Blog 1

Posted on January 23, 2024 by James Bamshad

Imagine if the entire history of the universe could be squeezed into a single calendar year, providing a perspective of how much time has truly passed in this universe. Enter the cosmic calendar, a concept introduced by the astronomer Carl Sagan. Within the cosmic calendar, each month corresponds to over 1 billion years, allowing us to fully understand staggering age of the cosmos. To summarize and put things in simple terms, picture the Big Bang as the calendar’s January 1, and the emergence of Earth and life unfolding in the final moments of December 31. This detail, where life emerges in the final minutes of December 31st, emphasizes the recent appearance of humans relative to other events. As we move through the cosmic calendar, we witness the birth of stars, the formation of galaxies, and the unfolding drama of cosmic evolution over billions and billions of years.

Here are some more specifics, taken from the diagram below:

  • Modern humans evolved with 8 minutes left in the cosmic calendar.
  • The end of the last ice age came within the final minute of the cosmic calendar.
  • The cold war came with JUST .2 seconds left.

It’s a simple reminder that our presence is just a brief moment in the immense cosmic story.

Image Source

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The Vast Size and Scale of the Universe

Posted on January 23, 2024 by Thomas Shelton

BBC Science Focus

The Universe is also used as a reference point to display somethings enormity. “I love you more than anything in the world” is massively trumped by “I love you more than anything in the Universe.” But what does this really mean? How much can the universe really hold? How big is it REALLY? The Observable1 Universe itself is over 92 billion light years across. 92 BILLION!! For a brief scaling reference, just our Milky Way Galaxy (huge, by the way) is merely 100,000 light years across. Our Observable Universe is 920,000 times bigger than The Milky Way. Observed light from this far away could predate even the Milky Way itself. It would be 92 billion years old after all. With how advanced our science and technology is, even now it is hard to comprehend the sheer vastness of the Universe but it is a fascinating topic that I hope to learn more about.

  1. This is just obervable, who knows how much we do not know. ↩︎
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Blog 1 – Light Speed

Posted on January 22, 2024 by Jack Abrams

The speed of light is a fascinating topic that has significance from everyday life to the vast expanse of the cosmos. The speed of light is the speed at which light travels through a medium, and for a vacuum, this speed has been defined as 299,792,458 m/s. This speed is almost incomprehensible to us due to its magnitude. For example, if you moved at the speed of light, you would circumnavigate the equator approximately 7.5 times in one second.

Because of this finite speed, everything we observe is a glimpse into the past. This is particularly applicable to astronomy due to the vast distance of objects observed. Astronomers are able to use this principle and look further back in time by studying more distant objects. Our nearest neighbor, the Andromeda Galaxy, is 2 million light years away, meaning we see what it looked like 2 million years ago. This allows astronomers to garner a better understanding of the universe’s history.

Along with visible light, all forms of electromagnetic radiation travel at the speed of light. Therefore, this speed governs both the light viewed from distant stars on Earth, as well as communications with distant space probes. NASA’s Voyager 1 probe, the most distant satellite in interstellar space which was launched in 1977, takes nearly a day (22.5) hours for a transmission to reach the spacecraft. This delay is due to the spacecraft being more than 15 billion miles away from Earth, and the speed of light, or electromagnetic radiation in this case, sets the ultimate limit of the speed of these communications. This is even applicable to the communication delay during the Apollo missions, where it took 1.255 seconds for communications to reach the moon from Earth, as seen in the graphic below.

Speed of light from Earth’s surface to Moon’s surface
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It’s not a phase, Mom! ⋆⁺₊⋆ ☾⋆⁺₊⋆

Posted on January 22, 2024 by abbieychen

One thing I love about the nighttime is getting to see the different phases of the Moon in different times of its cycle. The Moon cycle consists of 8 phases as you can see in the picture below, and lasts 29.5 days, which is around one month! In this period, we see the Moon go from new moon (this is when the Moon is dark to us) as it waxes/increases up to full moon (a beautiful, completely round moon!), and then as the full moon wanes/decreases down to darkness. One side of the moon is always facing the Sun because sunlight hits Earth and Moon from the same direction. During different positions of the Moon’s orbit, we will see a different shape of light/dark on the moon. Although we see different phases, we always see the same face of the moon! This is because the Moon’s orbit around the Earth and its rotation around its axis take around the same time! We call this characteristic “synchronous rotation”, and it happens because of the Earth’s gravity affecting the moon.

A helpful visual of the moon phases! (Image credit: Karl Tate/Space.com)

A different perspective: if you were on the side of the moon facing Earth, you would see “phases” of the Earth that are the opposite of what Earth is seeing the Moon as! So if the Moon was in new moon phase, the view of the Earth from the Moon would be a “full Earth!”

