction. As evidence of this Osborn suggested that a particular pattern of grinding teeth independently possessed by North American herbivores during the Oligocene and Miocene (spanning from about 34 million years ago to about 5 million years ago) all led them to extinction. Indeed, selection was primarily a destructive force. Beyond that, it appeared to account for little.

In terms of gradual changes seen in the fossil record (i.e. the gradual lengthening of the neck of the giraffe), Osborn stated that there was no evidence of natural selection. What's more, he defied the implications of Dollo's Law (namely that what has already evolved dictates what can evolve, therefore preventing exact evolutionary reversal; there's no going backwards), and stated that the conditions of ancestors do not dictate future evolution. Speaking specifically in terms of the proportions of the skull and foot, Osborn asserted that with each generation the creatures were free to evolve in any particular direction. Indeed, he may have made concessions to Darwin in the introduction, but it was not long before the truth came out;

In all the research since 1869 on the transformations observed in closely successive phyletic series no evidence whatever, to my knowledge, has been brought forward by any paleontologist, either of the vertebrated or invertebrated animals, that the fit originates by selection from the fortuitous.

For Osborn the core of evolution had little to do with chance. The driving force of transmutation was some unknown internal growth force. What's more, whatever this internal driving force may have been it was too slow to be observed in anything but the fossil record. Time made all the difference, and if variations meant little for evolution then there had to be something else pushing creatures forward;

The law of gradual appearance or origin of many new characters in definite or determinate directions from the very beginning I regard as the grandest contribution which paleontology has made to evolution.

Yet Osborn still had to recognize the role of adaptation. Just how had the important traits that allowed creatures to occupy a particular niche or have a certain mode of life arise? Osborn proposed that some internal directing force caused the emergence of new structures that were already adaptive when they arose. He called these "rectigradations";

... the law of gradual change in certain determinate, definite, and at least in some cases adaptive directions, through very long periods of time, and the absence of chance or non-direction in the origin of a large number of adaptive and other new characters, is the common working principle both in vertebrate and invertebrate paleontology.

Perhaps most shocking of all, Osborn asserted that Darwin was on the path to coming to a similar view of evolution;

Here we find ourselves expanding a principle which was clearly foreshadowed by Darwin, and which, had he pursued it to its logical sequence, would have brought him to orthogenesis, namely, that variations may not be without direction, but that law may lie among the hidden recesses of the nature of the organism; in other words, Darwin himself frequently professed ignorance of the laws of variation as well as the belief that such laws might be discovered.

Perhaps this was a bit of wishful thinking on Osborn's part (if he was right it would make him an important heir to Darwin's evolutionary legacy), and I do not think that Darwin would have come around to Osborn's view. The reason for this has to do with the way each researcher viewed nature, which is somewhat reminiscent of the debates between the French naturalists Geoffroy St. Hilaire (an evolutionist) and Georges Cuvier (an anti-evolutionist, painting on the left). (See The Cuvier-Geoffroy Debate for a historical analysis.) Although their arguments have commonly been construed to center on evolution, the basis of their debate hinged on different ways of understanding nature. Geoffroy had a focus on the emergence of form, primarily through development, while Cuvier was concerned with adaptation. (This may seem strange as we often associate the term "adaptation" with evolution, but before Darwin adaptation was often discussed in terms of how the Designer had perfectly adapted organisms to their habitats. Darwin turned this on its head by throwing out the designer and showing that natural selection could act as a directing force.) Adaptation caused by natural selection on fortuitous variations was key for Darwin while Osborn's view has more to do with potentially unknowable internal forces. It was the difference between evolution being driven from within (Osborn) or without (Darwin).

Osborn closed his contribution by quoting Aristotle, presuming that there is some unknown (or unknowable) law that gave purpose to structures. Teeth are for eating and eyes are for seeing, after all; how could chance variations ever produce such adaptive structures? Other paleontologists might have shied away from such views, but Osborn was one of the most prominent voices for paleontology during the first quarter of the 20th century. What he said has often been taken as an indicator for the state of paleontology during the time when he lived (which may not be true; we need more historical scholarship).

Whether paleontologists agreed with Osborn or not, pioneering lab work in genetics made field work and paleontology seem anachronistic. While workers in labs were slowly reviving natural selection, a few prominent paleontologists preferred orthogenic trends. This likely contributed to the divide between the "field sciences" and "lab sciences" in biology, and by the time G.G. Simpson published his major synthetic work Tempo and Mode in Evolution in the 1940's, he had to mention the tendency of geneticists and paleontologists to dismiss each others work.

