Your shadow
always tails you,
except today

When the sun passes
directly over Hawaii, presto,
shadows vanish

By Helen Altonn
Star-Bulletin

If you were in Honolulu and looked for your shadow today when the sun was directly overhead, it wasn't there. It won't be there tomorrow, either.

The sun is at its most northerly position in the sky at summer solstice June 21 when it passes directly over the Tropic of Cancer at midday, says University of Hawaii astronomer Richard Wainscoat.

It passes directly over Hawaii twice each year -- in May and July -- because the islands are located a few degrees south of the Tropic of Cancer, he said.

The danger of sunburn is highest during this period, he cautioned.

For Honolulu residents, shadows will disappear at 12:28 p.m. tomorrow, as they did at that time today.

"You can see this most dramatically by looking at the shadow of a tall slender object, such as a lamp post," Wainscoat said.

When the sun passes directly overhead depends on your location, he said. ""The further west you are, the later it happens." It occurred May 18 on the Big Island and Sunday on Maui.

Wainscoat computed these as the best times to note the absence of shadows:

Honolulu: Today and tomorrow -- 12:28 p.m.; July 15, 16 -- 12:37 p.m.

Kahuku: Friday -- 12:29 p.m.; July 13, 14 -- 12:37 p.m.

Kahului, Maui: July 18 -- 12:32 p.m.

Lihue, Kauai: Sunday -- 12:35 p.m.; July 11, 12 -- 12:42 p.m.

Hilo: July 24 -- 12:26 p.m.

Shadows will be very small within a few days of those dates as the sun passes nearly overhead, Wainscoat said.

He noted that the times when the sun passes overhead in July are about 10 minutes later than in May. This is because the Earth's orbit around the sun is slightly elliptical rather than circular.