i thought that you would be interested in this :
https://youtu.be/0jHsq36_NTU
https://youtu.be/C4V-ooITrws
( not sure if this is accurate, but nice nonetheless! )
Love anything and everything about space. When you read things like our solar system is travelling through the universe at 70,000 miles per hour then it really shows just how big space actually is. It's scary when you think about it.
well, this "helical" model is probably more fantasy than accurate, since with the "elipse" model, they have apparently managed to reach their targets and take photos of planets like they predicted. (nothing that i can verify myself, the only things i can see is the sun, the moon, the stars, and sometimes a shining dot of another color (like Mars, a red shining dot, this summer in the sky))
anyway, since Krischan has made similar demos about our solar system, i thought that he would be interested in these graphics / animations...
Oh, one of my favorite subjects. ;D
I know this video but the theory behind is implausible IMHO. But did you know that our solar system is not aligned exactly at 90° to the galactic plane but is rather inclined "obliquely"? The first attached image is how it looks from the direction of the galactic center (the attached picture is from here (http://calgary.rasc.ca/howfast.htm), an interesting page). You can see it in the Space Simulator (http://spaceengine.org), too, which simulates the inclination correct. And we are moving around the galactic center, but as far as I have understood that we are not really moving away from it, the solar system is moving only up and down through the galactic plane. And the speed is INCREDIBLE fast. Think about this:
Let's start with how fast the earth spins
The earth has a circumference of 40,075 kilometres at the equator. At the equator, the earth has a circumference of 40,075 kilometres. This means that you permanently move with a speed of almost 1670 km/h from west to east. That's one and a half times the speed of sound! Don't you notice? Because everything around you on Earth is moving as fast as you, you will not notice a thing.
But the rotation speed of the earth is nothing compared to how fast the earth orbits around the sun. In a mean distance of almost 150 million kilometres, we circle around the sun once within a year. That makes a cruising speed of 107.280 km/h. This is faster than the NASA probe New Horizons which explored Pluto.
But let's go on. The earth orbits with the solar system the center of the Milky Way. At an incredible speed of 900,000 km/h! And our home galaxy is traveling at 1,987,000 km/h, relatively seen to the cosmic background radiation. In comparison to the speed of light (1.079.252.848,8 km/h), however, this is still slow.
Why do we don't notice this? Well, that's because, as Einstein said, everything is relative. We are like a fly flying around in a moving car. She doesn't notice anything - and neither we do. This is great, isn't it?
But there is more to know. For the historical movement of the sun I have another small excursion for you. The sun did not originate where it is today and most of the neighbouring stars are only our neighbours, but not our siblings (scientists can derive that information from their observations and calculations today).
- at the beginning the sun was in a star formation area (cluster)
- this star cluster must have had at least 2,000 stars and a maximum of 100,000 stars
- at the time of formation there must have been 10,000-100,000 stars in their immediate vicinity
- and there were a lot of "fly-bys" of other young stars
- the sun must then have been about 1 light year away from a supernova explosion
- the exploded star had about 25 solar masses, so it was quite big
- this is how most of the planets of our solar system known today (and also us) came into being
- the cluster then dissolves over time and the stars "went their own ways".
- due to the increasing distance to other stars the planetary orbits remained stable until today
The stars of the birth cluster of the Sun have been widely distributed over the last 4 billion years and today we are in a region of the Milky Way that differs significantly from the environment of the Sun at the time of its formation. As far as I know, the origin of the sun has not been clearly identified until today, for a while it was thought that it was born in the star cluster M67, but has now been refuted.
In this document (https://arxiv.org/pdf/1405.1723v1.pdf) there is a list of candidates whose composition is very similar to that of the sun, i.e. they seem to come from the same star forge, the so-called "Solar Sibling Candidates", siblings of the sun. However, many of them are smaller M dwarves. But the next time you look up to Vega, there is the star HD 162826 (https://en.wikipedia.org/wiki/HD_162826) - an old friend of the Sun. ;)
Our current situation is like that: our solar system is currently "embedded" in the Local Bubble (https://en.wikipedia.org/wiki/Local_Bubble) - an area of relatively low density interstellar matter measuring about 300 light years in diameter. At first it was thought that a supernova explosion and the formation of the pulsar "Geminga" had to do with it. Meanwhile it is assumed that a whole series of supernovae (14-20) in the last 15 million years are responsible for this.
