In an incredibly rare occurrence the planet Mercury will be visible as it crosses the face of the Sun on Monday May 9.

While it would be a lie to claim that it’s a once in a lifetime event, Mercury passing across the Sun is rare enough to make it noteworthy, writes Clark Hughes for MLive.

Mercury To Cross Sun On May 9

Rare event excites stargazers

“It’s not that common,” said Mike Murray, planetarium manager and astronomer at the Delta College Planetarium in downtown Bay City. The planetarium is fully prepared for the event, and will invite the public to watch as Mercury transits the Sun.

Murray will have telescopes set up from 10AM to 2PM, with members of the public invited to come and watch the occasion. “It’s a really fun event,” Murray said.

The telescopes will be found on the observation deck, set up with special sun filters to protect your eyes.

Watch Mercury transit the Sun at various planetariums

For those in Flint, head to the Longway Planetarium. Manager Buddy Stark says that several telescopes will be available for members of the public to watch as Mercury crosses the Sun. The telescopes will be in position from 9AM until 2:30PM, or when the clouds cover the sun.

“We could probably handle 10-15 people at a time,” Stark said.

Space watchers can also take in the event at the Abrams Planetarium on the campus of Michigan State University in Lansing. The event will run from 8:30AM until Mercury is no longer visible, according to Planetarium Production Coordinator John French.

“If the weather is bad, we’ll live-stream on TVs in our lobby,” and a live simulation of the planet crossing the sun will be running in the planetarium said French, who also writes and edits MSU’s Sky Calendar.

Each of the aforementioned events is free to visitors.

NASA to provide live stream of event

French said that Mercury only ever passes across the Sun in May and November, when the orbits of the Earth and Mercury align. In fact it only happens approximately 12 times every 100 years.

“I know the last time we had a transit visible in Michigan was in November of 2006 and it was completely overcast,” French said. While May might be better for skygazing in Michigan, the next time Mercury will transit the Sun in May is in 2049.

If you want to observe the event it is probably best to get down to these events, or look for a similar one in your local area. You will be able to project an image of the Sun on a piece of paper using a pinhole viewer, but Mercury will appear as a tiny dot.

Murray says that making homemade sun filters is not advisable. He recommended the use of wielding goggles of shade No. 14 or darker, and no filter should be used in the eyepiece of a telescope.

In fact you will need a specially filtered telescope to see Mercury because the planet is so small. NASA says that Mercury will appear as a small black dot while it transits the Sun and moves into view at 7:12AM EDT.

It will move relatively slowly across the Sun, reaching the midpoint around 10:47AM and exiting at 2:42PM. In the eastern United States skygazers will be able to observe the whole 7.5 hour journey, assuming they have equipment which provides the correct magnification and a set of real solar filters.

The space agency NASA will provide a live broadcast from 10:30AM to 11:30AM EDT on NASA TV. You can also watch on the NASA Facebook page.

After May 9, Mercury will pass across the Sun again on November 11, 2019; November 13, 2032; November 7, 2039 and May 7, 2049.