Cool Astrophysics
"Pick a flower on Earth and you move the farthest star."
- Paul Dirac
The Big Bang
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S ir Edwin P. Hubble (1889-1953) was an astronomer. In the 1920s he proved that the distant cloudy objects in the night sky were actually other Galaxies, some much like our own Milky Way Galaxy. Each one contains Billions of individual stars. In 1929 he calculated the distances to thousands of Galaxies and also their relative speeds towards or away from us. He observed that the further away a Galaxy is, the faster it is moving away from us. This is now referred to as Hubble's Law. The Law makes use of an Expansion Factor known as Hubble's Constant Ho. Current technology has been able to measure the Recession Speeds of over 930,000 Galaxies! What does it all mean? The entire universe seems to be expanding and getting larger each day!

Hubble's Law:   Vr = Ho x D     (Velocity of Recession = Hubble's Constant x Distance)

H ubble's Law has enormous implications. If everything is expanding then that means yesterday things were a bit closer; the week before even closer; a million years ago very much closer. By running the clock backwards, it is our best approximation that our universe began from a Singularity approximately 13.7 Billion Years ago. This event has been the moniker, "The Big Bang".   We have simply opened our eyes to the heavens.

Ho (Hubble's Constant) = 73.8 km/sec/Mpc   (Mpc = Mega parsec = 3.26 million lightyears)   Parsec ≈ 3.26 ly

B etween September 24, 2003 and January 16, 2004 the Hubble Space Telescope photographed one tiny 'blank' spot in the sky - a ½ mm circle at arm's length! The total exposure time was 11 days 8 hours. It revealed over 10,000 galaxies, each one containing billions of stars.

🌌 View the Hubble Ultra Deep Field Photograph
📏 Scale Invariance of Empty Space 📏
On November 10, 2017 André Maeder of the Université de Genève published a landmark article for the American Astronomical Society that explained away two theories, those of Dark Matter & Dark Energy. These concepts have remained unproven by science for 80 and 20 years, respectively. Maeder suggested both could be explained away using the concept of Scale Invariance of Empty Space.

The Scale Invariance of Empty Space is similar to the concept of Fractal Geometry and allows us to describe the Large Scale Structure of the Universe. It means that there can be a relativlely simple mathematic description of how something grows or expands (plants, people, lightning bolts, and even the entire known universe). This 'code' can be iterated ad infinitum to create infinite complex geometries.

T he use of Fractals by the way, made possible the ability of cell phones to receive and transmit billions of different frequencies without using enormous antennas. Every cell phone now uses a 'Fractal Antenna'.

Dark Matter  was an idea first put forth in 1933 by the Swiss Astronomer, Fritz Zwicky to describe the observed, faster than predicted, rotational speeds of distant galaxies. The 'explanation' solved the problem but in 80 years no one had ever detected this 'Dark Matter'.

Dark Energy  was a concept put forth in 1998 to describe the observed exponential acceleration of the universe. Einstein was ahead of the rest when he introduced his Cosmological Constant that addressed this phenomenon. He later abandoned it but recognized he should have retained it in his equations. We don't have a clue what Dark Energy is but it makes all the equations work.
Voyager Spacecraft
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T he Voyager 1 & 2 Interstellar Spacecraft that we launched in 1977, each had a Gold Record onboard announcing our species to the cosmos. Currently these spacecraft are moving at 40,000 mph through interstellar space. On September 5, 2017 after 40 years in space NASA-JPL 'beamed' a message to Voyager 1 to be included in it's memory. The message was chosen from over 30,000 submitted suggestions. The message had a 60 character limit and took over 19 hours to reach the spacecraft. The following message was chosen and beamed to Voyager on the order of none other than William Shatner (Captain Kirk of Star Trek).

"We offer friendship across the stars. You are not alone."
🛰 Voyager 1 & 2 ~ NASA's JPL Page ~ Current Speeds, Distances, Cosmic Ray Data, etc.

🛰 Voyager 1 Fires Its Thrusters In Interstellar Space After 37 Years !

V oyager has 3 linked computers onboard with a total capacity to store only a few thousand words and process them at 8K/sec. By comparison, your iPhone can store over 100 Billion words and process them at 14 Billion/sec. That is 1.5 MILLION TIMES FASTER. Today, just 40 years after their launches, we have the technology to send the entire knowledge of humanity in a memory device the size of a pea! If we wanted, we could broadcast thousands of these out to the stars in every direction and at significant percentages of the speed of light. Perhaps other civilizations have already done this? Perhaps knowledge could be transferred on a single beam of light itself? There are so many possibilities. We must be open to all.
The Interstellar Object  'Oumuamua'
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I n 2017 the First Verified Interstellar Object passed through our inner solar system following a fast well defined hyperbolic trajectory. It passed through the solar system inside the orbit of Mercury and came within 20 million miles of Earth. We did not notice it until 40 days AFTER it had already passed us. Whoa! It was named, 'Oumuamua which, roughly, is Hawaiian for fast traveler. It is noteworthy because its speed greatly exceeded the natural gravitational speed that was expected. Many theorists suggested it could even have been deliberately sent by another extraterrestrial species. It was given a new class designation (I) for Interstellar, I|/2017 U1

I t is also noteworthy because as it left the inner solar system it accelerated faster than expected, but this may have been due to an assist from the Solar Wind. Also, unlike naturally occurring comets and asteroids, it had no trail streaming out from it.

