When Night Falls at Midday
BY AWAKE! WRITERS IN ANGOLA AND ZAMBIA
‘NIGHTFALL at midday? Impossible!’ some might say. It is not only possible but happens several times every decade—whenever there is a total solar eclipse. What causes a solar eclipse, and why is it such a spectacular sight? The answer starts with the moon.
Are you familiar with the way the moon changes in appearance as it orbits the earth? When the moon and the sun are at opposite ends of the sky, we see what we call a full moon rising in the east as the sun sets in the west. As the days pass, the moon rises later each night, gradually making its way across the sky toward the rising sun. The illuminated portion of the moon gets progressively smaller, eventually becoming a mere crescent. When the moon shares the sky with the sun all day, even that crescent vanishes and the moon, with its dark side facing the earth, is virtually invisible. This is called a new moon. Then the process reverses, with the moon drawing away from the sun and finally returning to full. This cycle repeats approximately every 28 days.
The key to a solar eclipse is the new moon. Usually it simply passes by the sun in the daylight sky without our knowledge because the orbits are not in the same plane. On occasion, though, the sun, moon, and earth line up just right. Then, the shadow of the moon falls across the surface of the earth, causing an eclipse.
Solar eclipses result from a unique relationship between the sun, the moon, and the earth. The sun is tremendous in size, with a diameter about 400 times that of the moon. Remarkably, though, the sun is about 400 times farther away from us than the moon is. As a result, from our viewpoint the sun and the moon appear to be nearly identical in size. Thus, the moon can at times appear to fit perfectly over the sun.
In order for such a total solar eclipse to occur, the sun, the moon, and the earth must not only align precisely but they must also do so when the moon is at that part of its orbit that is close to the earth.* On these occasions the tip of the moon’s cone-shaped shadow produces darkness along a narrow strip of the earth’s surface.
In the case of the total eclipse of June 21, 2001, the shadow was to be as much as 120 miles [200 km] wide. The path of darkness was to begin at sunrise off the eastern coast of South America and pass across the South Atlantic, where its maximum duration of nearly five minutes would be reached. After traversing Angola, Zambia, Zimbabwe, and Mozambique, it would end at sunset off the east coast of Madagascar. Let us see how this celestial spectacle appeared to observers in Angola and Zambia.
Preparations for the Event
With high expectations, professional researchers, amateur astronomers, and many others flocked to Africa for this first total eclipse of the new millennium. As Lusaka, Zambia, was the only capital city in the path of the eclipse, many visitors headed there to observe it.
This was perhaps the biggest tourist attraction Zambia has ever enjoyed. Just a few days prior to the eclipse, Lusaka was flooded with thousands of visitors. Preparations for the event had been made months in advance. Hotels, lodges, campsites, and private homes were all fully booked, accommodating the hordes of visitors.
Public viewing sites included the Lusaka airport, where visitors could arrive in the morning, observe the event, and then depart in the evening. For weeks television and radio stations announced the forthcoming spectacle, repeatedly warning of the dangers of looking directly at the sun. Sales of special viewing glasses exceeded all expectations, and many shops sold out.
However, the eclipse was to touch the African continent first in Angola, at the coastal town of Sumbe. It was here that observers would experience a total eclipse of four and a half minutes, the longest duration over land.
Months prior to the eclipse, billboards announcing the eclipse and warning of its dangers were put up in Angola’s capital city, Luanda, and in other major towns. The moon’s shadow was to pass through the middle of the country, so all of Angola would see at least a deep partial eclipse. Luanda would see 96 percent of the sun’s disk covered. The government, in cooperation with private companies, arranged to import millions of special solar glasses for distribution. Many were given free to the disadvantaged.
The center of Angola’s eclipse activities was Sumbe, situated on a beautiful narrow coastal plain between the South Atlantic and the Angolan central plateau. The Sumbe area has escaped the worst of the conflicts that have ravaged Angola, so visitors find an intact town of approximately 25,000 residents, who are warm, friendly, and outgoing. To accommodate all the visitors, additional tourist facilities were prepared, and improvements were made to the local power system. A special eclipse workshop was arranged for scientists, government ministers, and humanitarian workers from Angola and other countries. A large stage was erected on the beach for an entertainment program on a scale never before seen in Sumbe.
The Big Day Arrives
One of the benefits of observing the eclipse from Angola was that in June the weather is quite dry. But imagine the dismay when, the day before the eclipse, clouds rolled into the Sumbe area! All evening and into the next morning, the town was shrouded in a thick cloud blanket. Would all the hopes of witnessing the eclipse be disappointed? By midmorning the clouds began to part, and by late morning the sky was blue and cloudless. What a relief! Similarly, there was concern in Zambia, as the dawn light revealed a hazy, clouded sky. But there too the view cleared just in time. Listen as eyewitnesses describe the events as they unfold.
