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原作：Stephen James O'Meara
Translation: Wang Zhongwei
Proofreading: Huang Shixin
Choreographer: TN.
Backstage: Zhu Chenyu
Original link:https://www.astronomy.com/observing/our-ultimate-guide-to-the-eclipse/
The stunning corona can only be seen during a total solar eclipse. As you can see, this is a total solar eclipse on March 29, 2006. You have to stand in the path of a total solar eclipse to see this otherworldly sight, so plan accordingly.
图片来源:Alan Dyer
On April 8, 2024, there will be a total solar eclipse over North America. On this day, the Moon will move in front of the Sun, completely covering its bright surface. At that time, the shadow caused by the moon will obscure parts of Mexico, the adjacent United States and eastern Canada, plunging countless people into darkness for up to 4 minutes and 28 seconds, nearly 70 percent longer than the Great U.S. Solar Eclipse on August 21, 2017. In other words, we have plenty of time to enjoy this breathtaking celestial phenomenon.
If you've been on the path of a total solar eclipse during the 2017 solar eclipse and you've experienced this unparalleled feast firsthand, you won't need to see it again this April. But the following advice may help you, as no two eclipses in the world will be exactly the same. And for those who haven't experienced a total solar eclipse, this article will help you plan an unforgettable eclipse trip.
A total solar eclipse is one of the most magnificent and mysterious phenomena in the sky. Such extraterrestrial spectacles can keep awe and wonder in people's hearts for a long time. Add to that some bizarre and unique environmental effects, and you can imagine why a total solar eclipse is an experience like no other. No, don't imagine it. This April, do what you can to see this rare spectacle.
01
The most important thing
During a partial solar eclipse, you'll need to take appropriate eye protection, such as wearing safe eclipse goggles, as the author's wife, Deborah Carter, does, to watch the moon obscure the sun.
图源：Stephen James O'Meara
To see the total eclipse and experience the sensory feast that accompanies it, you must be on the path of the total eclipse (i.e., the path of the moon's inner shadow (umbra) through the Earth. If you weren't on this narrow 200-kilometre-wide path, you wouldn't see the moon completely covering the sun, you wouldn't be able to see the corona, and you wouldn't be able to experience the pomp and circumstance of complete darkness or all sorts of other peculiar atmospheric and environmental effects.
This fact cannot be overemphasized. Anyone outside the path of the total eclipse will be in the shallower outer shadow (penumbra) of the Moon and will only see a partial solar eclipse. Even if you stand in a 99% fitting eclipse zone, you won't be able to see the sun's outer crown, a layer of atmosphere as thin as a cicada's wings that is 1 million times dimmer than the sun's surface, and even the remaining 1% of sunlight will wipe it out of sight. (Don't be fooled by photos, which tend to exaggerate the brightness of the corona).
A total solar eclipse and a partial solar eclipse are quite different. As Annie Dillard pointed out in her 1982 book Teaching a Stone to Talk, "Chasing a partial solar eclipse is very interesting, but observing a total solar eclipse is a completely different feeling." The difference between them is like ...... Flying on a plane is the same as falling off an airplane. Although I watched the partial solar eclipse first, I still couldn't withstand the impact of the total solar eclipse. "
To fully understand this passage, you must stand on the path of a total solar eclipse. It's like watching a live performance, standing on the street outside the concert hall is more than half the same as sitting in the concert hall. Looking at a static photo of an eclipse won't surprise you as much as experiencing it yourself.
You will need to choose to watch the eclipse in the shadow (gray shaded area) where the Moon casts onto the Earth's surface. Only there can be a total solar eclipse, and only partial solar eclipses can be seen elsewhere.
Credit: Astronomy: Roen KellY, Topography: NASA/Jet Propulsion Laboratory
02
Location and weather
The first question most eclipse connoisseurs are asked is, "Where are you going to see the eclipse?" Why? Because they probably know where the weather is clear and they can see the total solar eclipse. When it comes to solar eclipses, location and weather are inextricably linked. Unfortunately, no one can predict with 100% accuracy where a total eclipse will be seen without being hindered by clouds. When choosing a location to watch the eclipse, keep in mind that while eclipse weather forecasts are usually accurate, any accident can happen. It's a good idea to plan ahead before you go.
