Indonesian Solar Eclipse
The forests of Indonesia are homes to one of the richest populations of songbirds in the world. Ecotourists travel from far and wide to listen to them sing from the leafy canopy of the nation’s volcanic islands.
On March 9th, 2016, not long after sunrise, a time when the forest is usually filled with tweets, trills, and warbles, the songbirds of Indonesia will go silent.
That is how songbirds respond to a total eclipse of the Sun.
Eclipse chasers have had the date marked on their calendar for years. It is the only total eclipse of 2016. During the early hours of March 9th, the new moon will pass directly in front of the sun. The moon’s shadow will lance down toward Earth, making landfall initially in the Indian Ocean, racing across South East Asia, and from there onto the Pacific Ocean where the eclipse will be partially visible in parts of Alaska, Guam, Hawai’i, and American Samoa.
Inside the moon’s cool shadow, sky watchers can look up and see the sun’s ghostly corona, a mesmerizing sight.
Sarah Jaeggli, Solar Scientist at NASA’s Goddard Space Flight Center says “I cannot stress enough how special solar eclipses are. Eclipses let us see a region of the sun’s atmosphere called the ‘corona’ that is generally invisible to us. We can see the sun’s corona from satellites and ground-based observatories using devices called ‘coronagraphs,’ but we simply cannot build a coronagraph that is as good as the moon passing in front of the sun. The large size of the moon and its distance from us means less stray light from the sun can scatter around the edges and interfere with observations of the sun’s faint atmosphere.”
She emphasizes that “the brief glimpses of the corona during total solar eclipses are not to be wasted.”
The experience of a total eclipse is, however, more than just the sight of the corona. It is also the feel of the moon’s cool shadow that lowers air temperatures by as much as 5 degree Finside the path of totality. And it is the sound of wildlife responding to the odd and unexpected nightfall.
Songbirds go quiet.
Frogs and crickets replace the birdsong with their own nighttime chorus.
Charlotte Vermeulen, a biologist at the Artis Zoo in Amsterdam, Netherlands says, "Dragonflies hide under a leaf, ants return to their nest, sheep walk back to their sleeping place, cattle egrets return to their nocturnal roost, diurnal grasshoppers chirp more slowly and then stop." In August 1999, there was a 98 percent partial solar eclipse in Amsterdam. She recalls many people coming to the zoo during the eclipse just to see the reactions of the animals.
On March 9th in Indonesia, totality will last for about 2 minutes, giving humans and wildlife alike plenty of time to react.
NASA scientists will be in Indonesia using the eclipse to test a new telescope configuration designed to study the solar corona. The new instrument will be able to observe the temperature and velocity of material in the solar corona, providing information that could help scientists understand the physics of the corona, including how the sun's atmosphere gets so much hotter than its surface. They hope to fly this design in space in the future, but an eclipse on Earth gives them a great opportunity to do some inexpensive testing.
This is the last total solar eclipse before the “Big One” next year. On August 21st, 2017, the sun and moon will line up again. This time the moon’s shadow will cross the continental United States, creating a total eclipse in easy driving distance of tens of millions of people. It will likely be the best observed eclipse in human history.
If you plan to be one of those eclipse chasers, just remember, there’s more than one way to experience an eclipse. See the corona. Feel the cool air. Listen to the songbirds and other wildlife.
The preview begins in Indonesia on March 9th.
For more news about solar eclipses, stay tuned to science.nasa.gov.