UPDATE: The Transit of Mercury program planned for Edgewater Park has been canceled due to a forecast of clouds, rain/snow, and below freezing temps. We’ll have to try again in 13 years when the next transit comes around.
The planet Mercury will cross between Earth and Sun on Monday, November 11, 2019. Given clear skies, members of the Cuyahoga Astronomical Association (CAA) will be stationed at the lower level of Edgewater Park offering safe viewing of the event. Viewing times at Edgewater will be from noon until just after 1:00 p.m.
CAA members will be present with their solar-safe telescopes offering several ways of viewing our Sun. Cloudy skies will, of course, cancel the event. No tickets or reservations are required; those interested should simply come to the park. The transit is a natural, astronomical occurrence and cannot be rescheduled; when it has finished, it is finished!
Anyone with eclipse viewing glasses would be able to view the transit but without the magnification offered by a telescope, the event will be hard to see. Mercury, officially a planet, is not quite three times the size of Earth’s Moon. Viewed from Earth, around 48 million miles distant, Mercury is tiny!
The 2019 transit begins at about 7:35 a.m. and will end at 1:04 p.m. November 11. Another transit of Mercury won’t take place for 13 years.
WARNING: NEVER look directly at the sun through binoculars, a telescope, or with your unaided eye. Permanent eye damage and even blindness can result. Astronomers use special filters and glasses to safely observe the sun. Sunglasses, photo negatives, etc. will not protect against eye injury.
For the second time in history, a human-made object has reached the space between the stars. NASA’s Voyager 2 probe now has exited the heliosphere – the protective bubble of particles and magnetic fields created by the Sun.
Comparing data from different instruments aboard the trailblazing spacecraft, mission scientists determined the probe crossed the outer edge of the heliosphere on Nov. 5. This boundary, called the heliopause, is where the tenuous, hot solar wind meets the cold, dense interstellar medium. Its twin, Voyager 1, crossed this boundary in 2012, but Voyager 2 carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.
Voyager 2 now is slightly more than 11 billion miles (18 billion kilometers) from Earth. Mission operators still can communicate with Voyager 2 as it enters this new phase of its journey, but information – moving at the speed of light – takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.
The most compelling evidence of Voyager 2’s exit from the heliosphere came from its onboard Plasma Science Experiment (PLS), an instrument that stopped working on Voyager 1 in 1980, long before that probe crossed the heliopause. Until recently, the space surrounding Voyager 2 was filled predominantly with plasma flowing out from our Sun. This outflow, called the solar wind, creates a bubble – the heliosphere – that envelopes the planets in our solar system. The PLS uses the electrical current of the plasma to detect the speed, density, temperature, pressure and flux of the solar wind. The PLS aboard Voyager 2 observed a steep decline in the speed of the solar wind particles on Nov. 5. Since that date, the plasma instrument has observed no solar wind flow in the environment around Voyager 2, which makes mission scientists confident the probe has left the heliosphere.
“Working on Voyager makes me feel like an explorer, because everything we’re seeing is new,” said John Richardson, principal investigator for the PLS instrument and a principal research scientist at the Massachusetts Institute of Technology in Cambridge. “Even though Voyager 1 crossed the heliopause in 2012, it did so at a different place and a different time, and without the PLS data. So we’re still seeing things that no one has seen before.”
In addition to the plasma data, Voyager’s science team members have seen evidence from three other onboard instruments – the cosmic ray subsystem, the low energy charged particle instrument and the magnetometer – that is consistent with the conclusion that Voyager 2 has crossed the heliopause. Voyager’s team members are eager to continue to study the data from these other onboard instruments to get a clearer picture of the environment through which Voyager 2 is traveling.
“There is still a lot to learn about the region of interstellar space immediately beyond the heliopause,” said Ed Stone, Voyager project scientist based at Caltech in Pasadena, California.
“Voyager has a very special place for us in our heliophysics fleet,” said Nicola Fox, director of the Heliophysics Division at NASA Headquarters. “Our studies start at the Sun and extend out to everything the solar wind touches. To have the Voyagers sending back information about the edge of the Sun’s influence gives us an unprecedented glimpse of truly uncharted territory.”
While the probes have left the heliosphere, Voyager 1 and Voyager 2 have not yet left the solar system, and won’t be leaving anytime soon. The boundary of the solar system is considered to be beyond the outer edge of the Oort Cloud, a collection of small objects that are still under the influence of the Sun’s gravity. The width of the Oort Cloud is not known precisely, but it is estimated to begin at about 1,000 astronomical units (AU) from the Sun and to extend to about 100,000 AU. One AU is the distance from the Sun to Earth. It will take about 300 years for Voyager 2 to reach the inner edge of the Oort Cloud and possibly 30,000 years to fly beyond it.
This is a gallery of eclipse photographs made by members of the Cuyahoga Astronomical Association (CAA). Some members traveled to various places along the path of totality to experience the total solar eclipse. Some CAA members stayed behind, photographing the deep partial eclipse. We are fortunate to have a number of talented photographers and astrophotographers as members and pleased to be able to exhibit their amazing work here. We will add new images to this post as they are received so check back on occasion! Please note: these images are the property of their individual creators and may not be used without the photographer’s expressed permission.
The Cuyahoga Astronomical Association (CAA), in cooperation with Cleveland Metroparks, will host an Eclipse Watch event at Edgewater Park, on Cleveland’s western Lake Erie shore, from 12:30 to 4:00 PM, Monday, August 21. The event will be free and open to the public, no reservations required, to observe the day’s solar eclipse. In case of rain, the event will be canceled.
The Edgewater Eclipse Watch will include:
Telescopes equipped to safely view the eclipse, tended by CAA members
Eclipse viewing glasses provided by AstroZap, one per group, please!)
Non-profit organizations, including Cleveland Metroparks, with family activities.
Additional activities to be announced!
The venue for the Edgewater Eclipse Watch will be at the west end of Edgewater Park’s lower level parking lot (see map below). Telescopes and other activities will be in the grassy area adjacent to the parking lot. Visitors may come and go as they please during the event.
Millions of people will enjoy this eclipse of the Sun, some portion of which will be visible from everywhere in the continental United States; it’s even been dubbed “The Great American Eclipse” and “The National Eclipse.” Locations along a relatively narrow strip of land stretching from Oregon and the Pacific Northwest to the Atlantic off South Carolina will enjoy the full glory of a total solar eclipse. Here in Northeastern Ohio, we will see a deep partial eclipse with, at its peak, the Sun reduced to a brilliant crescent in our early afternoon sky.
A solar eclipse takes place when our Moon comes between Sun and Earth casting its shadow on Earth’s surface. The illustration below shows how the depth of Moon’s shadow varies depending upon how much of Sun is covered. The small black dot indicates the area where all of the solar disk is covered and where a total solar eclipse is in progress; outside of that dot, a large shaded area shows where various levels of partial coverage — the partial eclipse — is visible.
This video from NASA shows how eclipses work and why they don’t happen every month. Spoiler: Moon’s shadow “misses” the Earth most of the time…