Angola: “We chose to observe the eclipse from a prominent spot overlooking the sea. As the hour approached, throngs gathered on the town beach and in the viewing areas set aside for watching the event. At noon, when the eclipse was about to start, many donned their protective glasses and began looking for the moon’s first ‘bite’ from the solar disk. Shortly after noon the eclipse began. Through binoculars or a telescope, several sunspots—dark splotches on the sun’s surface—were visible. Watchers saw these spots engulfed in shadow one by one. As the eclipse progressed, the temperature dropped noticeably and the light began to take on an eerie color. Finally, as the last crescent of sun yielded to the advancing shadow, darkness fell.”
Zambia: “Located in Makeni, Lusaka, the Zambia branch office of Jehovah’s Witnesses was almost ideally placed for viewing the total eclipse of the sun. At 3:07 p.m., the moon began to block out the sun. Shadow bands swept across building walls, giving the effect of ripples of light. The wind subsided, and birds fell silent. The wildlife started to prepare for a night’s sleep. At 3:09 p.m., a few seconds before totality, the sun’s vanishing disk was reduced to a few glittering points of light, then just one. These phenomena are known as Baily’s beads and the diamond ring respectively.* Next followed a view of the chromosphere, a pinkish-red flash, leading to totality and darkness!”
Angola: “The dazzling diamond ring effect raised gasps and shouts. Then, at 1:48 p.m. local time, totality began. Reactions were quite varied. Some were engrossed in taking pictures. Others started shouting in unison, ‘Total! Total! Total!’ Still others began whistling and crying out in amazement as night fell at midday. Streamers of the sun’s million-degree atmosphere appeared to flow out in all directions to form the corona. We could see arches of flaming gas around the moon’s dark perimeter. Suddenly, as though time had leapt forward, the totality was over and a ray of sunlight blazed from the other side of the shadow.
“As the solar disk started to emerge, we saw the sunspots, previously devoured, emerging one by one from the darkness as the familiar circular shape of the sun was slowly restored.”
Zambia: “The period of the total eclipse here lasted for 3 minutes and 14 seconds, so there was time to absorb the awe of the event. It was dark, but there was a twilight glow around the horizon. Though still blue, the sky revealed planets usually obscured by the sun—Jupiter and Saturn, for example, were clearly visible points of light. Perhaps the most spectacular aspect of the eclipse was the sun’s corona. It appeared as a pinkish-white glow around a black disk. Mesmerized, observers described it as ‘simply amazing, magnificent.’ Gradually the disk of the moon slid aside, baring more and more of the sun’s face and allowing the sun’s rays to reach the earth unimpeded. By 4:28 p.m., the eclipse was over!”
Lessons From the Eclipse
Afterward, many remarked about the soul-stirring effect the experience had on them. In Angola one woman said that she was nearly moved to tears. Another reflected on the beautiful gift God had provided. Yet another noted that only a loving Creator would provide this spectacle so that people could appreciate the incredible beauty of earth’s power source.
It was clear that many people in Africa have great respect for the Creator and the Bible. As Jehovah’s Witnesses in the town of Sumbe spoke to others about the eclipse and noted that this was but one of the marvelous works of Jehovah, our Creator, the residents displayed a real interest in discussing the matter. Many enthusiastically accepted copies of a recent Watchtower magazine dealing with these marvelous works.
This celestial event helped millions of people to forget their problems for a few brief minutes and focus on something truly uplifting and awe-inspiring. Having seen glorious features of the sun that are normally invisible, some thought about the unseen but even more marvelous glory of its Creator, Jehovah God.
Since the orbits of the moon and the earth are elliptic, the apparent size of the sun and the moon vary a little according to where they are in their orbits. When the moon is at the point in its orbit farthest from the earth, the darkest part of the moon’s shadow may not quite reach the surface of the earth. When this occurs, observers on earth who are in line with that shadow experience an annular eclipse, with the sun visible as a bright ring around a dark shadow.
The effect known as Baily’s beads is caused by the sunlight passing through the lunar valleys just before totality. The expression “diamond ring” describes the appearance of the sun just before totality, when a tiny part of the sun is still exposed, giving the appearance of a white ring with a bright sparkle, similar to that of a diamond ring.
[Diagram on page 21]
(For fully formatted text, see publication)
Sun → Moon ⇨ Dark zone ⇨ Earth
© 1998 Visual Language
[Pictures on page 23]
Courtesy Juan Carlos Casado, www.skylook.net
[Picture on page 23]
Eclipse observers in Lusaka, Zambia