Inside this local bubble, the solar system is currently ("currently is a cosmic wink, which still about 70,000 years!) crossing an area called the "local flake". This is an area where in a cube of ten centimeters edge length there are only 100 atoms - interstellar clouds are usually 100 times as dense. The local flake is about 7,000 degrees Kelvin hot and the local bubble even up to 1,000,000 Kelvin! There are studies on the subject that we could cross such a hot region in 100 years from now. The temperatures sound spectacular, but the specific heat capacity of the medium has to do with the density, so we - respectively our descendants - won't notice that.
So much for that. Sorry that I had to be brief :o And: "The fact that we live at the bottom of a deep gravity well, on the surface of a gas covered planet going around a nuclear fireball 90 million miles away and think this to be normal is obviously some indication of how skewed our perspective tends to be." (Douglas Adams) So don't panic! :P
Great post, Krischan. Cool stuff.
Quote- at the beginning the sun was in a star formation area (cluster)
- this star cluster must have had at least 2,000 stars and a maximum of 100,000 stars
- at the time of formation there must have been 10,000-100,000 stars in their immediate vicinity
- and there were a lot of "fly-bys" of other young stars
- the sun must then have been about 1 light year away from a supernova explosion
- the exploded star had about 25 solar masses, so it was quite big
- this is how most of the planets of our solar system known today (and also us) came into being
- the cluster then dissolves over time and the stars "went their own ways".
- due to the increasing distance to other stars the planetary orbits remained stable until today
I don't believe it. no to the 'must have been in a big star cluster' theory. The sun may have been in a system of a small few other stars, but also possible it was a loner right from birth.
No to the ' sun must have been about 1 light year from a supernova ' theory, and its mass estimate and its assertion that Sol's planets required this event. Planets commonly form round most if not all star systems.
Old theories from the middle of the 20th century need updating in light of recent discoverys, one of them being that exo-planets are abundant.
If you believe it or not - well, science is not a religion. Science is a method that was specially developed to get objective insights about our world, but which you don't have to believe. These are the results of observations, falsification and conclusion. The article is in german only but the study is in english. And this is not "an old" theory, it is from 2012.
https://www.mpifr-bonn.mpg.de/3018651/2013_1 (https://www.mpifr-bonn.mpg.de/3018651/2013_1)
https://www.aanda.org/articles/aa/abs/2013/01/aa18792-12/aa18792-12.html (https://www.aanda.org/articles/aa/abs/2013/01/aa18792-12/aa18792-12.html)
https://www.aanda.org/articles/aa/pdf/2013/01/aa18792-12.pdf (https://www.aanda.org/articles/aa/pdf/2013/01/aa18792-12.pdf)
But in the end everything we know about the universe is only the result of observations and calculations and the realization that the physical laws we have found out so far are not only valid for us on earth but everywhere and can make predictions without ever having been there ourselves. In principle only electromagnetic waves and movements of solid bodies are observed and the rest is mathematically calculated and statistically modeled, we can't do more from Earth. And think about what we have already found out from this alone: heliocentric model, Kepler's laws, Newton's laws, there is more than just one galaxy, theory of relativity, big bang, extrasolar planets, etc...
Science, in contrast to religions, constantly corrects itself. So one scientist researches something new, collects data, then creates a hypothesis based on the scientific method (keyword: falsification, standards) and then makes it available to everyone who can test it himself. And every other scientist who would like to do so tests it with the aim of finding a mistake in the hypothesis, but not out of malice but for the sake of objective truth. And if nobody finds a mistake, the theory is the current "state of knowledge", not the "truth". And if they find a single mistake, another theory is needed to match the observations and data.
As far as I know, it has not been falsificated until today but I'm not a scientist - I'm just interested in this subject. So, "believe" is the wrong word regarding science. If there is a newer theory I'd like to know about it.
Science is done in-situ, using theories and measurements to predict the future, usually with full relevant knowledge of the object being studied.
In contrast observational cosmology is done at distance, its theories are often about history rather than the future, and most of the relevant details of the object are guessed rather than known.
It's a beginner error to confound them.
Observational cosmology has nowhere near the reliability of science and its theories are so routinely falsified by new space data that its considered normal and not newsworthy. Compare that to hypothetically breaking the laws of physics, it would be shock news considered impossible.