'O umuamua is dark red and has an elongated cigar shape nearly a kilometer long by 100 meters across. As it raced by us at nearly 200,000 mph it was tumbling erratically through space.

☄️ 'Oumuamua (Article and Video)
The Fermi Paradox
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(quietly) Where is everybody?
W e might be advised to reign in our egos concerning interstellar contact. Until it's Proven that we are the toughest, badest guys on the block, it would be prudent to keep a low profile. Evolution has proven the best approach to survival is to lay low and keep quiet. Stealth ≡ Survival. How arrogant are we? In my opinion, any civilzation capable of Interstellar Travel, would consider us as trivial as the ants that we plow under in our corn fields. However, they might like our planet, and therein lies the REAL danger. Better to stay quiet and keep the Earth for ourselves. We know Earth is a brilliant blue marble in the cold black depths of the cosmos. Indeed, perhaps extraterrestrial civilizations are purposefully keeping quiet in order to protect themselves from what's out there. The lack of contact with any ETs is known as The Fermi Paradox, from Enrico Fermi (1901-1954), and makes use of the Drake Equation.

P erhaps it is because earth has an infestation of people that no one is interested. We may be viewed as so abhorrent to extraterrestrials that they prefer to avoid us at all cost. Sure we have learned to fly and reach into space, but we are also suffocating in our own excrement. Consider the plastic refuse patch float in the Pacific Ocean that is now twice the size of Texas! How would we approach another planet similar to earth? Too dangerous maybe?

A re all civilizations capable of space travel doomed to perish in their own global warming catastrophe?
Or perhaps at the hand of runaway A.I.?
One estimate for L in the Drake Equation is a mere 200 years!

👽 The Fermi Paradox ~ Too Dangerous To Communicate?

📡 Charles Krauthammer ~ Are We Alone in the Universe?

💥 The Great Filter ~ Interstellar Travel is Just Impossible

😵 Potential Risks to Earth and All Its Life

T he GREAT FILTER hypothesis sugests that there is an Existential Point for all Advanced Intelligent Life that prevents that life from further advancement or terminates its existence! Possible types of filters would be the following Extinction Level Events, but what is more troubling are those that we cannot imagine!
  • Nuclear War
  • Nanotechnology
  • Artificial Super Intelligence
  • Asteroid or Comet Impact
  • Collision with another Star
  • Stellar Gamma-Ray Burst
  • Super Pathogen
The Drake Equation
🤔 The Drake Equation (1961) aka A Fermi Problem Solution

N = R* · ƒp · ne · ƒl · ƒi · ƒc · L

N, the number of active, communicative extraterrestrial civilizations in our galaxy
R*, the average rate of star formations, in our galaxy
ƒp, the fraction of formed stars that have planets
ne, the average number of planets that can potentially support life
ƒl, the fraction of those planets that actually develop life
ƒi, the fraction of planets bearing life on which intelligent, civilized life, has developed
ƒc, the fraction of these civilizations that can broadcast into space
L, the length of time over which such civilizations broadcast signals
Interstellar Travel
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L et's step back a moment. Let's take a breather and sit down in a comfortable chair; perhaps enjoy a nice hot cup of our favorite Tea or some hot chocolate and put our legs up. Let's put ourselves in an academic and reflective frame of mind. Now then, let's think about the REAL possibility of travel to other stars and their habitable planets. What are the problems?

T he overwhelming problem is DISTANCE. The stars are so very far away! The closest star known to have a possible earth-like planet is Alpha Centauri, which is 4.37 LIGHT YEARS away. That is such an enormous distance. Our fastest rockets capable of carrying people can barely reach a speed of 25,000 mph. Unmanned Voyager is the fastest ship we have and is currently moving at 40,000 mph. Let's for a second consider our rocket and slingshot maneuvers might somehow be able to reach the fantastic speed of 100,000 mph.
I will do the math for us…

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S o, even with our rocket's great speed it would take us over 29,000 Years, to reach the nearest star! That is a real number, not tied to any faster-than-light science fiction but rather tied to real concrete facts. How can we possibly survive the journey? The short answer is: we can't. By no stretch of the imagination could we develop some kind of suspended animation device that could enable us to sleep for that long a time. It simply isn't possible. And by a similar logic, I believe it would NOT be possible for extraterrestrial beings (ETs) to visit us - the distances are just too great. Corporeal life is too delicate.