As you read this, the most sunny spots on the path of the total eclipse (at least in the United States) will soon be filled with eclipse spectators. Accommodation at these locations can be very scarce or expensive. If you still want to watch the eclipse at these locations, it's best to avoid traveling to these locations the night before or on the day of the eclipse. The traffic jams that many people experienced during the total solar eclipse in August 2017 were nothing short of a nightmare. If you must travel at that time, be prepared for long delays on the road.
Some eclipse chasers want to avoid the crowds and choose to try their luck elsewhere. They will consider the weather, but they will also follow their heart. If the Total Eclipse Trail passes by or is close to a region of North America that you really want to visit, whether it's to enjoy the scenery, attend an event, or meet family and friends, then make North America part of your eclipse adventure. If you want to meet family or friends, you can share the experience with them and double the joy. Plus, if you're unlucky enough to get bad weather, you can still look forward to something else exciting. Whatever you decide, just make sure you're on the path of the total eclipse on the day of the eclipse.
If possible, arrive at your destination a few days before the eclipse so you have time to stare at satellite data and local weather reports. If the weather is bad for a few days, you still have time to start a backup plan. You just have to think about the time of the whole eclipse and the distance to your new destination, as well as the traffic jams. After watching the eclipse, it's April 8, which happens to be Monday, so if your trip is affected, you'll need to plan for travel delays.
Try to observe the eclipse from the centerline, which is the line between the north-south limits of the total eclipse path (the red line in the image above, or see the detailed map in the Atlas of Astronomy). The closer you are to the northern or southern boundary, the shorter the total eclipse time. The astronomical website where this article was published has detailed maps that give the time of the total eclipse at different locations away from the center line. If the weather is clear, don't miss these locations, and don't leave the Total Eclipse Trail.
As the eclipse progresses, you must keep an eye on the sky to assess whether bad weather, smoke, or even scattered clouds will interfere with your viewing of the total eclipse. If you encounter sudden dark clouds on the day of the eclipse, be prepared to travel to a clearer place. As long as you don't leave the total eclipse path and keep heading towards a sunny day.
图源：Stephen James O'Meara
If you have to travel to a clearer area from the location of your choice before the eclipse day, follow the same advice. Remember to fill up your car with gas and prepare plenty of food and water (enough for a full day or more of a trip) before the eclipse day. Note that during the 2017 solar eclipse, some gas stations in prime locations along the total eclipse path ran out of gas. Many stores are also running out of bottled water, so be sure to buy it well in advance. Keep a clear head along the way and make better judgments at all times. Remember, safety comes first.
On the day of the eclipse, please go to the observation site early, and it is recommended to arrive at least one hour before the partial eclipse begins. On the path of the total eclipse, you will observe all the partial eclipse phases, and the Moon will continue to eat away at the Sun until it is completely swallowed. This phase typically lasts around 90 minutes, giving you time to observe for cloud activity in the sky before the total eclipse arrives. If clouds begin to threaten visibility, make the decision to move to a new observation site before the eclipse is 50% over. That way, you'll have at least 45 minutes to look for a clearer spot. Just make sure that the direction you're heading in is on the path of the total solar eclipse.
If you have mottled clouds overhead, you may need to hit the road at any time, especially as a total solar eclipse approaches. Don't put all your attention on the clouds overhead, but also scan your surroundings, look for areas where the sun is shining, and head towards them. Look for a large clearing in the distance or a large gap in the clouds. Time is of the essence, so be prepared to act quickly. In cloudy conditions, be sure to pack your bags and be ready to go. Don't worry if the device isn't installed or malfunctioning, you don't need any equipment to watch the eclipse. All you need is a qualified solar filter to view a partial eclipse, and during a total eclipse you only need to use your eyes or binoculars to see it. (Solar filters must be worn at all stages except for the whole eclipse).
