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April features two striking astronomy events, both of a reddish hue.
The Hawaiian islands are perfectly situated to see all of the total lunar eclipse on April 14, a celestial event that runs from roughly 8 to 11:30 p.m. In addition, Mars reaches its brightest point in the past eight years.
The eclipse will most likely be the most stunning astronomical event we’ll see all year.
It technically starts at 6:53 p.m., shortly after the full moon rises at 6:42 p.m. However, for this first hour, you will see no change in the full moon’s appearance.
This first phase of the lunar eclipse is called the "penumbral phrase," as the moon starts to move into the fainter outer shadow, or penumbra, of the Earth.
At 7:58 p.m., the partial phase of the lunar eclipse will begin. The moon begins to cross into the deep inner shadow of the Earth, which is called the umbra.
For the next hour or so, you will see a deeper and deeper "bite" taken out of the moon as more of the moon slides into the Earth’s deep inner shadow.
Meanwhile, the part of the moon that is not yet in the umbra will remain as bright as a regular full moon.
At 9:06 p.m., the total phase of the eclipse begins. This phase lasts more than 70 minutes, running until 10:24 p.m. At this point, the entire moon will be in the Earth’s dark inner shadow.
During this phrase, the Earth is exactly between the sun and the moon, and Earth blocks most of the sun’s light from hitting the moon.
However, while the Earth’s atmosphere does block the shorter wavelengths of blue light from getting past the earth and hitting the moon, the longer wavelengths of red light make it through Earth’s atmosphere and continue on to strike the moon. That is why the moon often turns red during a total eclipse.
The total phase of this lunar eclipse ends as the moon starts to move out of the Earth’s dark shadow.
There will be another partial phase after this total phase ends. More of the moon will be unveiled from 10:24 to 11:33 p.m., reversing the "bitten cookie" effect that happened before the total phase. By 11:33 p.m., the visible part of the eclipse will be over and the moon will look exactly like a normal full moon again.
The Bishop Museum will have an eclipse-viewing event from 8 to 11:30 p.m. The Hawaiian Astronomical Society, always great at providing support for these special events, will be staffing telescopes on the Great Lawn.
The cost is $8 adults, $6 for ages 4-12, and free for members and kids under 4.
In addition to the telescopes on the lawn, we’ll offer a 25-minute show on lunar eclipses (every half-hour from 8:30 to 11 p.m. inclusive) in the Watumull Planetarium.
Reservations are required for this event. Go to the museum home page at www.bishopmuseum.org or call 848-4168.
MARS HITS ITS PEAK
No planet varies in its brightness like Mars does. For much of last year Mars has seemed a faint red spark, but this April it shines brighter than any time since December 2007.
Mars is in opposition on April 7-8, meaning there is a straight line between the sun, Earth and Mars; when a planet is in opposition it tends to shine most brightly.
Mars will rise in the east at dusk, be high overhead at midnight and set at dawn in the west. At the start of April, look for Mars rising in the east at 7:45 p.m., just as full darkness settles in. Mars hits its highest point, about two-thirds of the way up in the south, at 1 a.m., and sets around daybreak.
Mars’s peak brightness occurs April 7-10, when it will be as bright as Sirius, the brightest star. On these nights, look for Mars about 12 degrees above the east as it gets dark (one fist at arm’s length). It will reach its highest point in the south just after midnight and set in the west at dawn.
By the end of April, Mars will be nearly halfway up in the east at dusk reaches its highest point in the south just before 11 p.m., and it sets at 4:45 a.m.
OTHER APRIL PLANETS
Look for a very bright Jupiter (minus-2 magnitude) at dusk in early April almost exactly overhead at dusk. It’ll work its way down the western sky throughout the evening and set in the west just after 1 a.m.
By the end of April, Jupiter will be halfway up in the west at dusk and sets a little before midnight. Jupiter shines more brightly than any other dot in the evening sky — even Mars at its peak brightness.
Venus is spectacular in the predawn sky, shining at minus 4.1. The planet does not change much in appearance all month; it rises in the east-southeast around 4 a.m., and will be about one-third of the way up in the east at daybreak.
In early April, Saturn rises in the east by 9:45 p.m., crosses the meridian at 3:15 a.m. and is about halfway down in the west at daybreak. By the end of April the ringed planet rises in the east around dusk, is overhead at 1 a.m. and is low in the west as day breaks. Saturn appears in front of the claws of Scorpius the Scorpion.
LYRID METEOR SHOWER
The Lyrid shower peaks on the night of April 21-22. Stay up late on April 21, past midnight, and look for shooting stars. The shower is active from April 16 to 25.
On the prime viewing night, April 22, the third-quarter moon rises in the east at about 1:20 a.m. in the same direction as where the meteors come from, so this will provide some interference.
Mike Shanahan is director of Education, Exhibits and Planetarium. For more information, go to www.bishopmuseum.org/planetarium/planetarium.html
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