Private: Elusive Mercury shines in July 2008 dawn sky
June 30, 2008 - ES Tonight
(Image credit: NASA)
Mercury, the closest planet to the sun, is the bright planet seen least often.
And that’s not because this world appears faint in our sky. Mercury often shines as brilliantly as a bright star. But Mercury is elusive because when it’s visible, it’s nearly always in twilight, either at morning dawn or evening dusk.
Presently, Mercury shines before dawn. As seen from Earth today, it’s reaching its greatest elongation west of the sun. What this means is that Mercury appears in the east before dawn.
The solar system’s innermost planet is always bound to the sun by a short tether. Given clear skies, Mercury might be visible for 30 to 45 minutes before twilight begins.
Throughout July, no matter where you are on Earth, Mercury will sit over your east-northeastern horizon before “sunrise”:http://earthsky.org/article/sunrisesunset-moonrisemoonset-almanacs. With an unobstructed view eastward, chances are you’ll spot Mercury about an hour before the sun comes up – within two hours of sunup at far southern latitudes – like in New Zealand.
At early dawn for the next couple of weeks, look for Mercury to hover over the sunrise point on your horizon. Even though this modestly bright world can be seen with the eye alone, binoculars will help you to reel Mercury in from the July predawn twilight.