Ever stop and ponder the universe?

Think of it this way: Imagine a bacteria in your fingernail that has knowledge about the world, history, and current events. At night, it can look up and observe everything around it. But instead, it’s fixated on what’s happening in your fingernail.

We would find that bacterium quite unimpressive, right? And here you are, often ignoring the magnificence of your surroundings—

Let’s begin by exploring a common subject today: stars.

Stars often come to mind when we think about the universe. They constitute a significant portion of visible matter, and even though most stars are incredibly far from us, we can see thousands with our naked eye at night.

In this post, I delved into the vast array of captivating star facts and selected four that I consider truly mind-blowing—

1) The Observable Universe Contains Countless Stars

Ever gazed at a starry sky in a rural area on a clear night?

In such optimal conditions, you might see up to 2,500 stars. This count represents just a fraction of the stars in our own galaxy.

Consider the Milky Way’s expanse. To grasp its enormity:

– The Milky Way spans 100,000 light years, with a light year equaling the distance light travels in a year—a mind-boggling distance. It would take our fastest spacecraft 18,000 years to cover one light year. The Milky Way consists of about 100 to 400 billion stars.

– Peering at a star on the far side of the galaxy through a telescope allows you to witness how the star appeared 100,000 years ago. Similarly, if someone on the opposite side of the galaxy were observing Earth, they’d see early humans and Neanderthals in action.

– If you envisioned the Milky Way at the scale of Earth, our sun would be barely visible, around 1/50th of a millimeter in diameter.

And remember, the Milky Way is just one galaxy.

In 1995, in a seemingly starless patch of sky, scientists using the Hubble Telescope captured an astonishing image revealing over 10,000 galaxies, each containing approximately 100 billion stars, within a minute portion of space.

The data derived from this image led scientists to estimate that the observable universe hosts over 100 billion galaxies, with a total star count ranging between 10^22 and 10^24, roughly 100 sextillion stars.

Comparatively, a comprehensive study estimated there are around 7.5 quintillion grains of sand on all the world’s beaches, a minute figure when juxtaposed with the staggering volume of stars in the universe—around 10,000 stars for every grain of sand.

Quite the head-spinner.

2) Stars Are Vastly Apart

With the exception of binary star systems, most stars exist in significant isolation across long distances, bereft of immediate neighbors.

Our sun is no exception—the nearest star, Proxima Centauri, lies 4.24 light years away, or roughly 70,000 years by our swiftest spacecraft.

Hence, if the sun were a 4cm ping pong ball in New York, the closest star—a ping pong ball— would be about 1,153km (743mi) distant in Atlanta.

3) Certain Stars Exhibit Incredible Enormity

The grandest stars, known as red hypergiants, boast colossal proportions. One notable example is VY Canis Majoris, towering to a size equivalent to stacking 1,420 suns atop each other. Here’s a visual comparison with the sun:

Illustratively, VY Canis Majoris would be equivalent to a 16-story building in comparison to the ping pong ball-sized sun. It would take an aircraft roughly 1,100 years to encircle it, and if positioned in our Solar System’s center, it would engulf everything up to Saturn’s orbit.

Another mammoth red hypergiant, Betelgeuse, nearly matches VY Canis Majoris in size. Visible as Orion’s upper left shoulder on clear evenings—

4) Some Stars Are Exceptionally Dense and Minute

Following a large star’s supernova demise, a neutron star may form due to gravitational collapse.

Ordinary matter comprises atoms, predominantly empty space with a tiny nucleus at the core. Visualize an atom as a large sphere of 1km diameter— spacious enough to hold two Empire State Buildings. Now, picture the nucleus, like a single pea, resting in the center. The entire atom’s mass is concentrated in the pea.

During neutron star formation, atoms undergo immense compression, causing the empty spaces to collapse and nuclei to merge, creating a sphere densely packed with neutrons. Consider a 1km-diameter sphere now filled with peas—rather than one pea, it contains about 1,000,000,000,000,000 of them.

This phenomenon results in a tiny star roughly 24km in diameter but massing as much as three suns or a million Earths. Below is an illustration of a neutron star, equivalent to cramming 1,000,000 Earths into it:

Neutron stars boast incredible attributes:

– A mere teaspoon of its material matches the mass of 900 Great Pyramids of Giza.

– A neutron star’s density is comparable to squeezing a Boeing 747 aircraft into a tiny grain of sand.

– Some neutron stars rotate at rapid speeds, up to 642 times per second. This means the star’s “equator” travels a greater distance than Earth’s circumference each second.

– Neutron stars radiate intense heat, with interior temperatures ranging from 10^11 to 10^12 Kelvin—over 1,000 times warmer than the sun’s core.

Truly astounding.

Now, back to the fingernail.

Related Blue Jay Blog Posts

How (and Why) SpaceX Will Colonize Mars

The Fermi Paradox

The AI Revolution: The Road to Superintelligence