Milky Way's center will be revealed by NASA's Webb Telescope

The center of our galaxy is a crowded place: A black hole weighing 4 million times as much as our sun is surrounded by millions of stars whipping around it at breakneck speeds. This extreme environment is bathed in intense ...

Spitzer spots a starry region bursting with bubbles

This infrared image from NASA's Spitzer Space Telescope shows a cloud of gas and dust full of bubbles, which are inflated by wind and radiation from young, massive stars. Each bubble is filled with hundreds to thousands of ...

Landsat 9 instrument ready for spacecraft assembly

The Landsat 9 instrument that will help scientists detect deforestation, monitor crops and track potentially toxic algal blooms, among many other uses, is now built, tested, and in place to be assembled onto the spacecraft.

Found: three black holes on collision course

Astronomers have spotted three giant black holes within a titanic collision of three galaxies. Several observatories, including the Chandra X-ray Observatory and other NASA space telescopes, captured the unusual system.

NASA sees Karen regain tropical storm status

NASA-NOAA's Suomi NPP satellite passed over the Caribbean Sea and used infrared light to obtain temperature information about Karen's cloud tops. Data showed powerful thunderstorms re-developed in around the storm's center ...

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Infrared (IR) radiation is electromagnetic radiation whose wavelength is longer than that of visible light (400-700 nm), but shorter than that of terahertz radiation (100 µm - 1 mm) and microwaves (~30,000 µm). Infrared radiation spans roughly three orders of magnitude (750 nm and 100 µm).

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux, which includes infrared (47% share of the spectrum), visible (46%), and ultra-violet (only 6%) light. Bright sunlight provides luminance of approximately 100,000 candela per square meter at the Earth's surface.

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