One thing I learned from our textbook (“The Cosmic Perspective” ) that I didn’t realize before was that the phase of the Moon also determines what time of the day we get to see the moon. For example, a full moon rises at sunset and a first-quarter moon rises around noon. That also determines when it sets.

A beautiful first quarter moon in midday! (Image credit: stephaniesbecker@gmail.com)

No matter what, our Moon will always be there with us. Even when you don’t see her! (did you ever wonder why the Moon’s following you? it’s because the Moon is a significant distance away from us, and we can relate this to our knowledge on angular distance!) ☾ So, if you’ve read all the way down here, I would love to know what your favorite moon phase is! Mine would definitely be the full moon, because it makes the night so bright!! ⋆⁺₊⋆ ☾⋆⁺₊⋆

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Humans and Light Speed

Posted on January 22, 2024 by The Cosmic Traveler

by me

The speed of light is around 300,000,000 meters per second. It’s so fast that it can circle the Earth 7.5 times in one second. I always wondered if humans can ever achieve speeds the same as light, but we’ve only managed to go 176,462 meters per second with the Nasa Parker Solar Probe. More on that can be read here. But then again, can a human even handle moving at light speed? If pilots can get unconscious moving in fighter jets going at 222 to 388 meters per second, then it seems unlikely we’ll be able to handle 300,000,000 meters per second.

We always see in sci-fi movies and tv shows ships moving at the speed of light or even past it with no issues. This would be amazing to accomplish in real life. Being able to travel to different stars and planets in only in a matter of minutes or hours instead of billions of years. However, if we look at the current growth rate of our technologies, we still have years to centuries worth of growth to cover.

We can dream and we can hope to one day achieve these speeds, however it is not likely we will see this in our lifetimes.

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Blog 1 – Solstices, Equinoxes, and Seasons

Posted on January 22, 2024 by Julian Delamaza
Earth-sun relationship on the Solstices/Equinoxes!!

Traditionally, the Solstices mark the beginning of the most treacherous seasons. Being from Miami, when the summer solstice came around everyone always knew that the days would only get hotter. Once the winter solstice hit, we always prayed that there would be some form of respite (news flash, rarely was). Arguably, this is the worst part about living in a city in the south. The distribution of sunlight that causes seasons in most other parts of the world, does not change nearly as much for the equator and the area immediately north and south of it. So while Miami does get more seasons than their Southern neighbors that lie much closer or on the equator, it still experiences intense sunlight during the summer months and still good amounts of sunshine in the winter. 

The Solstices and equinoxes are interesting markers, because while I had always marked them as the gateway to the seasons, I did not realize that they were directly related to Earth’s tilt and its relationship to the Sun. Honestly, I believed that the dates were almost arbitrary, decided based on our calendar by people who just realized that it starts to get really hot in June and really cold in December. Learning that the solstices really mark the day in which the Earth is in the position to receive the most direct sunlight in the Northern Hemisphere (June) and Southern Hemisphere (December), made me ponder why these dates were not the most extreme of the year? Putting this question in the vast context of space easily answers it, as it takes time for the sun’s rays to warm up the earth over all those light years. The order of solstices and equinoxes soon began to click, as I was able to picture the Earth rotating around the sun with differing distributions of light year-round. In spring and fall, we mark the day that both hemispheres swap light distributions from the sun, which then results in the warming/cooling of their regions. However, it did not solve my frustration with my hometown being so hot. Guess I can’t move the earth huh?

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The Universe is HUGE

Posted on January 22, 2024 by sabrinaalperin

Size: Planet vs. Solar System. vs. Galaxy

For as long as I can remember, I have been fascinated by the vastness of the Universe and how everything around us has been untouched by humans. Everyone lives on Earth (unless you are an alien…). Yet, Earth is only one of eight planets in our solar system. Our solar system is centered around the Sun. The Sun is only one of 400 BILLION stars in our galaxy, which we call the Milky Way.

But how large is the Milky Way in actuality? For me to begin to explain the size of objects on a cosmic scale, let me first introduce the concept of the light-year. Despite its misleading name, a light-year is a measure of distance. It refers to the distance which light moves in one year. One light-year is roughly 6 trillion miles. Our Milky Way is huge. It has a diameter of 100,000 light-years, or 600 quadrillion miles! 2.14 x 10^14 continental United Sates could fit in the diameter of the Milky Way. Now imagine: our Milky Way represents merely one of BILLIONS of other galaxies in the universe! That’s crazy!

