How many planets have been discovered so far What were the first asteroids to be discovered

At the International Astronomical Union Congress held in Sydney on the 22nd, Australian astronomers said that there are about 700 trillion stars in the entire visible universe, that is, 1022 stars.

Even in the darkest part of the earth, only about 5,000 stars, including stars and some planets in the solar system, can be seen when looking at the sky with the naked eye, and only about 100 stars can be seen in brightly lit cities.

Using astronomical telescopes, Australian astronomers first select a small area of the universe for observation, measure the brightness of all galaxies in that area, and calculate the number of stars contained in all galaxies, and then use the results to extrapolate the number of stars in the entire visible universe. Astronomers believe that this figure is much more accurate than previous estimates.

The number of stars reported by Australian astronomers at the International Joint Astronomical Congress in Sydney can indeed be called astronomical. 700 trillion stars is the addition of 22 zeros to the number 7. That's more than all the grains of sand in the sands and deserts of the planet.

Dr Dryford of the Australian National University said: "The actual number of stars in the universe may be even larger than that, and may even be uncountable. He believes that many stars in the universe have planets, and that some of them may have life on them.

But because they are so far away from Earth, humans may never be able to have any contact with the creatures that live there.

According to the survey are 9 major planets, 4 minor asteroids.

Not a single one, because human beings haven't even discovered their own planets, let alone anything else, it's better to send a probe every day, it's better to help Africa.

The first asteroid to be discovered was Ceres.

Ceres is the smallest and only dwarf planet in the solar system located in the asteroid belt. Discovered by the Italian astronomer Piazzi and published on January 1, 1801.

Ceres is likely to be a divergent planet with a rocky rocky core, and the mantle layer contains a large amount of icy water, and it is now found that there are a large number of water-carrying minerals from the ground to the surface of the planet. It is tentatively speculated that water makes up 40% of Ceres' volume. Ceres can also obtain its energy from the sun, as it is only one AU from the Sun, compared to Europa and Enceladus, which are 9 AU away.

Categories: Science & Engineering.

Problem description: Is it true that scientists have discovered that the sun has 12 planets? What are they called?

Analysis: The original nine planets are Earth, Mercury, Venus, Mars, Saturn, Jupiter, Uranus, Neptune, and Pluto.

Three newly discovered planets (Ceres, Charon, Xena).

1) Ceres.

19 billion billion tons.

1205 km.

Discovered by American researchers in July 1978, Charon orbits in a circular orbit about 10,000 kilometers above Pluto's equator, with a period equal to Pluto's rotation. Observations in recent years have shown that Charon and Pluto form a double planetary system, rotating around the Sun synchronously.

2) Charon. 19 billion billion tons.

1205 km.

Discovered by American researchers in July 1978, Charon orbits in a circular orbit of about 10,000 kilometers above Pluto's equator, with a period equal to Pluto's rotational period. Observations in recent years have shown that Charon and Pluto form a double planetary system, rotating around the Sun synchronously.

3) Xena. The quality is unknown.

2400 km.

Brown, an astronomer at the California Institute of Technology, discovered an object at the edge of the solar system in 2003 and tentatively numbered it "2003UB313". In July 2005, Brown officially announced the discovery and called the object "Xena" (a mythical belligerent goddess). The sky ** is in the Kuiper belt outside Neptune's orbit, and according to experts, it is about 16 billion kilometers from the sun and its surface temperature is about minus 248 degrees Celsius.

Eight.

Until now, there were only eight planets known to mankind in the solar system. And Pluto certainly exists, but it is no longer classified as a planet as the ninth planet. This is not because astronomers discovered that Pluto does not exist, but because Pihu is because of the problem of planetary definition.

The eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Most of the rotation directions of the eight planets are also consistent with the rotation direction of the public sales. There are only two exceptions: Venus and Uranus. Venus rotates in the opposite direction to its revolution.

Categories: Education, Science, >> Science & Technology.

Analysis: The solar system is the star system we are in now. It consists of the Sun, 8 large planets, 66 moons, and countless asteroids, comets, and meteorites.

The planets from the Sun to the outside are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Mercury, Venus, Earth, and Mars, which are closer to the Sun, are called terrestrial plas.