Just as it had been in other areas of science, non-Darwinian mechanisms of evolution were eventually booted out of paleontology. Simpson's work marked a sea change in which natural selection and the fossil record were married together. Indeed, natural selection was successfully revived as the primary mechanism of evolution in all areas of biology. Yet I am still curious about the time between the publication of On the Origin and Tempo and Mode. Why did orthogenesis hang on for so long? Proponents of the concept in paleontology certainly thought they had a viable scientific alternative, yet I am sure that social factors (particularly in Osborn's case) made it an attractive hypothesis. Osborn might have loudly proclaimed his notions from the AMNH, but what did other paleontologists think? I don't have any answers (Osborn is a lightening rod for historical study), but I think the area is ripe with research opportunities. We really do need a history of paleontology from 1870-1940.

Original here

Dryden Aircraft Photo Collection

This collection contains digitized photos of many of the unique research aircraft flown at NASA Dryden Flight Research Center
at Edwards, California. These images date from the 1940s to the present. No copyright protection is asserted for these photographs. See Using NASA Imagery and Linking to NASA Web Sites for more information. Multiple resolutions are available. All are 24-bit color JPEGs. The FAQ will answer some frequently asked questions.

Dryden Aircraft Slideshow feature the best photos of various aircraft. What's New lists photos recently added to the collection.

