Did you know that the current age of the universe is 13.8 billion years? A useful instrument for visualizing the chronology and age of the universe is the cosmic calendar. With this cosmic calendar scale, the big bang takes place on January 1 at midnight and there are 37.8 million years per day. This is a great way of easing the visualization of the age and chronology of our universe!
I think that it’s absolutely fascinating to think and learn about the vast size and scale of the universe. Everybody’s been told that their problems aren’t important in the grand scheme of things and while getting a C on a test might ruin your day, your life probably isn’t going to change course because of it. But it is absolutely fascinating to me to take this a few steps further.
Expanding your view exponentially to everything going wrong right now in the city you live in changes the relevant discussion from a bad grade to something like the amount of debt that Nashville is in, a topic that my roommate and I just randomly discussed. Expanding your view again to the country you’re in or even the entire planet can make your life feel entirely irrelevant and unimportant. While in the grand scheme of things, you’re still just a speck of dust on a planet that is even tiny compared to other planets in our solar system as in the graphic below, you cannot lose sight of the meaning of your individual life. That said, the universe is so much bigger than even our solar system so we’re likely even smaller than we had initially thought.
Thank you for reading my musings on how unimportant we each are in the grand scheme of things. I hope it wasn’t too overwhelming.
Unlike the usual Moon, during a total lunar eclipse, the Moon looks dim and red. This makes the Moon look evil, so ancient people were very afraid of the red Moon. When Columbus and his crew were trapped on Jamaica, many of his crew died of hunger because the natives didn’t help them search for food. Columbus predicted that a lunar eclipse was coming, so he told the unfriendly Jamaicans, “The Christian god is very unhappy now because you didn’t help us get any food.” When the Moon turned red, the Jamaicans howled and ran with ships of food from every direction.
So why does the Moon turn red? The Moon turns red due to a total lunar eclipse. When we learn that a lunar eclipse takes place when the Earth’s shadow falls on the Moon, we infer by intuition that during a lunar eclipse, we will not be able to see the Moon because the Earth blocks sunlight from shining upon it. However, this is not the case. When a total lunar eclipse takes place, because the Earth’s atmosphere bends and refracts light, some of the sunlight from the Earth’s sunrises and sunsets will be projected upon the Moon’s surface, causing it to look dim and red.
Therefore, theoretically, how dark the Moon looks during a lunar eclipse can reflect how much pollution we have. When there is heavy pollution, there will be many particles floating in the atmosphere. This partially keeps the light on Earth from getting to the Moon, causing the Moon to look darker than usual.
When we understand why the Moon turns red, the red Moon can be very exciting and spectacular to watch. During the MLK’s day last year, a blood moon happened with a super moon and the Whole Wolf Moon, so people also called it “Super Blood Wolf Moon”. However, don’t be distressed if you missed it. The next blood moon will take place on May 26, 2021. It will be great if we can watch it together!
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Let’s just imagine for a moment that humanity eventually advances in technology such that light-speed travel is attainable. The speed of light, roughly 3×10^8 m/s, is the upper limit on travel speed- If light could go any faster, it would.
With light-speed travel, humanity will likely attempt to colonize other planets, for a variety of reasons- curiosity, resource depletion, or even a sense of manifest destiny. Imagine, for a moment, that you are hoping to travel to a habitable planet in the Andromeda galaxy. Andromeda is 2 million light years away. This means that, even if a method of light-speed travel is devised, it would take 2 million years to reach a planet in one of the galaxies nearest to us. For reference, humans have been around for about two hundred thousand years.
Even with an endlessly vast universe, the chances of humans leaving the Milky Way seem to be essentially zero.
Up until the early 20th century, the laws that our universe abided by were best described by Isaac Newton in his Philosophiae naturalis principia mathematica. Newton’s principles still hold true for the most part, as they are the basis of many introductory classical mechanics classes today. Despite being able to model the laws of our universe for the most part, they began to break down when used to describe large-scale phenomena. German Physicist Albert Einstein wanted a model that could describe the laws of the universe in their entirety, so he produced the theory of general relativity, which he published in 1915. One key aspect of the theory of general relativity is that space and time are interwoven and form what is known as the fabric of space-time, which can be warped by massive objects. Because of this, general relativity states that light should be bent when it passes through distorted space-time around these massive objects. The apparent, or observed position of a star may not be its actual location if it is in the background of a much larger object.
Because of limits in technology, the only object large and near enough to use to observe this phenomena was the Sun. The Sun is too bright to be able to observe any stars in the background, but a total solar eclipse on May 29th of 1919 was the perfect opportunity to observe these background stars. Astronomers who conducted the observations knew the actual positions of the stars that were behind the sun during the eclipse. The eclipse lasted for long enough for astronomers to observe that these stars appeared ever so slightly away from their actual locations, but the observations were enough evidence to confirm Einstein’s theory of general relativity.
