Venus buzzes Regulus
BY MARK ARMSTRONG
Posted: 2 September 2014

2
Venus has a close encounter with first magnitude star
Regulus, constellation Leo's luminary, in the dawn TWILIGHT on the mornings of
5 and 6 September.
Look for Venus in the dawn TWILIGHT during September.
A keen eye, or more likely, binoculars will show Regulus but be careful not to
observe it through binoculars if the Sun is about to rise. AN graphic by Greg
Smye-Rumsby.
Keen observers and early risers with an uninterrupted
eastern horizon will be familiar with Venus' presence as a dazzling morning
star in the morning sky for nearly all of 2014. But the second planet from the
Sun's apparition is coming to an end as it heads back towards the Sun, so
during September it will hang under ten degrees above the horizon around 30-40
minutes before sunrise. Despite the low altitude, given a clear and transparent
sky binoculars should easily show the pair, with Venus' magnitude -3.9 totally
overpowering Regulus' +1.3.
On 5 and 6 September Venus rises at 5am and its
elongation from the Sun has shrunk to 13 degrees from 47 degrees at its
greatest elongation of 47 degrees west back in March. By 5.45am the pair will
have risen to about six degrees and will be under a degree APART with Venus
above Regulus. It's roughly the same scenario next morning, but Venus will be
side by side with Regulus.
A small telescope will show Venus at near full-phase
(97 percent) with an apparent diameter of 10 arcseconds. Venus will grimly
hang-on in the morning sky but by the start of the third week of September it's
essentially lost to the TWILIGHT. However, experienced observers with perhaps
at least 100-150-mm telescope can observe Venus in daylight during September,
the addition of a red filter (W25 or W29) helping to increase the contrast
between Venus and the sky.
Extreme caution must be exercised to ensure the nearby
Sun does not enter the field of view, which is why this observation is not
recommended for inexperienced observers or absolute beginners.
No comments:
Post a Comment