NASA's SDO catches the moon crossing the sun in a partial lunar eclipse!

Image courtesy: NASA’s Goddard Space Flight Center/SDO/Joy Ng, producer

New Delhi: The sun is another world unto itself. Mighty, mystifying and strong, the biggest star in the solar system is as important for the sustenance of life as its wrath is devastating.

NASA's team of scientists have been working tirelessly toward understanding the enigma that is the sun.

Time and again, the US space agency has released videos and images of the lumionous body spewing solar material and oozing plasma on its surface, which makes one wonder what other secrets the gigantic ball of fire may be holding.

On May 25, NASA's team at the Solar Dynamic Observatory (SDO) that has been studying the sun since it was launched on February 11, 2010, witnessed a partial solar eclipse in space when it caught the moon passing in front of the solar body.

According to NASA, the lunar transit lasted almost an hour, between 2:24 and 3:17 p.m. EDT, with the moon covering about 89 percent of the sun at the peak of its journey across the sun’s face. The moon’s crisp horizon can be seen from this view because the moon has no atmosphere to distort the sunlight.

While the moon’s edge appears smooth in these images, it’s actually quite uneven. The surface of the moon is rugged, sprinkled with craters, valleys and mountains.

Another lunar transit will occur later this summer on August 21, wherein the moon will only barely hide part of the sun.

However, on the same day, a total eclipse will be observable from the ground. A total solar eclipse — in which the moon completely obscures the sun — will cross the United States on a 70-mile-wide ribbon of land stretching from Oregon to South Carolina. Throughout the rest of North America — and even in parts of South America, Africa, Europe and Asia — a partial eclipse will be visible.

As per the US space agency, the moon’s rough, craggy terrain influences what we see on Earth during a total solar eclipse. Light rays stream through lunar valleys along the moon’s horizon and form Baily’s beads, bright points of light that signal the beginning and end of totality.

The moon’s surface also shapes the shadow, called the umbra, that races across the path of totality: Sunlight peeks through valleys and around mountains, adding edges to the umbra. These edges warp even more as they pass over Earth’s own mountain ranges. Visualizers used data from NASA’s Lunar Reconnaissance Orbiter, or LRO, coupled with NASA topographical data of Earth, to precisely map the upcoming eclipse in unprecedented detail. This work shows the umbral shape varies with time, and is not simply an ellipse, but an irregular polygon with slightly curved edges.