Surrounded By The Mechanical Bed We Made

Here's one closer to home. The Kessler Effect is the theory that a single destructive event in Low earth orbit could create a cascade where satellites break up into tiny fragments taking out other satellites, breaking up into smaller fragments and so on, until the earth is completely surrounded by a massive cloud of tiny flying death shrapnel which would make leaving this planet almost impossible.

If you look up how much space debris there is already up there and how many satellites currently orbit, plus the continued growth of the commercial space industry... I think about it a lot.

sosogos

Just A Whole Lot Of Nothing

Super massive voids.

Some as big as 330 million light-years in diameter. 330 million light years of almost nothing, no stars, no galaxies, no planets.

Frustratid

A Little Farther Every Day

People think that the universe is expanding and more stuff is added but that's not the case.

New stuff isn't being added, the universe is just being stretched out slowly. Every minute that passes space travel becomes a fraction less likely. And in a google, the universe will have stretched so thin that there is nothing left

bebasw

Lurking Out In The Inky Dark

The dark forest theory as a answer to the Fermi paradox.

If i remember correctly it's from a sf book trilogy,

https://en.wikipedia.org/wiki/The_Dark_Forest

It's the idea that we don't see signs of civilizations in space because all civilizations that revealed themselves on a astronomical level got destroyed by other malvolent aliens lurking silently.

Then you remember the voyager probes and all thoses signals we send to space!

wanroww

Every Time You Think About Lightyears Your Brain Dies A Little

Lightyears.

The fact that I can't move as fast as light. Even if I could, I wouldn't live long enough to last the journey.

Such a tease.

internet_humor

Galactic Bumper Cars

The fact that the galaxy closest to ours, Andromeda, is heading our direction at a speed of about 200 miles per second, and one day the two will collide, possibly launching our solar system into deep space in the process.

270astro

Ha-Ha-HaYeahbuwhat?

MOBILE

BLACK HOLES

Blubari

To put it in perspective it's exactly the kind of thing we'll never know about.

Because if there was one heading straight toward us, we would be so uneqivacoly f-cked the absolute best-case scenario is to just engage in global information suppression and murder anyone who finds out so that the rest of the population don't descend into whatever chaos realizing we're all going to die and there's nothing that can be done to stop it, would occur.

I think the only thing we could do is literally move the planet and/or solar system out of it's way.

That's the most realistic thing we could do.

The Ultimate Influencer

The Great Attractor.

A... thing... that affects the motion of galaxies for hundreds of millions of light years.

Sabz5150

It Could Be Anything. It Could Even Be A Boat.

The Bootes void.

An area of space where there should be 50,000 or so galaxies (compared to other areas of the same size) but there's only about 60. Could just be empty space for some unknown reason, or it could be an ever expanding intergalactic empire using Dyson spheres. Also I think it appears to be growing but that could just be galaxies moving away from the void

Edit: so it turns out it's 2000 and obviously it's not gonna be aliens but the theory is still cool af

Nazi_Marxist

We Might Already Be Gone

Vacuum decay is one of the scariest concepts to me. We don't know if it exists, and we won't know until it's too late.

Marycate11

On the other hand, you'll never know. You'll just blink out of existence one day. So nothing to worry about.

Tom_Brokaw_is_a_Punk

Perfection Or Coincidence?

Total Solar Eclipse and its existence.

Explanation:

It sheer coincidence and perfect match.

Coincidence: The size of Moon and Sun as perceived from Earth is exactly the same. So then moon gets in between Earth and Sun, it almost completely covers the Sun. There is no scientific reason that they should appear to be of the same size from here. Infact, we have not found this phenomenon anywhere else till now. Fun Fact, in next 600 million years, the moon would have drifted so far apart that we will not be able to see any total solar eclipse after that. We are lucky to have borne in that small window of time to witness it.

Perfect: The size match between Sun and Moon is amazingly perfect. It is neither too much, nor too little. Infact, the match is so perfect, that astronomers used total solar eclipse to watch and study Sun's Corona, the sun's atmosphere (consisting of mostly hot ionised gases called plasma) which remained uncovered by the Moon's shadow.