Aircraft		Research Program	Flight Dates	#Images
A-5A Vigilante (Historical)		SST & Sonic Boom Research	1963	1
Active Aeroelastic Wing (AAW) (Historical)		Active Aeroelastic Wing Research	2001 - present	25
AD-1 (Historical)		Oblique Wing Research	1979 - 1982	7
Aero-Commander (Historical)		Unswept Fuselage Study	1968	2
Aerospike Rocket Test		First know data from a solid fueled aerospike rocket in flight	Present	3
Altair		Remotely operated, uninhabited aircraft program	Present	24
Altus (Historical)		ERAST Program - High Altitude Unmanned Aerial Vehicle	1996 - 1997	10
Apex (Historical)		ERAST Program - High Altitude Sailplane	1995 - 1998	3
APV-3 NUAVT (Historical)		Auto Piloted Vehicle (APV-3) Networked Unmanned Aerial Vehicle	2005	3
Autonomous Aerial Refueling (AAR) (Historical)		F/A-18 #845 Autonomous Aerial Refueling (AAR) project	2002 - 2003	10
Autonomous Airborne Refueling Demonstration (AARD)		F/A-18 #845 Autonomous Airborne Refueling	2006 - present	12
Autonomous Formation Flight (AFF) (Historical)		Autonomous Formation Flight Control	2000 - 2001	8
Autonomous Soaring Project		Thermal Lift Tests to Extend UAV Flight Range and Endurance	2005	3
B-29 Superfortress (Historical)		Air Drop Mothership	1940s - 1960s	10
B-47A Stratojet (Historical)		Landing Drag Chute Study and Dynamic Response Research	1953 - 1957	7
B-52 Stratofortress		Air Drop Mothership (Historical)	1959 - 2004	44
		F-111 Chute Drop Test (Historical)	1989	2
		HiMAT Mothership (Historical)	1979 - 1983	2
		Shuttle Solid Rocket Booster (Historical)	1970s - 1980s	6
		STS Drag Chute Tests (Historical)	1990 - 1991	5
		X-38 Mothership (Historical)	1997 - 2000	11
B-57B Canberra (Historical)		Atmospheric Research	1982	3
Bell 47 (Historical)		Support and LLRV Chase/Training	early 1960s - 1985	3
Boeing 720 (Historical)		CID - Controlled Impact Demonstration	1984	7
Boeing 727 (Historical)		Vortex study	1974	1
Boeing 747 (Historical)		Vortex study	1974, 1979	4
C-17 Globemaster III		Propulsion Health Management (PHM)	2003 - present	11
C-140 Jetstar (Historical)		General purpose airborne simulator	1963 - 1988	5
C-141A (Historical)		Eclipse tow aircraft	1997	1
Centurion (Historical)		High Altitude Solar Powered Aircraft	1997	30
CV-990 (Historical)		LSRA - Landing Systems Research Aircraft	1993 - 1996	17
D-558-1 Skystreak (Historical)		Transonic Flight Research	1947 - 1953	11
D-558-2 Skyrocket (Historical)		Transonic and Supersonic Flight Research	1949 - 1956	18
Daedalus (Historical)		Human Powered Aircraft	1987 - 1988	2
DC-8		Airborne Laboratory	1997 - present	129
Demonstrator 2 (Historical)		ERAST Research	1996	1
E-2C Hawkeye		Loads Lab weight tests for planned modifications	2005	3
Eclipse (Historical)		Towed aircraft launch	1997	16
ER-2		High altitude Research	1997 - present	34
F-4A Phantom (Historical)		Navy fighter	1965	1
F-4C Phantom II (Historical)		Air flow tests	1984	2
F4D Skyray (Historical)		N/A	1950s	1
F5D-1 Skylancer (Historical)		Develop Dyna-soar launch pad abort procedures	1961 - 1970	6
F-8A Crusader (Historical)		SCW - Supercritical Wing	1971 - 1973	7
F-8C Crusader (Historical)		DFBW - Digital Fly-By-Wire	1972 - 1985	8
F-14 Tomcat (Historical)		Variable Sweep Transition flight experiment	1986 - 1987	8
F-15 Eagle		F-15B SBRDC/ECANS	2007 - present	7
		F-15B #837 Intelligent Flight Control System	2002 - present	9
		F-15B #836 Quiet Spike (Historical)	2006 - present	19
		F-15B #836 Research Testbed Aircraft	1993 - present	38
		F-15 #837 ACTIVE - Thrust Vectoring (Historical)	1993 - 1998	27
		F-15A - Flight Research (Historical)	1976 - 1981	12
		F-15A RPRV/SRV: Remotely Piloted Research Vehicle/Spin Research Vehicle (Historical)	1975 - 1977	2
		Highly Integrated Digital Electronic Control (HIDEC) (Historical)	1976 - 1993	7
F-16 AFTI (Historical)		AFTI - Advanced Fighter Technology Integration	1983	11
F-16XL (Historical)		Ship #1 (Historical)	1991 - 1996	39
		Ship #1 CAWAP - Cranked Aero Wing Aerodynamics Project (Historical)	1994 - 1996	13
		Ship #2 - Supersonic Laminar Flow (Historical)	1992 - 1996	30
F-18 Hornet
		Airborne Astronomy	1999 - present	4
		Mission Support Aircraft	1990 - present	28
		SRA - Systems Research Aircraft	1993 - 1998	22
		HARV - High Alpha Research Aircraft (Historical)	1987 - 1997	33
F-86 Sabre (Historical)		Chase Aircraft	1950s	37
F-100 Super Sabre (Historical)		Inertial Coupling (stability)	1954 - 1956	9
F-101 Voodoo (Historical)		Air Force fighter	1956	1
F-104 Starfighter (Historical)		Inertial coupling, reaction controls, noise research	1956 - 1973	28
