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The thrill of discovery awaits you in the Smithsonian Learning Lab. From the Discovery space shuttle to the Star Spangled Banner to dinosaur fossils, the Learning Lab gives everyone with a desire to learn the opportunity to explore the Smithsonian's rich resources anytime, anywhere. Start discovering what interests you today, and find your inspiration from more than a million multimedia resources.

Suggested Discoveries

Albert Einstein

National Portrait Gallery
Albert Einstein transformed the world of physics with his groundbreaking theory of relativity, and in 1921 he received the Nobel Prize for “his services to theoretical physics” and “his discovery of the law of photoelectric effect.” The German-born physicist was visiting the United States when Hitler and the Nazis came to power in his homeland in 1933. Einstein never returned to Germany. Instead, he accepted a position at the Institute for Advanced Study in Princeton, New Jersey—the newly established academic institution that would become a major center for research in theoretical physics. In residence at the institute for the remainder of his life, Einstein continued to publish, work on the interpretation of quantum theory, and wrestle without success on his unified field theory. He became a U.S. citizen in 1940.

Karsh relished the opportunity to photograph Einstein, whose face, “in all its rough grandeur, invited and challenged the camera.”

Star-Spangled Banner

Smithsonian Archives - History Div
The Star-Spangled Banner, undated. Note that the "A" sewn into the flag has been whited out in the image The Star-Spangled Banner was the Garrison flag of Ft. McHenry, Baltimore, during the bombardment of the fort by the British, September 13-14, 1814, when it was successfully defended by Colonel George Armistead. The flag was presented to the United States National Museum, Washington, D.C., by Mr. Eben Appleton of New York, the grandson of Colonel George Armistead.

North American X-15

National Air and Space Museum
North American X-15, rocket powered experimental aircraft; black titanium skin with wedge shaped horizontal stablizer; yellow stripe NASA inisignia on tail with stars and red bars United States national insignia on wings; white letter text "U.S. AIR FORCE" on the sides of the fuselage.

The North American X-15 rocket-powered research aircraft bridged the gap between manned flight within the atmosphere and manned flight beyond the atmosphere into space. After completing its initial test flights in 1959, the X-15 became the first winged aircraft to attain velocities of Mach 4, 5, and 6 (four, five, and six times the speed of sound). Because of its high-speed capability, the X-15 had to be designed to withstand aerodynamic temperatures on the order of 1,200 degrees F.; as a result, the aircraft was fabricated using a special high-strength nickel alloy named Inconel X.

Air-launched from a modified Boeing B-52 Stratofortress aircraft, the X-15 required conventional aerodynamic control surfaces to operate within the atmosphere and special "thruster" reaction control rockets located in the nose and wings of the aircraft to enable the pilot to maintain control when flying on the fringes of space. Indeed, the X-15 design was so much like that of a space vehicle that during the formative days of Project Mercury, America’s first attempt to put a man in orbit, North American and National Air and Space Administration (NASA) engineers gave serious consideration to utilizing a growth version of the X-15 for the manned orbiting mission. This plan was dropped in favor of using a blunt-body reentry vehicle. Because of the potential dangers to the pilot should the X-15’s pressurized cockpit lose its atmosphere while the aircraft operated in a near-space environment, X-15 pilots wore specially developed full-pressure protection ‘spacesuits’ while flying the experimental plane.

Three X-15 research aircraft were built and flown, completing a total of 199 research flights. The National Air and Space Museum has the historic X-15 #1, Air Force serial 56-6670. The X15 #2 (56-6671) was rebuilt following a landing accident as the advanced X-15A-2, having increased propellant capacity and, hence, a higher potential performance. The X-15A-2 was the fastest X-15 flown, and it is now on exhibit at the Air Force Museum, Wright-Patterson Air Force Base, Ohio. The X-15 #3 (56-6672) featured an advanced cockpit display panel and a special adaptive control system. The aircraft made many noteworthy flights until it crashed during atmospheric reentry, following pilot disorientation and a control-system failure. The pilot, Capt. Michael Adams, was killed.

The X-15 flew faster and higher than any other airplane. A peak altitude of 354,200 feet (67± miles) was reached by the X-15, and the X-15A-2 attained a speed of Mach 6.72 (4,534 mph) while testing a new ablative thermal protection material and a proposed design for a hypersonic ramjet. Various proposals were set forth for modifying the aircraft to accomplish new and even more radical tasks. At one point, NASA scientists planned to test a hydrogen-fueled supersonic combustion ramjet engine mounted on the X-15s lower vertical fin. A mock-up of this proposed installation was flight-tested on the X-15A-2. Other ideas included modifying the X-15 with a slender delta wing and using the aircraft as a booster for small satellite launch vehicles. None of these ideas, however, came to fruition.

