At night when you look at the star sky, what do you often think about? Are we really alone in this universe? Ultimately, where is the frontier of the universe?
The truth is that the vast space outside our planet contains many secrets that science cannot yet know. But in contrast, there are also some interesting surprises that after thousands of years of astronomical research, people have used their intelligence to observe, infer and conclude.
What are the most unexpected things you can tell yourself when you look up into the night sky?
1. Why the neutron can spin at 600 rpm
When a star reaches the neutron star stage, it has reached one of the last points of the evolutionary journey. These massive stars were born during supernova explosions, but they collapsed themselves into their cores by a radial gravitational force, which then rotated extremely fast as a physical consequence. of that process.
Normally, neutron stars can spin up to 60 revolutions per second after being born. But in a special case, this speed can be increased to more than 600 rpm.
2. The universe is completely still
In order for sound waves to reach your ears and bounce off your eardrum, it needs an environment to spread. But because there was no air in the vacuum of space, there was always a strange, strange silence.
In contrast, on Earth there is atmosphere and air pressure that allows sound to travel. That explains why there is so much noise on the ground.
3. The number of stars in the universe is an uncountable number
Basically, we don’t know exactly how many stars are in the universe. But scientists can use estimates to answer the question: How many stars are in our galaxy, the Milky Way? They then multiply that number by the best estimate of the number of galaxies in the universe.
After all these calculations, NASA can only confidently say that the number of stars in this universe is immeasurable, so much that it cannot be counted.
A study by the Australian National University estimates that there are 70,000 million million stars in the universe.
4. The footprint that astronauts on the Apollo mission leave on the Moon will probably last for at least 100 million more years.
The moon has no atmosphere, no wind or water to wash away or fade away the marks of Apollo astronauts. That means footprints, rover wheel tracks, traces left by human spacecraft will be stored on the moon for a very long time.
The only thing that can erase these traces is the deposition of cosmic dust being sucked onto the surface of the Moon. Those are the “micrometer meteor “ repeatedly attack the Moon, but the process will take place very very slowly.
5. The Sun makes up 99% of the mass of the Solar System
Our star, the Sun, is so dense that it accounts for 99% of the mass of the entire Solar System. Mass is what allows the Sun to dominate all the planets, sucking them around.
Technically, our Sun is a G-type main-sequence star, meaning that every second, it will merge about 600 million tons of hydrogen with helium. It also converts about 4 million tons of matter into energy as a by-product.
When the Sun dies, it will become a red giant, bulging and devouring the Earth and everything on it. But don’t worry: It won’t be possible within 5 billion years.
6. The total amount of solar energy hitting the Earth every hour is more than the total energy the planet uses throughout the year
In the past century and a half, people are increasingly exploiting more solar energy to serve their lives. According to the 360 degree Yale Environment Magazine, in 2017, the world increased by 30% of solar power capacity, equivalent to 98.9 gigawatts of solar energy has been produced.
Even so, this is only 0.7% of the world’s annual electricity use.
7. If two metal elements of the same element touch each other in space, they will stick together and stick together forever
This amazing effect is called cold welding. It happens because the atoms on either side of two pure (undoped) metal fragments can no longer distinguish where they belong. Therefore, these atoms automatically bind to nearby atoms, which belong to the nearby metal fragment that makes them stick together.
The interesting thing is that cold welding never happens in Earth’s atmosphere, because there are always water and air molecules separating the two metal pieces, no matter how close they are to each other. .
Cold welding occurring in vacuum is an effect that has a lot of significance for the construction and repair of spacecraft and the future of vacuum construction.
8. The largest asteroid in our Solar System is a giant piece of space rock called Ceres
Ceres asteroid – sometimes called a dwarf planet – has a diameter of about 950 km. So far, Ceres is known to be the largest asteroid in the asteroid belt between Mars and Jupiter. It alone accounted for a third of the weight of the belt. The surface area of Ceres is approximately the area of India or Argentina.
There’s a human spaceship approaching and flying around Ceres, helping us discover its mysteries. Dawn, or the Dawn ship, was launched into space in 2007 and it took eight years to reach Ceres.
9. A day on Venus is longer than a year on Earth
Venus has an extremely slow axis rotation speed, taking about 243 days on Earth for it to complete an entire cycle. Ironically, a year on Venus is shorter than the period around its own axis. Venus only takes 226 Earth days to orbit the Sun.
If you lived on Venus, you would see the Sun rise every 117 days on Earth. That means the Sun will only grow twice in Venus’ year. In addition, because Venus rotates clockwise, the Sun will rise in the west and set in the east.
10. The Great Red Spot of Jupiter is shrinking
The giant storm on Jupiter, which can be seen through a telescope from the Earth like a Great Red Spot, is shrinking. At nearly 11 times the diameter of Earth, Jupiter may have storms that devour the three Earths in its heart. The Great Red Spot has been such a storm, but so far, its size has shrunk to just a third.
11. One of Saturn’s moons has two distinct tones
Iapetus, one of 62 moons of Saturn, is actually a rather unique celestial body. This moon has two very specific tones, with one side much darker than the other. This feature does not appear on any other moon in the Solar System.
Iapetus’s color must be related to its position relative to the rest of Saturn’s moons. Iapetus is located outside the Saturn belt and therefore, it is subjected to a lot of space debris that shoots to the surface, causing dark colors on one side of it.
12. The location of the North Star will change
It would be strange for a North Star to no longer be a North Star. But in about 13,000 years, scientists predict this will happen. In case you didn’t know, the Earth axis has undergone a movement called “precession”, meaning that it will gradually tilt to draw a cone, similar to the spinning top when it is about to fall.
When this happens, the stellar position of the North Star will deviate from the Earth, leaving it no longer stationary in the night sky in the northern hemisphere. At that time, we will have a new North Star.