F-105 Thunderchief (Historical)		Various flight research projects	1959 - 1968	1
F-106 Delta Dart (Historical)		Eclipse air tow	1997 - 1998	11
F-107A (Historical)		Evaluate sidestick flight control system	1957 - 1959	3
F-111 Aardvaark (Historical)		F-111A (Historical)	1968	2
		F-111 AFTI - Advanced Fighter Technology Integration (Historical)	1974 - 1986	6
		F-111E IPCS - Integrated Propulsion Control System (Historical)	1975	1
		F-111 TACT - Transonic Aircraft Technology (Historical)	1972 - 1984	3
Firebee Drone (Historical)		DAST - Drone for Aeroelastic Structures Testing	1977 - 1984	7
Gossamer Albatross (Historical)		Human Powered Aircraft	1980	5
Global Hawk		Unmanned aircraft	2007-present	7
Gulfstream III		General project support aircraft	2002 - present	5
Guppy		Pilot study and system transport	1962-present	10
HL-10 (Historical)		Lifting Body	1966 - 1970	29
Helios		Solar Powered Aircraft	1999 - present	36
HiMAT (Historical)		RPV - Highly Maneuverable Aircraft Technology	1979 - 1983	6
Hyper III (Historical)		RPV - Lifting Body reentry configuration	1969	4
Ikhana		Long-endurance, high-altitude unmanned research aircraft	Present	41
Inflatable Wing (Historical)		Inflatable Wing Technology Demonstrator	2001	9
Iron Cross Attitude Simulator (Historical)		Reaction Flight Control Systems	1956	3
KC-135A Stratotanker (Historical)		Evaluate capabilities of jet aircraft in air traffic control system and Winglet Study	1958 and 1979	5
KingAir		Support aircraft	1997 - present	7
L-1011		Adaptive Performance Optimization	1995 - present	5
		Wing Vortex Study (Historical)	1977	1
Lear 24 (Historical)		Jet transport	2001	1
LLRV (Historical)		Lunar Landing Research Vehicle	1964 - 1967	9
LRV (Historical)		Low Reynolds Vehicle	1981 - 1982	2
M2-F1 (Historical)		Lifting Body	1963 - 1964	22
M2-F2 (Historical)		Lifting Body	1966 - 1967	18
M2-F3 (Historical)		Lifting Body	1970 - 1972	10
MD-11 (Historical)		Propulsion Controlled Aircraft	1995	10
Mini-Sniffer (Historical)		Air sample gathering	1974 - 1977	4
Morphing Airplane		Inflight Configuration Changes	present	1
Oblique Wing Research Aircraft (Historical)		Oblique Wing Research	1976	2
Orion Crew Module		Orion crew module	2007 - present	16
OV-1C (Historical)		Stall speed warning system	1983	2
P-3D Orion (Historical)		Shuttle Tile Flight Tests Fixture	1987	2
P-38 Lightning (Historical)		World War II fighter	mid 1940s	1
P-51 Mustang (Historical)		Chase (X-1A), Pilot proficiency	1950s, 2000	4
PA-30 TwinComanche (Historical)		NASA 808 RPRV - Remotely Piloted Research Vehicle	1979 - 1980	2
Paresev (Historical)		Spacecraft landing control systems	1962 - 1964	10
Pathfinder (Historical)		Solar Powered Aircraft	1994 - 1997	35
Pathfinder-Plus		Solar Powered Aircraft	1998 - present	32
Pegasus (Historical)		Air-launched space booster	1989 - 1994	9
Perseus (Historical)		Environmental Research Aircraft and Sensor Technology	1993 - 1994, 1998	23
Phoenix Missile		Hypersonic testbed	2007 - present	3
PIK-20E (Historical)		Sailplane Research Aircraft - airflow over lifting surfaces	1981 - 1991	2
Power-Beaming		Continuous flight using beamed laser energy	2002-present	10
Propulsion Controlled Aircraft (PCA)		Propulsion Controlled Aircraft (PCA)	1993-present	9
Proteus		Environmental Research Aircraft and Sensor Technology	1999- present	7
Quiet Spike		Sonic boom research	2006 - present	19
R4D Skytrain (Historical)		Support aircraft	1950s	3
RF-84F (Historical)		Pitch up studies	1965	1
RSRA (Historical)		Rotor Systems Research Aircraft	1980 - 1981	2
Schweizer 1-36 (Historical)		Deep Stall Research	1983 - 1984	3
Shuttle Carrier Aircraft (SCA)		Space shuttle ferry flights	1981 - present	7
SOFIA		Stratospheric Observatory for Infrared Astronomy	2006 - present	68
Spacewedge (Historical)		Spacecraft Autoland Project	1991 - 1996	6
SRV (Historical)		RPV - Spin Research Vehicle	1973 - 1981	2
Shaped Sonic Boom Demonstration (SSBD)		Reducing sonic boom intensity	2003 - 2004	12
SR-71 Blackbird		High speed flight and sonic boom studies (Historical)	1990 - 1999	43
		Linear Aerospike SR Experiment (LASRE) (Historical)	1996 - 1999	21
		Ultraviolet Experiment	1994	1
T-33A (Historical)		Support and Flight Research	1958 - 1973	4
T-34C		Chase, pilot proficiency	1996 - present	10
T-37 (Historical)		Chase Aircraft, Wake Vortex Studies	1974	2
T-38		Chase, pilot proficiency	1970s - present	15
Theseus		RPV	1996 - present	16
Tier 3- Darkstar (Historical)		RPV	1995 - 1999	2
TU-144LL (Historical)		Supersonic Research	1996 - 1999	16
U-2 (Historical)		Never flown - CIA Cover Story	1960	1
