But the automatic imagers and processing of NASA’s MODIS Rapid Response System continue to work without interruption.
The image to the right was taken at 2:15 p.m. Eastern Daylight Time on October 9, 2013, when NASA’s Aqua satellite passed over eastern parts of Canada and the northeastern United States.
There are only a handftul of days at best each autumn when clear skies there allow the rich tapestry of fall foliage to be seen from space.
And the lengthening shadows of fall combined with a few frosty nights had led to fall's spectacular landscape being there on one of those days.
Hues of burnt-orange and amber can be seen in many areas of northern New York and New England, north of where high clouds muted them in the lower portion of the image. They stand out in contrast to some of the conifer forests and large lakes that can also be seen.
Autumn’s rich colors are the result of chemical processes that take place in the tree as the season changes. During spring and summer, the leaves served as factories where most of the foods necessary for the trees' growth are manufactured.
This food-making process takes place in numerous cells containing the pigment chlorophyll, which gives the leaf its green color. Along with the green pigment, leaves contain yellow or orange carotenoids, which also give the carrot its familiar color. Most of the year, these yellowish colors are masked by the greater amount of green coloring provided by the chlorophyll.
But in the fall, partly because of changes in the period of daylight and changes in temperature, the leaves stop their food-making process. That causes the chlorophyll to break down, then the green color disappears and the yellowish colors that remain become visible and give the leaves part of their fall splendor.
Other chemical changes occur, leading to the formation of additional pigments in the leaves that range from yellow to red to blue.
Full story and image: NASA