The X-15 spearheaded research in a variety of areas: hypersonic aerodynamics, winged reentry from space. life-support systems for spacecraft, aerodynamic heating and heat transfer research, and earth sciences experiments. A total of 700 technical documents were produced, equivalent to the output of a typical 4,000-man federal research center for more than two years.

Development of the X-15 began in 1954, in a joint research program sponsored by the National Advisory Committee for Aeronautics (forerunner of NASA), the U.S. Air Force. the U.S. Navy, and private industry. North American was selected as prime contractor on the project following a competition in which Douglas. Republic. and Bell also participated. By the time of its first airborne test, flight research was too complex to rely on simple air-to-ground communications near a test field. The Air Force and the National Advisory Committee for Aeronautics developed a special 485-mile-long test corridor stretching from Wendover Air Force Base. Utah. to Edwards Air Force Base. California. It was planned that the X15 would be air-launched from a Boeing B-52 near Wendover. then fly down this corridor, the High Range. to Edwards. monitored by tracking stations at Ely and Beatty. Nevada. and at Edwards. The range lay along a series of flat dry lakes. where the X-15 could make an emergency landing. if necessary. Nothing this extensive had previously existed in flight research, and it foreshadowed the worldwide tracking network developed by American manned spacecraft ventures. The X-15 would complete its research mission and then. followed by special Lockheed F-104 chase aircraft. would land on the hard clay of Rogers (formerly Muroc) Dry Lake. Because the X-15 featured a cruciform tail surface arrangement. it was necessary for the designers to make the lower half of the ventral fin jettisonable prior to landing so that the conventional two-wheel, nose-landing gear and two tail-mounted landing skids could support the aircraft.

Pressure Suit, RX-2-A, Constant Volume, Litton

National Air and Space Museum
This RX-2-A Advanced Extra-Vehicular Suit is an experimental constant volume suit was manufactured by Litton Industries who made a series of "hard" suits during the early 1960s. These experimental suits were designed to maintain an almost perfectly constant volume while enabling a full range of body motions. They could operate at higher pressure, thus reducing the time-consuming oxygen pre-breathing period before extra vehicular activities.

It has more sophisticated shoulder joints than the RX-2, and closes with a dual-plane closure at the back. It operated at 5psi instead of the 3.7psi of the Apollo soft suits.

Transferred to the National Air and Space Museum from NASA in 1977

Dizzy Gillespie [ca. 1984-1990 : black-and-white photoprint]

Archives Center - NMAH
Gillespie playing trumpet.

Postcard of Horned Dinosaur Skeletons

Smithsonian Archives - History Div
The National Museum of Natural History (NMNH) first opened to the public on March 17, 1910, as the new United States National Museum. The National Museum was first housed in what is now the Arts and Industries Building.

Grayscale postcard of two skeletons of horned dinosaurs on exhibit at the United States National Museum, now the National Museum of Natural History. The larger one is a Triceratops skeleton, and the smaller one is a Brachyceratops skeleton. The postcard is unused, but the message side has a printed note about the dinosaurs: "These skeletons of two extinct reptiles known as Horned Dinosaurs were discovered in the Cretaceous rocks of the West. Triceratops, the larger of the two specimens, shown, named for the three horns on its head, was about 20 feet long. With a head 6 feet in length it had the largest skull of any known reptile. The other skeleton, Brachyceratops, less in size than the skull of the Triceratops, is the smallest of North American horned dinosaurs. Both of these animals were plant eaters, living in the swamps of the western plains. They became extinct over 100,000,000 years ago."

Poster

Cooper Hewitt, Smithsonian Design Museum

Stuart Perry Gas Engine Patent Model

National Museum of American History, Kenneth E. Behring Center
This model was submitted to the U.S. Patent Office with application for Patent no. 4800, issued October 7, 1846.

This engine is very similar to the Perry engine of 1844 (US National Museum accession number 309253). It differs in that the cylinder is water-jacketed and the hot cooling water is used to heat the fuel retort. Ignition is effected by heated platinum exposed to or separated from the explosive mixture by a valve.

The model shows a horizontal double-acting engine completely water-jacketed. Beside the cylinder is the retort for generating the vapors. Air is mixed with the vapor in a valve box above the retort, and valves operated by cams from a lay shaft admit the explosive mixture to passages leading to the cylinder. The gas is ignited by incandescent platinum, and combustion continues during about one-third of the stroke, the expansion of the products of combustion forcing the piston to the end of the stroke.

To start the engine it was necessary to heat the water about the retort to generate the vapor and to heat the igniter. When running, the engine developed sufficient heat for both purposes.

Perry designed this engine so that the water served not only to cool the cylinder but also to lubricate the piston and piston rod.

Reference:

This description comes from the 1939 Catalog of the Mechanical Collections of the Division of Engineering United States Museum Bulletin 173 by Frank A. Taylor.