The amazing level of coincidence and perfect match makes me wonder 'at times' of an intelligent design.

greymatterrules

What Can Stop A Nebula?

The coldest thing to ever exist is half a kelvin degrees. Thats near zero. Half a kelvin is almost -274.15 degrees C which is absolute 0. Mothing can move and nothing can happen.

This thing that is almost [impossible] to move? A F-CKING NEBULA. I find it [terrifying] that a nebula formed from a star (fact check me if I'm wrong of course, I'm not an encyclopedia) which is MILLIONS of degrees, could be cooled down to almost absolute zero.

Memesandstupidity

Let's Do Some Math! For Fun!

Its vastness.

If you become a 100 years old, that's 100*365*24*5 = 4380000 or 4.4 million kilometers that you could walk, if you walked 5 km/h, every day, all day.

Now here's the kicker:

Mars is 141 million kilometers away from us. We can barely walk 3.1% of the way.

If we ran 25km/h, every day all day, we would be 15.5% of the way.

We wouldn't even be able to go to the nearest f-cking planet.

Even walking to the moon would take us 8.77 years. Running? Just a measly 1.75 years

Even taking the car with 100km/h (62 miles/h) would take us at least 160 days to the moon, assuming no breaks, of course.

NostraDavid

Think Billiards, But In Space

Rogue planets: Planets that do not follow any given orbit.

They may have been in an orbit at one time, but now they refuse to "play by the rules."

They were most likely knocked out of their orbit by another body, and now they are set on doing the same.

Ha-Ha-Ha-HaThat Was So Close...

Astronomer here! There are a lot of things posted here that are not really likely to happen any time soon or affect your life on Earth much. So, if you want something to worry about, may I introduce you to the Carrington Event of 1859. Basically Carrington was a scientist who noticed a flash from a huge cluster of sunspots, which was the biggest coronal mass ejection from the sun ever recorded (aka a ton of material ejected from the sun at high speeds). It hit Earth within a day- aurora were seen as far south as Hawaii, wires on telephone poles burst into flame, and telegraph operators even reported contacting each other when not connected.

If a similar event were to strike Earth today, it would cause billions of dollars in damage, because blown transformers are super hard to replace and a lot of satellites wouldn't be able to handle it (and it goes without saying you'd have a serious radio blackout for a bit until it ended on a ton of essential frequencies).

The crazy thing about the Carrington event though is we really have no idea how often such events happen. But we do know that in 2012 there was a Carrington-level solar flare that barely missed Earth...

Andromeda321

We're Just So, So, So Small...

This visual that either shows how slow light speed is or how vast space is, depending on which way you look at it.

I've seen videos showing the scale of the universe before, but this one really hit home for some reason. The speed of light, the fastest speed possible, looks painfully slow when you look at it in the context of even a fraction of our solar system. We're stuck here, aren't we?

Digibollocks

SERIOUSLY. Bigger Than We Could Possibly Imagine

The sheer distance between things. It's scary and somewhat depressing.

Regretful_Bastard

It often blows my mind when I look up at 2 stars that look super close together and realise they are probably just as far apart from each other as they are to us.

kaiserpuss

When you look up at the night sky (in any urban areas or those with sufficient light pollution...) The stars you see (think the constellations and other bright stars) with the exception of the super bright blue A-Type stars, they are usually no further than 500 light years away.

The biggest, brightest (non A-Type) star in our typical (night) sky is also one of the biggest discovered in our galaxy: Betelgeuse. At 541 light years from earth is it the furthest star in the Orion Constellation.

Those A-types I mentioned, can be seen to about 2000 light years away.

Our galaxy is between 70,000 (main core of stars and the limbs) and 150,000 (the outliers before you get to the clouds (other galactic remnants from old collisions) ) light years across.

Only seeing those stars that are 500 light years in radius gives us less than 1% of our galaxy to light up our night.

Space...

Space is unimaginably huge.

Acysbib

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