General relativity has yet to be superseded by a better theory, and for the time being best describes the nature of our universe. Had it not been for this eclipse, one can wonder how long it would have taken general relativity to be confirmed, or if it was even capable of gaining the support of other physicists at the time.
The Moon is tidally locked to the Earth, which means that we always see the same side of the Moon. People have come to call the side of the moon that we do not see the “dark side” of the Moon, as they think that this side never sees the sun and that the Moon’s phases are the result of the Earth’s shadow on the Moon. However, this is a common misconception. The phases of the Moon are not caused by the Earth blocking part of the Sun’s light. They are actually a result of the Moon’s position in its orbit around the Earth. Sunlight hits the Earth and Moon from the same direction, and they are both always half lit. The orbiting bodies’ relative positions to each other cause us to see different amounts of this light, creating the phases. Depending on its location in its orbit around the Earth, the Moon appears to be full, new, waxing, or waning. So, the “dark side” of the Moon is not really dark all of the time. In fact, it is only fully dark during what we call a full moon. The picture above shows the Moon’s “dark side” almost fully lit as it orbits around the Earth. So, the “dark side” of the Moon is not an accurate name. Something like the “back side” or the “other side” may be better when referring to the side of the Moon that we do not see.
This picture is a screenshot of the night sky view on January 19th, 2020 over Nashville through the lens of Star Atlas. Star Atlas is a website that allows anyone across the world to see the names and locations of various stars and planets they might see in the sky. In addition to a night mode, the site also features a day time view of the sky. I decided to use Star Atlas to see if I could identify any stars in the sky this evening since it was such a clear day. I was easily able to identify a few of the marked stars and Venus. The site also allows you to click on a particular star, planet, or other object and see the estimated distance and magnitude. I found it very interesting to look into these numbers as it helped me create a three-dimensional view of the solar system. I would recommend checking it out if you have some free time on a clear night.
Light speed travel has been a staple of popular culture for years. I first became aware of the idea of light speed from watching Star Wars as a kid. But would we ever be able to actually travel at the speed of light? What would happen if we were able to achieve light speed travel?
First of all, traveling at the speed of light is most likely impossible. Because of Einstein’s famous equation E=mc^2, we know that energy and mass can be converted into each other. As the energy of an item increases because of its speed, its mass will also increase. Because of this, as an item gets closer to the speed of light, the item’s mass will approach infinity. Since its mass approaches infinity, the energy required to move it will also approach infinity, making it impossible to travel at the speed of light.
What would happen if we could get close to the speed of light? One thing that would change is our perception of time. If someone could travel at 90% of the speed of light, time for that person would be halved compared to someone observing from Earth. Another noticeable change would be your field of view. Someone traveling at close to the speed of light would experience serious tunnel vision due to a phenomenon known as Aberration. You would experience Aberration because the photons would appear to be coming from in front of you. You would also experience the Doppler Effect, where light waves crowd together, creating the blue color seen in a number of science fiction movies.
Even though the light speed travel from science fiction is impossible, traveling close to the speed of light would be a mind bending experience. For more in depth reading on the speed of light, check out this article on How Stuff Works.
From Chapter 2, we learned about how the zodiac symbols are derived from the constellations that are along the ecliptic. As the Earth orbits around the sun, different constellations are visible. The Babylonians set the zodiac signs over 3,000 years ago in correlation with their 12 month calendar. While we still use the same time frame for determining things such as your zodiac sign, it is no longer accurate. The sky as we see it is different than the sky the Babylonians due to a shift in the Earth’s axis (North Pole). It does not point in the same celestial direction that it once did, so while you might think you are a Sagittarius, you might be a Capricorn instead!
This past spring I interned at a company that developed educational documentaries about interesting topics such as nature, history, and space. The owner of this company had a history of creating planetarium footage, and he managed a successful YouTube channel called SpaceRip. This channel compiles fascinating footage of our solar system and explains many of the little known intricacies regarding the universe. For one of my first jobs, I was told to make a video about The Hubble Legacy Field, the picture seen above.
The image may look at first like an ordinary still frame of our universe from a powerful telescope, however it really represents so much more. It is the pinnacle of all telescope discovery to this point in time. The one photo is a compilation of thousands of exposures captured over decades by the legendary Hubble Telescope. It shows approximately 265,000 galaxies that date back up to 13 billion years. So, by looking at this single image on your computer screen, you are not only witnessing the farthest depths of the universe humans have yet to reach, but you are also traveling back in time to the beginning of our universe as we know it. Though this photo represents the end of an era in its accumulation of all Hubble data, the new James Webb telescope will have far stronger capabilities in the coming years. If you would like to learn more about the Hubble Legacy Field, feel free to watch my video on Spacerip’s YouTube channel!
