Solar System vs. Galaxy vs. Universe!

[fuzzems]

Solar System vs. Galaxy vs. Universe!


Here are some definitions from a dictionary:



Solar System: Consists of the Sun, and everything bound to it by gravity. This includes the 8 planets and their moons, the asteroids, the dwarf planets, all the Kuiper belt objects, the meteoroids, comets and interplanetary dust.



Galaxy: large system of stars held together by mutual gravitation and isolated from similar systems by vast regions of space. The Milky Way measures about 100,000 light-years across, and is thought to contain 200 billion stars.



Universe: the totality of known or supposed objects and phenomena throughout space; the cosmos; macrocosm.



So to sum it up:



We live on planet Earth which is part of our local Solar System.

Our Solar System includes the Sun and everything that orbits the Sun.

Our Sun, is just one Star in the Milky Way Galaxy.

The Milky Way Galaxy is just one Galaxy in the Universe.



www.learningastronomy.com/solarsystem_galaxy_universe.html

[fuzzems]

The Milky Way’s 100 Billion Planets

A six-year search that surveyed millions of stars using the microlensing technique concluded that planets around stars are the rule rather than the exception. The average number of planets per star is greater than one. This means that there is likely to be a minimum of 1,500 planets within just 50 light-years of Earth.
The study concludes that there are far more Earth-sized planets than bloated Jupiter-sized worlds. This is based on calibrating a planetary mass function that shows the number of planets increases for lower mass worlds. A rough estimate from this survey would point to the existence of more than 10 billion terrestrial planets across our galaxy.

www.nasa.gov/image-article/milky-ways-100-billion-planets/

[fuzzems]

Astronomers have discovered 5,502 planets around other stars (known as exoplanets) in the Milky Way. Add in the eight in our solar system (not nine, sorry Pluto), and that gives us a total of 5,510 known planets, all located in our own galaxy. Counting planets is a hard task, though, and astronomers are certain there are many more out there we haven't found yet.

"Even though we only know of around 5,000 planets right now, we can estimate that there is roughly one planet for every star," Mark Popinchalk, an astronomer at New York City's American Museum of Natural History, told Live Science."Our galaxy has 100 billion stars, and so likely has around that many planets. We can't give an exact number."

www.livescience.com/space/how-many-planets-are-in-the-universe#:~:text=Astronomers%20have%20discovered%205%2C502%20planets,located%20in%20our%20own%20galaxy.

[fuzzems]

Data from planet-hunting telescopes, such as the Kepler telescope, suggest that on average, every star is orbited by at least one planet. Since the Milky Way has an estimated 100-billion stars, that translates to 100-billion planets. However, it is important to note that this average is based on only a few thousand stars, and when the galaxy contains many billions, the true average number of planets could be significantly different.
Our solar system contains one star and eight planets. The number of planets in our solar system significantly outnumbers the number of stars. If every solar system contained more planets than stars, then the number of planets in our galaxy would vastly outnumber the stars. The estimate of 100-billion planets is likely the least possible number of planets. If every star is orbited by the same number of planets in our solar system, then there would be 800-billion planets, or eight times the number of planets than stars. Even if every star were orbited by only two planets, the number of planets would still be twice as high as the number of stars.
www.worldatlas.com/space/how-many-planets-are-in-the-milky-way.html

[fuzzems]

This is mind boggling. I mean you think of the earth and sun and the planets in our solar system as if somehow that is the sum total. But never thought that much that there were billions of planets just within the milky way.

[sauerkraut]

I'm a big Astronomy fan that stuff really interests me. Those "Bloated Jupiter's, sometimes called hot Jupiter's" are a fascination in themselves, some orbit so close to the star closer in then our Mercury is that they are phase locked to the star and thus show only one side to the sun the other side is in perm. darkness which results in massive high speed winds whipping 'round the planet some say the wind speeds are as high as 6,000 kilometers/hour.

[sauerkraut]

There are billions of suns in one galaxy so if just one of those suns has an earth-like planet, and with the billions of galaxy's out there there must be tons of other Earth like planets. Something else that is interesting people don't realize how big our Solar System is and the vast distances between planets, Jupiter is way out there around 778 million km from the sun (about 470 million miles) and Saturn is twice that distance from the sun and Uranus & Neptune double that distance. The Voyager space probe has been traveling since 1977 as mans fastest object at about 40,000 mph and as of November, 2023 has gone 24 billion km, or 162AU mans most distant object and it just recently reached the edge of the suns influence, the suns terminal shock wave as they say- then there is the Kepler belt & the Oort cloud is even farther out Voyager won't hit that for another few thousand years at it's current speed.

[sauerkraut]

What's interesting to think about is of all the planets in our solar system none are alike, each one is totally different than the others, even 'twins' like Uranus & Neptune are totally different, Uranus is orbing on it's side tilted at 98 degrees, Neptune has more internal heat than Uranus and has the highest winds in solar system along with a moon that orbits the wrong way. Even the 'twins' like Venus & Earth are totally different in more ways then one,(Venus is sometimes called Earths sister planet) Venus rotates very slowly and in retrograde, so the sun rises on Venus in the west & sets in the east -that is if ya could see the sun thru the Venus clouds.
Even the moons in our solar system are all different from one another - the 4 Galilean moons of Jupiter are totally different from one another.

[sauerkraut]

What would be interesting to think about is life on a "Super Earth" a planet that is likely to be orbiting 'round another star, that would be an Earth-like planet that is about the size of our Neptune only as a solid rocky planet -not a gas ball as our Neptune is- gravity would be much higher there and distances would be greater, flying would use more fuel due to the higher gravity, mountain ranges would be smaller due to the high gravity- an Earth with a diameter of 24,000 kilometers or about 15,000 miles, Early travel would be harder, slower & longer, oceans would be larger to cross. There would be alot more real-estate to nations to conqueror in wars that's for sure.

There could also be more different races or cultures of people on such a large planet Earth since everyone and early cities would be spread so far apart.