It is difficult not to be amazed by the incredible size of the universe. Personally, I find the large scale to be exciting. What exists outside of Earth? What can we learn from other planets, stars, and galaxies? However, I am also aware that the size of the universe can also be intimidating. It highlights how small and insignificant humans are on a galactic scale. How do you feel knowing the size of the universe? Does it make you excited or nervous?

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Chapters 1 and 2

Posted on January 22, 2024 by Ayden Harris

Something that I thought was interesting about the readings was the concept of the speed of light, but more specifically how it applies to space travel. We know, based on looking out into the universe, that the universe is about ~14 billion years old. Obviously this means, that if we were to travel at the speed of light it would take us 14 billion years to get to the edge of the universe (assuming the same size universe when we travel). The next star system, Alpha Centauri, is 4.3 light years away. If we convert that to driving at around 60 mph, it would take 48 million years to do it. Because we are much much much slower than the speed of light, it makes me question our ability to be able to travel outside our solar system without the use of wormholes or some other scientific breakthrough that we would need to make.

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The Zodiac and Ascribing Meaning to a Random Existence

Posted on January 22, 2024 by Landon Peaden

Britannica

The twelve Zodiac signs are the most famous (and infamous, if you talk to scientists) way of imposing order and grouping onto our lives. Personality tests, Harry Potter houses (which have to be the laziest version out there), “What sandwich am I?” quizzes, these all apply a person’s traits and responses to fundamental questions about their being to give them their best “match” for whatever category is being used on that particular day.

Generally, these are harmless, joking fun. They are a source of gossip and lighthearted passing of the time, comparing your result to your friend’s and whatnot. But the Zodiac is very real – at least to the followers of astrology.

A quick summary of the Zodiac is that its believers think that the position of the sun and the stars has influence on the events in people’s lives, and that these events will change depending on the Zodiac of the present day, as well as when that person was born. These believers also say that a person’s Zodiac influences their behavior. To be clear, this is a pseudoscience. Astrology is an unfalsifiable theory. Does the position of astronomical objects have an effect on the personality and behavior of humanity? Common sense says no, but even if you wanted to humor the idea, it is impossible to test. Sure, some descriptions of how a Taurus or Gemini behave will match up with people born under those signs, but this is only due to random chance.

And this leads to the bigger point of my thoughts. The Zodiac is simply the most popular and non-religious phenonmenon of trying to apply order, logic, and meaning to what is inherently a random existence. Why do we exist alone in a universe unfathomably massive? The idea that we just happened and that our lives could easily have never formed to begin with is a frightening one. A few random coin flips hundreds of millions of years ago, and the formation of Earth is altered, and perhaps humanity never evolves and we never exist. That we are all stumbling through life on a giant rock that might as well be non-existent on the universal scale with no end goal in sight is sobering.

But if existence is random, then that means life is random in the sense that we are capable of doing what we want – within the constraints of physical, economical, and societal material conditions. There is no set path; no “fate” we are bound to.

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Speed of light in Space

Posted on January 22, 2024 by Andres Becerra

Picture by: FlashMovie/Shutterstock

Light moves pretty fast. It actually moves the FASTEST out of anything that we know of (for now). Light moves at about 300,000 kilometers per second. When I’m in a rush on the freeway, I drive up to 145 kilometers per hour (90 miles per hour) which is only 0.04 kilometers a second. The fastest plane moves at about 12,000 kilometers per hour which is about 3.3 kilometers per second. Light moves a lot faster than that plane and my car.

We also know that things in space are really far away from us. Take our sun for example, it’s about 150 million kilometers away from Earth. The sun emits a light, but even moving at the speed of light, the light takes about 8 minutes to get to us. (You do this calculation by taking 150 million, the distance, and dividing it by 300,000, the speed of light, and that will give you the time it takes in seconds, so to convert to minutes you divide by 60 and that will give you about 8 minutes) So technically, if you look up at the sun (do not recommend without sunglasses) you aren’t seeing how the sun looks right now. You’re seeing how it looked 8 minutes ago. So you’re looking 8 minutes in the past. Let’s take this up another level because 8 minutes is alright. But what if we could look years back in time. Let’s take a look at the star closest to Earth, Proxima Centauri. Even though it’s the closest, it’s still 40,208,000,000,000 kilometers away (40 trillion). So even moving at the speed of light, which we said earlier was way faster than anything we got here on Earth. It takes about 4.25 YEARS for the light on Proxima Centauri to reach us. So if I find Proxima Centauri and I look at it, it doesn’t even look like that anymore. That’s how it looked 4.25 years ago, I’m looking 4.25 years in the past!!

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