Just like bricks are the building blocks of a home, atoms are the building blocks of matter. Matter is anything that has mass and takes up space (volume). All matter is made up of atoms. The atom has a nucleus, which contains particles of positive charge (protons) and particles of neutral charge (neutrons).

All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, “matter” generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest …

Yes, all things are made of atoms, and all atoms are made of the same three basic particles – protons, neutrons, and electrons. But, all atoms are not the same. You know that the number of protons in an atom determines what element you have. They are the glue that holds atoms together in chemical bonds.

The smallest thing that we can see with a ‘light’ microscope is about 500 nanometers. A nanometer is one-billionth (that’s 1,000,000,000th) of a meter. So the smallest thing that you can see with a light microscope is about 200 times smaller than the width of a hair. Bacteria are about 1000 nanometers in size.

There are approximately 7 x 1027 atoms in the average human body. This is the estimate for a 70 kg adult human male. Generally, a smaller person would contain fewer atoms; a larger person would contain more atoms.

The First Humans One of the earliest known humans is Homo habilis, or “handy man,” who lived about 2.4 million to 1.4 million years ago in Eastern and Southern Africa.

However, stars like our Sun (1 solar mass) are quite common and so we can approximate the star formation rate to be about 3 stars (like our Sun) per year in our Galaxy. If we turn this around, this mean that throughout the entire Universe, a star is born every 0.0002 seconds (i.e. every 2, 10,000th’s of a second)!!

We estimate at about 100 billion the number of galaxies in the observable Universe, therefore there are about 100 billion stars being born and dying each year, which corresponds to about 275 million per day, in the whole observable Universe.

If the Universe holds enough matter, including dark matter, the combined gravitational attraction of everything will gradually halt this expansion and precipitate the ultimate collapse. Over time, galaxies, then individual stars, will smash into each other more frequently, killing off any life on nearby planets.

Most stars take millions of years to die. When a star like the Sun has burned all of its hydrogen fuel, it expands to become a red giant. After puffing off its outer layers, the star collapses to form a very dense white dwarf. …

about 5.5 billion years

supernovae

Telescopes have captured the rare light flash from a dying star as it was ripped apart by a supermassive black hole. (For comparison, the nearest star system to Earth – Alpha Centauri — is roughly 4 light-years away, and the Milky Way is roughly 200,000 light years in diameter.)

The period of the variations in KIC 9832227 has been observed to be growing shorter since 2013, leading to the prediction of the merger in 2022. The cause for the period variation is still unknown, but it is unlikely that the system will end in a merger at the predicted time.

According to study from a team of researchers from Calvin College in Grand Rapids, Michigan, a binary star system that will likely merge and explode in 2022. This is an historic find, since it will allow astronomers to witness a stellar merger and explosion for the first time in history.

Unfortunately, supernovae visible to the naked eye are rare. One occurs in our galaxy every few hundred years, so there is no guarantee you will ever see one in our galaxy in your lifetime. In 1987, a supernova called 1987A was visible in a nearby galaxy called the Large Magellanic Cloud.

While stellar collisions may occur very frequently in certain parts of the galaxy, the likelihood of a collision involving the Sun is very small. Astronomers say that if a stellar collision happens within 100 light years of the Earth, the resulting gamma-ray burst could possibly destroy all life on Earth.

Sound needs a medium to travel (such as air), but space generally doesn’t have it. Therefore, sound can’t really propagate in space. So you can’t hear an explosion or any other sound in space.