Can we see the point where the Big Bang occurred?
-Donald B.
Yes and no.
First, look in front of you. Now, look behind you. Next, look down the street. Finally, look through a telescope toward, let's say, the Andromeda Galaxy. The Big Bang happened at all those points. What you're asking, though, is can astronomers pinpoint a specific point in space in which the Big Bang happened? The answer to that question is no, because such a point doesn't exist. According to the prevailing cosmological theory, the Universe formed out of a singular event dubbed the Big Bang. Everything was created in that event, including energy, matter, space and time. A complete nothing. In fact, one cannot even say that "nothing existed before the Big Bang" because the word "before" is temporally relative.
The Big Bang region is everywhere and also nowhere.
Because the moon is moving away from Earth, will solar and lunar eclipses ever stop?
We will address this question in two parts:
SOLAR ECLIPSES
The moon is moving away from Earth at a speed of about 4 cm per year, the same rate at which fingernails grow. Although the moon's distance from Earth won't increase substantially over a human lifetime, the cumulative effect over millions of years will be substantial..
In approximately 600 million years, the moon's distance will have increased enough to make it always appear smaller in the sky than the Sun. Consequently, no more total solar eclipses will occur. Instead, Earth will experience only annular solar eclipses: those in which the moon doesn't entirely block the Sun so that a "ring of light" is visible around the darkened moon.
Total solar eclipses will stop in about 600 million years. After that time, the moon will appear smaller in the sky than the Sun. Consequently, when the moon crosses directly in front of the Sun, an annular eclipse will occur.
LUNAR ECLIPSES
Lunar eclipses occur when the full moon moves into Earth's shadow cone. This cone extends for approximately 840.000 miles. By the time the Sun's life cycle ends in more than five billion years, the moon will not have moved even close to the end of this cone: less than half the distances, actually. Lunar eclipses will continue to happen throughout the remainder of Earth's life.
The Universe is expanding all the time. Does that mean that I am expanding, too, and not just in the conventional sense?
-S.S.
The Universal expansion causes distant galaxies to recede from the Milky Way. Or, more correctly, to appear to recede from the Milky Way. In fact, all the galaxies are moving away from each other as a consequence of the expansion. However, this expansion is not observable at smaller scales, such as at the level of the human being, because local forces are far stronger. The electromagnetic forces within the body easily overpower such expansion. Even the gravitational attraction between close galaxies, such as the Milky Way and Andromeda, is stronger than the Universal expansion. Consequently, these galaxies are moving toward each other at 300,000 miles per hour and will collide in 4 - 6 billion years.
I heard that the Arecibo Radio Telescope collapsed. Will that affect the Arecibo Radio message to the M13 Globular Cluster? -C. Davis
We should first provide some background.
The Arecibo Radio Telescope, located in Puerto Rico, was the largest radio telescope in the world. However, toward the end of 2020, the receiver platform collapsed into the dish, rendering it inoperable.
In 1974, astronomers beamed a "message" toward M13, a globular cluster in the constellation Hercules. Consisting of 1,679 bytes of data, this message contains information about humanity, the solar system, our number system, our basic chemical constituents, and even the radio telescope that sent the message. The astronomers used 1,679 bytes because 1,679 is a semi-prime number, meaning that iit is the product of two prime numbers, in this case 23 and 73. When those bytes are arranged in 23 columns and 73 rows, the following image appears:
The message is en route to the M13 Globular cluster, which is approximately 25,000 light years away. At this moment, the beam continues toward its destination. Despite the passage of almost fifty years since the transmission, it has only traveled 0.18% of the entire distance. Although the Arecibo Radio Dish is now defunct, the message it sent will continue to move toward M13. The telescope's destruction will not affect this transmission at all.
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