Highland Road Park Observatory


Monday, 9 May from 6:00 am to 2:00 pm
First one in ten years!
No admission fee. For all ages.

A “transit” is the phenomenon of viewing a smaller body crossing in front of a larger one. On 9 May, for the first time in ten years, the disk of Mercury☿ will traverse the disk of the Sun☉.

A Transit of Mercury☿ is not visible to the unaided eye. At least 30x magnification is needed to easily see the phenomenon. Several telescopes (at least six) will be in operation on HRPO grounds.

HRPO will be open for the duration of the event. The Sun☉ will actually be rising here in Baton Rouge as the transit gets started!

Viewing a Transit across the Sun☉ can be dangerous for one’s eyesight if not performed correctly. The BRAS Forum thread lists a number of safe ways to view the transit (and actually, to view the Sun☉ in general). Do not use sunglasses, do not attempt to use your hand to cover a portion of the Sun☉, and do not attempt to “glance quickly” in the direction of the Sun☉. At any rate, a Transit of Mercury☿ is not visible to the unaided eye.

If a first-timer is in any doubt whether he will be performing the viewing safely, viewing of the Transit should be attempted only with someone with previous solar viewing experience.

Solar viewing glasses

Solar glasses, like the ones in use in the photo above, are for sale at this time from the HRPO at $2.00 per pair. If an adult patron requests by phone only (768-9948), we can hold one or two pairs of glasses for up to twenty-four hours. Keep in mind, the glasses will assist in seeing the actual size of the Sun in the sky, to compare with what is seen in a telescope. The glasses will not show the disk of Mercury, which is too small to see without magnification. Do not use the glasses with any magnification device.


Science Academy: Mercury☿…Saturday 16 April, 10:00 am to 12:00 pm
The swiftest planet is also the hardest to spot in the sky. Why? Cadets will investigate the origin of Mercury’s☿ largest features and how they were named. Cadets will also learn how to safely view the Transit of Mercury☿. (This program is for eight- to twelve-year-olds. The fee is five dollars per in-parish child and six dollars per out-of-parish child. Limit sixteen.)

Mercury☿ Viewing…Saturday 16 April, 6:00 pm to 7:30 pm and Saturday 23 April, 5:45 pm to 7:15 pm
The little and elusive scorching-and-freezing planet is in crescent phase in the constellation Aries♈ during these two early evening sessions dedicated to spotting it! A non-transit view of the planet can assist a comprehension of how diminutive an amount of sky it occupies. (There is no admission fee.)

Friday Night Lecture Series: Transits…Friday 29 April, 7:30 pm to 8:30 pm
The beauty of a transit is unlike any other celestial phenomenon. Come discover the history of these events, how to safely view one and what to expect for the upcoming Transit of Mercury☿! (The program is meant for high schoolers and adults. There is no admission fee.)

2012 Transit of Venus

The 2012 Transit of Venus attracted one of the largest crowds in HRPO history.

2012 Transit of Venus
2012 Transit of Venus
2012 Transit of Venus
2012 Transit of Venus
2012 Transit of Venus

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Updated by Frederick J. Barnett on Tuesday, April 5, 2016, 04:09 PM.