The Egyptian city of Luxor will plunge into daytime darkness for six minutes and 23 seconds on August 2, 2027, during a total solar eclipse that NASA says will be the longest anywhere on Earth until 2114.
The eclipse will darken the sun across parts of North Africa, Europe and the Middle East, but the longest duration of totality will be visible near Luxor, in southern Egypt. It will be the second-longest total eclipse of the 21st century, behind only the eclipse of July 2009, whose point of maximum totality fell over the Pacific Ocean, hundreds of kilometers southeast of the Japanese coast.
Luxor, often described as the world's largest open-air museum for its tombs, temples and monuments, sits on the site of the ancient city of Thebes and is flanked by the Valley of the Kings and the Valley of the Queens. The city will see the longest total solar eclipse observed from land anywhere since 1991.
Roger Davies, a professor of astrophysics at the University of Oxford, told CNN that six minutes and 23 seconds is a long time, and that people's eyes will adjust to the darkness. He said that normally only a few planets and the two brightest stars are visible during an eclipse, but that he hoped observers in Luxor would be able to see much more.
Chasing clear skies
Luxor also offers a strong chance of clear skies. Canadian meteorologist Jay Anderson, creator of the eclipse-tracking website Eclipsophile, said dust carried in from the Arabian and Saharan deserts is a potential problem, but that the region has minimal cloud cover in summer.
Heat will be a bigger factor. Temperatures will drop during the eclipse but will remain far below the peak of Luxor's summer, when daytime highs regularly top 41C (105F). Anderson warned that prolonged exposure to such heat can degrade the performance of modern camera equipment, not to mention pose risks to the people operating it.
The partial eclipse is expected to begin near the city just after 11:40am local time, with maximum totality at 1:05pm.
Crowds and rising prices
Davies has already secured a prime viewing spot for next year's eclipse, likely from the balcony or terrace of an air-conditioned hotel, as part of one of the many tour packages built around the event. But he fears many other travelers will be disappointed.
That is because the biggest obstacle for skywatchers hoping to witness the rare eclipse may not be clouds or dust, but other observers. Davies warned that potentially millions of people could gather within a relatively narrow geographic band to watch the eclipse, which could lead to packed hotels and congested roads.
Hotel prices in Iceland and Spain rose 98% and 135% respectively ahead of last week's eclipse, The Independent reported. According to Booking.com, more than 90% of Luxor accommodations that could be booked on the platform during next year's eclipse are already unavailable, and many of the remaining hotels cost more than £2,000 ($2,695) for a single night.
The nine-day tour Davies is supporting, with prices starting at £4,950 ($6,600), is fully booked, as is a week-long program organized by the Harvard Alumni Association. Starting at $26,950 per person, that program will fly groups from London to Luxor via Giza on a private jet, with stays at five-star hotels.
Astrotourism in Africa
For the rest of the continent, the eclipse is expected to further boost Africa's growing reputation as a leading astrotourism destination.
Worsening light pollution means a third of the world's population, including 80% of North Americans, cannot see the Milky Way, while more than 99% of people in the United States and Europe live under light-polluted skies, according to a 2016 study. The three least affected countries, Chad, the Central African Republic and Madagascar, are all in Africa, the study found.
Namibia and South Africa are among the countries that have positioned themselves as flagship astrotourism destinations, each home to sites certified by DarkSky, a nonprofit organization that campaigns against light pollution. In South Africa's Karoo desert region, the night sky is so clear that solar systems roughly 2.5 million light-years away are visible without a telescope.
Davies said you can see the Andromeda Nebula, the giant galaxy closest to the Milky Way, with your own eyes there. He called it one of the darkest places he has ever visited, adding that he has been to many observatories.
Africa's eclipse history
The continent has a rich history with eclipses. In 1919, British astronomer Arthur Eddington led a team to the island of Principe, off West Africa, to photograph a total solar eclipse. The images later helped confirm Albert Einstein's theory of relativity by capturing how starlight bent as it passed near the sun's gravity.
In 1973, North Africa was the stage for a bold scientific mission, when researchers boarded the Concorde 001 to chase the moon's shadow over the Tropic of Cancer at 2,172 kilometers per hour. The supersonic jet's speed let the team stretch totality from seven minutes to 74 minutes, setting a record for the longest observation of a total solar eclipse in history that still stands.
More recently, skywatchers in southern and central Africa saw a "ring of fire" in 2016, when the sun's circumference blazed around the edges of the moon during an annular solar eclipse.
Egypt's astronomers prepare
For Egypt's astronomers, next year's long blackout cannot come soon enough. The Cairo-based National Research Institute of Astronomy and Geophysics (NRIAG) is the oldest research institute in North Africa and is home to what is considered the largest telescope in the Arab world, the Kottamia Astronomical Observatory.
Cairo will sit outside the path of totality on the day of the eclipse, with a partial eclipse obscuring 94% of the sun there. The 50-tonne telescope will still be pointed at the sky as part of a wide-ranging research program, said Ashraf Shaker, head of the astronomy department at NRIAG.
Shaker told CNN that the whole world needs to come, both as tourists and as scientists.
