A rare vision of tiny Mercury gliding across the molten face of the sun greets Monday morning in a cosmic pageant that won’t be seen again until 2032.
The journey of Mercury, the smallest planet in the solar system and nearest to the sun, begins at about 7:35 a.m. Eastern, traversing the sun’s face for more than five hours before exiting about 1:05 p.m.
While the trip cannot be watched by the naked eye, several webcasts are scheduled, and a handful of astronomy clubs are having events.
“The coolest thing for me is the historical signficance of transits,” said Padi Boyd, an astrophysicist with the NASA Goddard Space Flight Center. “Humans have been watching patterns in the sky for millennia. It allowed people to get the architecture of the solar system.”
While the next transit of Mercury may be in 2032, Boyd said people living in the U.S. won’t have an opportunity to see it again until 2049.
“It’s really the last time we’ll get a great view for 30 years,” she said.
The Virtual Telescope Project 2.0 is planning to broadcast the event live via a webcast. Watch at: https://www.virtualtelescope.eu/
NASA will have a nearly live webcast of the event. Watch at: https://mercurytransit.gsfc.nasa.gov/2019/.
Space.com expects to also host a web event with views from multiple telescopes. Watch at https://www.space.com/
“Never look at the sun through a telescope,” warned Bruce McClure in his column about the event for EarthSky.org. “Unless you are well-versed with the telescope and how to properly use solar filters, we advise you to seek out a public program via a nearby observatory or astronomy club.”
While Mercury’s trip across the sun is not the fireworks event of the 2017 total solar eclipse, it is a notable astronomical play that will showcase the moonless, rocky planet as a small black orb slipping across the giant orange circle of Earth’s nearest star.
Only Mercury and Venus can pass in front of the sun as seen from Earth, and Mercury’s transit only happens 13 to 14 times per century.
The last time was in May 2016. The next time following Monday will be Nov. 12, 2032.