Robert Jack
Bio
One of the secrets of emotional stability for adults is to keep the expectations of others to a minimum.
Stories (70)
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How scary is Japan's Mount Fuji
Mount Fuji in Japan, is a world-famous scenic spot and is also an active volcano, recently, there is news that Mount Fuji seems to be a bit stupid, which undoubtedly triggered people's concern, then Mount Fuji in the end how scary? If Mount Fuji erupts, how serious are the consequences? Let's talk about this topic below.
By Robert Jack3 years ago in Earth
Why no advanced civilizations have visited Earth
The Earth was born about 4.55 billion years ago, and over a long period, life on Earth has gone through a process from nothing to something, from simple to complex, and finally evolved into humans with higher intelligence.
By Robert Jack3 years ago in Earth
Samsara IV before it became dark
Every shining star in the universe will one day go out, and its "lifespan" is closely related to its mass, the more massive the star, the shorter its "lifespan". For example, the "lifetime" of a Proxima star is about 12.2% of the Sun's mass, and its "lifetime" can be trillions of years, while the Sun's "lifetime" is only about 10 billion years, and the "lifetime" of stars that are much larger than the Sun is even shorter.
By Robert Jack3 years ago in Earth
How empty the universe is
I believe that we all know that the universe we live in is very empty, but if you ask, how empty is the universe? It is estimated that many people have no specific concept the universe is so empty that it is likely to be more than you can imagine. To illustrate how empty the universe is, we might as well start with the Earth and the Moon, where we would normally imagine the Earth-Moon system as follows.
By Robert Jack3 years ago in Earth
Mars is 200 million kilometers from Earth
Among the eight planets in our solar system, Mars is the most popular one, except for the Earth, which is inhabited by humans. Even now, there are still people who believe that Mars may be the second home of human beings in the solar system.
By Robert Jack3 years ago in Earth
"One day in heaven, one year on earth"
"A day in heaven and a year on earth", meaning that a day spent in heaven and a year spent on earth, we generally think that such a situation will only appear in those ancient legends, but in reality, this is not the case, because according to the theory of relativity proposed by Einstein, the passage of time is not constant.
By Robert Jack3 years ago in Earth
A planet of 1 light year
Does a planet with a diameter of 1 light year exist in the universe? One of the more common thoughts on this question is that it is not impossible to form a planet with a diameter of 1 light year if there is enough matter, however, according to the laws of the universe as we know it, such a thing is simply not possible.
By Robert Jack3 years ago in Earth
Between atomic nucleus and electron
Atoms were once thought to be the fundamental particles of everything in the world, but it has since been discovered that atoms are composed of a nucleus and electrons and that there is a vast space between the nucleus and the electrons - how vast is it? Let's take the simplest atom in the universe, the hydrogen atom, as an example.
By Robert Jack3 years ago in Earth
The law of conservation of energy
The spring itself is elastic, after being compressed, the spring will have the tendency to return to its initial state, and therefore has elastic potential energy, which can be seen as the energy stored in the spring as a whole system, so the question arises: if the spring is compressed into a strong acid, then after the spring dissolves, where does the energy of the spring go?
By Robert Jack3 years ago in Earth
Is the sun suspended in the universe?
We often imagine the solar system as if the Sun were at the center of the solar system, not moving, while the eight planets and many other bodies in the solar system are orbiting the Sun in an orderly manner, with the Earth as one of them, which begs the question, is the Sun suspended in the universe?
By Robert Jack3 years ago in Earth
Humans have reached the second level of civilization in the universe
If someone asks, are humans alone in the universe? I believe that most people will give a negative answer. The scientific community also generally believes that in the vast universe, there should be a large number of intelligent civilizations, some of which may even be far ahead of our human civilization, to better describe the level of technology of intelligent civilizations in the universe, scientists also put forward the concept of "cosmic civilization level".
By Robert Jack3 years ago in Earth
Why the Earth is alive and well
According to our knowledge of known life, liquid water is an essential substance for life, in other words, if there is liquid water on a planet, there is a possibility of life, and that is why scientists always consider liquid water as the first condition when assessing the possibility of life on a planet.
By Robert Jack3 years ago in Earth