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O ne solution to this dilemma is to consider the use of Artificial Intelligence to perform the task. Perhaps after we reach our Technological Singularity here on Earth, an A.I. could upload all of your brain patterns and essentially BECOME you, with the great exception that the new A.I. 'YOU' could power-down and 'sleep' (if it wanted) for an enormously long time and not decay. Then A.I. 'YOU' could travel to the nearest star and beyond. Time would NOT be an obstacle for an A.I. This new 'YOU' would essentially become immortal, and forever is a very long time.

C onsidering the enormity of all space and time, there must have been many extraterrestrial civilizations that have ALREADY reached their own Technological Singularity and have possibly launched A.I. explorers into the cosmos. Consider that A.I. ships can be nano-sized ships (1 billionth of a meter), and on that scale they can be accelerated to near the speed of light relatively easily. So the SHIPS themselves are the A.I. To me, this is more acceptable than imagining organic, corporeal life traveling through the immense vastness of outer space. There could have been many such A.I. visitors to Earth in the past. Humans have existed on Earth for 3 million years, modern humans for 200,000 years, and space going technology for only 60 years — not even an eyeblink in time! What would ETs have thought of us? Were we amusing, slightly advanced apes, mucking about on the surface of our beautiful little world? Probably.

A lternatly, perhaps it is the destiny of every civilization everywhere to evolve out of the primitive, explore science, create art, and enable an intelligence sigularity which creates A.I. and then perish because of it. If that is so, we would never hear from anyone, would we?

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A n unsettling thought is to imagine the Earth as a Prison Planet, drifting along out here, in the sparsely populated, Orion Arm of the Milky Way Galaxy. Perhaps ETs abandoned their worst here and then left, knowing that the inmates would never be able to escape to reach other stars - a perfect prison, much like Botany Bay in Australia. That would make us either descendents of ETs or from the Earth creatures that were somehow changed by their presence.

L et us finish our Tea (or chocolate) while we ponder these possibilities and more. At least there is Tea.

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Solar System Scale Model
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O ur solar system is big — REALLY BIG. It's easier to appreciate its size if we imagine a large scale model. Only 24 humans in all of the billions who have ever lived that have seen the EARTH as a ball. They left earth orbit and traveled to our MOON and along the way they looked back to view the entire planet. James Irwin of Apollo 15 compared the EARTH to a Beautiful Blue Marble floating in space. Let's make THAT our reference unit then. The EARTH will be the size of a Marble, 0.6 inches in diameter. At that scale our own MOON will be .19 inches in diameter and 19 inches away from us.
🔭 A Scale Model Solar System in the Nevada Desert

O n our Blue Marble Scale our SUN will be a nuclear fireball over 5 feet in diameter. Many Native American cultures consider the Stars to be "Campfires in the Sky" with other, unseen, tribes huddling around them. Not far off the mark, I think. I really like that analogy and, for our model, it will work quite well. Let's imagine a 5 foot diameter really hot Campfire with flames reaching up into the night sky. The closest planet to this five foot Campfire is MERCURY, which on this scale is a tiny ball-bearing only one quarter of an inch in diameter, and it is about 225 feet away! Even at that distance from our nuclear Campfire, lead will melt on MERCURY's surface!

T he next two planets out are VENUS and EARTH. VENUS is about the same size as Earth, but it is shrouded in clouds so let's represent it as a small White Marble. VENUS is 420 feet away from the SUN. And on this scale our little Blue Marble EARTH is 600 feet away (two football fields!). Even at this distance the nuclear Campfire throws out enough energy to power all life on our World and burn unprotected skin in a matter of hours. MARS is next. MARS is a small red pebble only one-third of an inch in diameter and orbits our SUN-Campfire at a distance of almost 900 feet. So, within this huge eithteen hundred foot sphere of nothingness, are only FOUR-TINY-BALLS and a few even smaller Moons, that would collectively ALL fit inside a teaspoon!

N ow come the big planets, but they are MUCH further out from our 5 foot SUN-Campfire. JUPITER, the biggest planet in our solar system, would be a small ball 7 inches in diameter. It is an amazing 3,000 feet (.57 mile) away from our SUN-Campfire. Next, SATURN, the beautiful ringed planet, would be a 5½ inch ball, with paper-thin rings, at a distance of over 1 mile!

T he 'Outer' planets are next. URANUS is a Tennis-Ball-Sized world and orbits over 2 miles out. Next we have NEPTUNE, also a Tennis-Ball-Sized Blue world orbiting a full 3⅓ miles out from our SUN. That is a long way away from our Campfire. Lastly, we have the planet PLUTO, which is a very tiny world. It is the size of a ball-bearing only an eigth of an inch in diameter and it is about 4½ miles away from our SUN-Campfire! So, inside this gigantic 9 mile sphere are 9 little worlds, including our own Blue Marble World, EARTH. We had better take care of it. It is a very, very long way to the next Campfire in the Sky.

OUR CLOSEST STAR NEIGHBOR
In this Blue Marble Scale the closest other Campfire in the Sky in any ANY direction is Alpha Proxima, which is over 30,000 miles away from our humble 5 foot diameter Campfire. That is a LOT of empty space.

🌌 NASA's Planetary Fact Sheet (Detailed Planet Data)