In test images of distant galaxies, an array of Event Horizon Telescopes has achieved the highest resolution observations ever taken from Earth. Taken using just a few of the telescopes that make up ...

Almost since the beginning of man's time on Earth, people have been recording observations of nature. They drew on cave walls and painted stories on teepees and sheepskin. And we are still doing it.

For the past 100 years, park rangers at Denali National Park have done two things every day: feed the sled dogs and record weather observations. This valuable record of temperature, precipitation, ...

A naturalist in Madagascar; a record of observation, experiences, and impressions made during a period of over fifty years' intimate association with the natives and study of the animal & vegetable ...