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Rare planet Mercury transit set for early morning of Nov. 11

(NASA-JPL Photo)

Mercury, the smallest of the major planets and one of the most difficult planets to observe, will perform a rather rare transit across the disk of the sun Monday!

Mercury is located on average some 36 million miles from the sun and orbits the sun in a mere 88 days.

The rare event with Mercury is that it can transit across the disk of the sun, 13 to 14 times in a century.

This rare event will occur for Arizona observers during the morning of Nov. 11.

Extreme caution needs to be followed, as you must have a small telescope with the proper eye protection to view the event.

This column will provide many safe ways to view the event, assuming that we have clear skies and a good view of the southeastern sky.

Mercury will begin its long march on the solar disk at 5:37 a.m. Arizona time, long before the sun rises here. But get ready as the sun will rise here at 6:55 a.m.

At that time, lucky observers with a small protected telescope will get to view the inky black image of the tiny planet Mercury on the disk of the sun.

The entire transit of Mercury will take some 5 hours and 25 minutes for the planet to move across the sun.

Mercury will be at its most central position on the sun, at 8:20 a.m. Arizona time.

At that time, Mercury will be nearly dead center on the sun and will not be this close again until the transit of Nov. 12, 2190.

The best way to observe the event will actually be on the internet – here is a link to a live stream of the event.

Here is an image of how Mercury looks crossing the sun.

Here is a graphic of the Mercury transit of Nov. 11, 2019.

It is very important to have the proper solar filters on any telescope or camera that you are using to view this event.

The best Dr. Sky suggestion is take the small telescope and use the projection method to the event.

Use the lowest power eyepiece and project the image of the sun on to a white piece of cardboard, at least 8 inches from the eyepiece.

Never look directly into the eyepiece; project the image on to the cardboard.

This technique is great for large groups of adults or children as they can view the sun in a safe mode on the screen.

More advanced observers will have special solar telescopes to view the sun directly.

The transits of Mercury have a great relation to how we know just how far Earth is from the sun and there is much history behind this story.

Here and here is some interesting history relating to the Mercury transits of the sun.

If you miss this Mercury transit, the next event will occur Nov. 13, 2032, but will not be visible in the U.S., mainly on the other side of Earth.

Following that, the next decent Mercury transit, visible in the western hemisphere, will occur on Nov. 7, 2039!

The planet Venus tops the list as far as the rarest of transits, as Venus will transit the sun eight years apart and return again in some 121- year intervals.

The last Venus transits occurred back on June 5, 2004 and June 2012, with the next one occurring on Dec. 11, 2117.

Transits of Venus have a rich history.

So, get set for the rare Mercury transit next Monday.

To print your own monthly star chart, click here.

To view satellites/dates/times of passage, click here.

Listen to the Dr. Sky Show on KTAR News 92.3 FM every Saturday morning at 3 a.m.

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