Story and Photos by Gabie Cardenas
On June 5th, 2012, we witnessed another astronomy event. An annular solar eclipse, this one produced by Venus transiting/passing in front of the Sun.
Groups of amateurs astronomers, such as COC Astronomy Club, the Local Group Local Astronomy Club of Santa Clarita were planted at the place with the best western view in Santa Clarita, Centre Pointe shopping center (near the Canyon Country Walmart and Dick’s Sporting Goods). Viewing devices included anything from fancy expensive auto-tracking telescopes and home-made powerful viewing devices, to projections on pieces of cardboard through a binocular’s lens.
This is the last transit of the planet Venus across the face of the sun for the next 100 years! A transit of Venus occurs when Venus passes directly between the sun and earth. This alignment is rare, coming in pairs that are eight years apart but separated by over a century. The last transit of Venus was a thrilling sight in 2004. After June 2012, the next event occurs in 2117.
Transits of Venus have a strange pattern of frequency. A transit will not have happened for about 121 ½ years (prior to 2004, the last one was 1882). Then there will be one transit (such as the one in 2004) followed by another transit of Venus eight years later (in the year 2012). Then there will be a span of about 105 ½ years before the next pair of transits occur, again separated by eight years. Then the pattern repeats (121 ½ , 8, 105 ½ , 8).
Transit of Venus pairs since the invention of the telescope:
1631 (not witnessed) & 1639
1761 & 1769
1874 & 1882
2004 & 2012
If Venus and the earth orbited the sun in the same plane as the sun, transits would happen frequently. However, the orbit of Venus is inclined to the orbit of earth, so when Venus passes between the sun and the earth every 1.6 years, Venus usually is a little bit above or a little bit below the sun, invisible in the sun’s glare.
A similar thing happens with our moon. Every month the moon passes between the sun and the earth, yet we do not see a solar eclipse every month.
The transit of Venus is essentially an annular eclipse of the sun by Venus.
As with any solar observations, use specialized eclipse glasses, strong welding plates or, just as some amateur astronomers were showing the passers by, use a projection.