The photo above is the mysterious zodiacal light shining behind the Faulkes Telescope North on Maui. Rob Ratkowksi captured it from the University of Hawaii High Altitude Observatory.
At early evening tonight – and for the next several weeks – those in the Northern Hemisphere can look for this mysterious zodiacal light. The next two weeks provide a good window for watching the zodiacal light in the west each night as full darkness falls, because the moon is rising later at night now.
From the Northern Hemisphere, late February through April – the weeks around the March equinox – present the best time of the year to catch this pyramid of light illuminating the western sky as soon as true darkness falls. Look westward about 80 to 120 minutes after sunset.
This observation is not for city dwellers, but if you find yourself beneath a dark country sky – or perhaps driving along a country road after dusk – look for this eerie light.
On the other hand, from the Southern Hemisphere, this time of year presents the zodiacal light in the morning sky, in the east just before dawn. A bright moon is up before dawn in the last week of March 2016. If you’re in the Southern Hemisphere, you may need to wait until the end of the first week of April – when the moon has waned to a thin crescent or left the morning sky entirely – to look for the zodiacal light before dawn.
In 2016, evening watchers can look for the zodiacal light to jut upward from the western horizon and toward the constellation Taurus. Taurus can be identified by its two most prominent signposts, the star Aldebaran and the Pleiades star cluster. Look for them to adorn the western sky as dusk gives way to nightfall.
The zodiacal light is caused by sunlight reflecting off interplanetary dust particles that orbit the sun within the inner solar system. People at mid-northern latitudes can see the zodiacal light after dusk at present because the ecliptic – the approximate plane of the solar system – is nearly perpendicular to the horizon on March/April evenings.
The farther south you live within the Northern Hemisphere’s temperate zone, the more likely you are to spot the zodiacal light.
Bottom line: In the early evening, look for a pyramid-shaped light in the west when true darkness falls. This is the zodiacal light. You need a dark sky to see it.