However, if you can't avoid the clouds in the sky, you can still experience the effects of a total eclipse. You can still see darkness fall, the corona illuminating the clouds, and many visual and physical changes.
Not all clouds will bring disaster to a total solar eclipse. This photo shows a partial solar eclipse taking place behind the clouds. A group of sunspots can be seen near the edge of the lunar disk.
Source: Alan Dyer
03
Make sure you can see the total solar eclipse
Let's say all goes well, today is the day of the eclipse, you arrive at your final destination, and the weather is clear. You've safely enjoyed a partial solar eclipse through a solar filter, and the total eclipse moment is just around the corner. When the moon is about to shade the last rays of sunlight, you'll probably find your heart pounding and throbbing.
Now, it's time to take a break and remind yourself of the second most important fact: you have to remove the solar filter to see a total solar eclipse.
You can't see the whole eclipse through a solar filter. During a partial solar eclipse, the sun is still visible, and you will definitely need a filter, but during a total solar eclipse, the moon completely blocks the sun. All you see is the dark side of the moon and the corona, which is harmless to the eyes.
Once you've removed your solar filter and started observing the total solar eclipse, try to restrain yourself and don't disturb others. In fact, you may find this suggestion redundant, because seeing the scene of the moon shadow surrounded like smoke by the corona makes the brain stop and allow the most primitive emotional impulses to fill our minds.
Here's the third and final fact: the most important thing is that you saw the total solar eclipse with the naked eye. Have you ever heard of Sperling's "eight-second rule"? It was proposed by Norm Sperling, the author of astronomy, who wrote in August 1980 that no matter how long a total solar eclipse lasts, the universe makes us feel that it is only eight seconds long. However, this time that passes in a hurry can make us feel an eternal, otherworldly tranquility. Don't use your camera to watch a total solar eclipse. Even if you take a photo, it can't compare to the experience in person. My advice is that you just follow the old Zen proverb: "Live in the moment, live to the extreme." "
Still hesitating?
If you're still hesitant to watch a total solar eclipse, think about this: The next total solar eclipse in the United States and Canada won't happen until August 23, 2044. Mexico's next total solar eclipse will not take place until March 30, 2052. As a life-changing experience, the wait is long enough.
If you're on a journey to chase a total solar eclipse this April, may the sky shine on you until darkness falls during the total eclipse.
04
Traffic problems to watch the eclipse
Severe traffic jams occurred immediately after the end of the "National Solar Eclipse" in August 2017, causing a sharp increase in people's return times. It's likely that this April will be the case again, or even worse than last time, so be prepared.
图 来源:Alexandragl/Dreamstime.com
A study after the total solar eclipse in August 2017 showed a significant increase in traffic flow in states along the route, peaking in the week before the total solar eclipse and after the total solar eclipse. (Many people who watched that eclipse may remember the nightmare they experienced when they returned home.) ）
Compared to 2017, this April's solar eclipse had a longer total eclipse. Millions more people live on this eclipse path, and the eclipse path passes through many large cities, making day trips easier for many people. All of this means that traffic is likely to be more congested this year than in 2017, especially in areas where the road system is unable to cope with heavy traffic.
It's crucial to keep this in mind, even if you're usually only a few hours away from your destination. As cities fill with people looking for a solar eclipse, the roads become busier for everyone. Even a week in advance may take longer than usual. Travel times may also increase in the hours leading up to the eclipse. Then, during the total eclipse, the number of cars on the road drops and rebounds after rounding.
No matter how far you're walking, expect to have a few extra hours than usual, especially when you're returning after a total solar eclipse. Make sure you have the proper supplies for long trips, including water, food, and medications that need to be taken on time. If you can, it's a good idea to stay after a total solar eclipse to watch a partial eclipse. Not only will you experience a "full" eclipse, but you'll also be able to wait for traffic to flow back up.
EDITOR IN CHARGE: DAIKIN
Shepherd New Media Editorial Department
Picture name: Open corona
图片来源 Peter Ward (Barden Ridge Observatory)