Voyager (Historical)		Globe circling flight	1987	1
X-1 (Historical)		Supersonic flight	1946 - 1958	19
X-1A (Historical)		Supersonic flight	1946 - 1958	7
X-1B (Historical)		Supersonic flight	1946 - 1958	11
X-1E (Historical)		Supersonic flight	1946 - 1958	12
X-2 (Historical)		Supersonic swept wing	1955 - 1956	8
X-3 (Historical)		Sustained flight at Mach 2+, low aspect ratio wings,titanium construction	1953 - 1956	11
X-4 (Historical)		Semi-tailless aircraft	1954	9
X-5 (Historical)		Variable sweep wings	1952 - 1955	10
X-15 (Historical)		Hypersonic flight at high altitude	1959 - 1968	55
X-24 (Historical)		Lifting body flight research	1969 - 1975	30
X-29 (Historical)		Forward Swept Wing	1984 - 1992	18
X-31 (Historical)		Enhanced Fighter Maneuverability Demonstrator	1992 - 1995	27
X-33 (Historical)		Advanced Technology Demonstrator	1996 - 1999	25
X-34 (Historical)		Technology Testbed Demonstrator	1998 - 2000	30
X-36 (Historical)		Tailless Aircraft Research	1996 - 1997	27
X-37		Advanced Technology Demonstrator	1999 - present	5
X-38 (Historical)		Experimental Crew Return Vehicle	1995 - 2001	78
X-40A (Historical)		Space Maneuvering Vehicle	1996 - 2001	14
X-43A / Hyper-X		Unpiloted Hypersonic Research Vehicle	1996 - present	82
X-45A		X-45A Joint Unmanned Combat Air Systems (J-UCAS)	2001 - present	25
X-48B		Blended Wing Body	Present	18
X-Wing (Historical)		Rotor System Research Aircraft	1986 - 1988	3
XB-70A Valkyrie (Historical)		Stability and handling of large delta-wing aircraft at high speed	1967 - 1969	12
XF-91 Thunderceptor (Historical)		Prototype fighter	early 1950s	1
XF-92A (Historical)		Evaluate delta wing concept	1953	9
XV-15 Tilt Rotor Aircraft (Historical)		Improve design and efficiency of rotorcraft using tilt rotors	1980 - 1981	4
YF-12 Blackbird (Historical)		High speed, high altitude research, aerodynamic and thermal loads	1970 - 1978	10
YF-17 Cobra (Historical)		Prototype aircraft (future F-18)	mid 1970s	3
YF-23 (Historical)		Never flown at Dryden - US Air Force photo	1994	1
YF-102 Delta Dagger (Historical)		Delta wing research	1954 - 1958	4
YO-3A		In-Flight Acoustics Research	1997 - 2004	5
YRF-84F (Historical)		Pitch-up research	1954 - 1956	3
Aircraft Fleet Images
Fleet images		All Dryden aircraft fleet photos	1950 - present	50
Fleet Images from the 1950s (Historical)		Dryden aircraft fleet photos	1950 - 1959	11
Fleet Images from the 1960s (Historical)		Dryden aircraft fleet photos	1960 - 1969	14
Fleet Images from the 1970s (Historical)		Dryden aircraft fleet photos	1970 - 1979	2
Fleet Images from the 1980s (Historical)		Dryden aircraft fleet photos	1980 - 1989	4
Fleet Images from the 1990s (Historical)		Dryden aircraft fleet photos	1990 - 1999	15
Fleet Images from the 2000s		Dryden aircraft fleet photos	2000 - present	4
STS - Space Shuttle
ALT (Historical)		STS Approach and Landing Tests	late 1970s	6
Ferry Flights		STS - SCA Ferry Flights	1981 - present	9
Landings		STS Dryden/Edwards Landings	1981 - present	39
MDD		STS Mate-Demate Device	1978 - present	7
STS-1 Landing (Historical)		STS-1 Landing at Edwards	April 14, 1981	20
STS-76 Landing (Historical)		STS-76 Landing at Edwards	March 31, 1996	7
STS-92 Landing (Historical)		STS-92 Landing at Edwards	October 24, 2000	15
STS-98 Landing (Historical)		STS-98 Landing at Edwards	February 20, 2001	8
STS-100 Landing (Historical)		STS-100 Landing at Edwards	May 1, 2001	10
STS-111 Landing (Historical)		STS-111 Landing at Edwards	June 19, 2002	8
STS-114 Landing (Historical)		STS-114 Discovery Space Shuttle landing at Edwards Air Force Base	August 9, 2005	32
STS-117 Landing		STS-117 Atlantis Space Shuttle landing at Edwards Air Force Base	June 22, 2007	12
STS-Miscellaneous		STS-Miscellaneous	2005	9
Dryden Center Research Facilities Images
Dryden Research Facilities		Dryden laboratories and buildings	1946 - present	30
Flight Simulators		Dryden flight simulators	1958 - present	17
Flight Loads Laboratory		Stress testing of aircraft under conditions expected in flight	1970 - present	16
Flow Visualization Facility		Water Tunnel Flow Studies	1983 - present	3
Other Dryden Images
Aerodynamic Truck Research (Historical)		Air Flow Research	1975 - 1981	2
Directors		Dryden Center Directors portraits	1946 - present	19
Miscellaneous		Miscellaneous Dryden photos	N/A	14
People		Dryden people	1946 - present	56
Pilots		Dryden Research Pilots and their aircraft	1946 - present	79
Schlieren Photography		Shock Wave Visualization Research	1993 - present	1
Visitors		Guest speakers, visiting dignitaries, etc	2002 - present	22