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Light the Bat-Signal! Just kidding, it's time for another #ThrowbackThursday! Before rockets made direct high-altitude measurements possible after WWII, scientists at DTM probed the upper atmosphere with powerful beams of light. In the late 1930s, a team of researchers headed by staff member Ellis Johnson turned flickering carbon arc searchlights skyward from the Broad Branch Road campus. By observing how atmospheric gases scattered the light, Johnson was able to determine the ozone content of the lower atmosphere, as well as the temperature and pressure of the air up to 40 km high – well above the range of sounding balloons. Plans were laid for building even stronger light sources and more sensitive photoelectric receivers that could reach unprecedented heights of 70-90 km, but world events intervened. By 1941, with America’s entry into World War II appearing inevitable, Johnson and his group were reassigned to national defense projects and the searchlights were shut down. Photo taken on the Broad Branch Road campus in December 1939. #CarnegieScience #CarnegieHistory #HistoryofScience #ScienceHistory #TBT #ScienceDaily #ScienceofLight #PlanetaryScience #atmosphere #atmosphericscience #lightpainting #vintagephotos #steampunk #electricity #coolscience #blackandwhite
The Library and Archives are located in the Abelson Building of the Carnegie Institution's Broad Branch Road campus in Washington, DC.
Books and periodicals in the earth and planetary sciences, physics, chemistry, biology, mathematics, and statistics are housed in the Main Library on the 2nd and 3rd floors of the Abelson Building. Current journals and special collections are shelved in the Reading Room. Reference works (encyclopedias, handbooks, atlases, etc.), laboratory safety information, and writing guides are located in A-208. A separate Astronomy Library in Research Building Room 272 holds materials in stellar/galactic astronomy and exoplanet research.
The Abelson Collaboration Center (ACC), located in A-208, has advanced audiovisual equipment and may be reserved for group meetings, presentations, classroom instruction, and videoconferencing
All borrowed library materials must be signed out. Only persons with formal Carnegie Institution affiliation (staff members, post-docs, pre-docs, interns, visiting investigators) are entitled to borrow materials. The honor system is used; please complete a sign-out card for each item you borrow and deposit in one of the boxes provided. When returning materials, place them on the cart next to the copier on the 2nd floor -- please do not reshelve them yourself.
Books and maps may be borrowed for extended periods, but are subject to recall at any time. Books marked "Reference Use" may not be taken out of the library, except by special arrangement. Current issues of journals do not circulate. They may be removed from the Reading Room briefly for photocopying, but then must be returned immediately. Borrowing of back volumes (bound or unbound) from the periodicals stacks is strongly discouraged; if necessary, however, these older journals may be signed out for a period of one week.