More than is known is unknown. It’s because we know how much dark energy it affects the expansion of the Universe. It’s a complete mystery, besides that. It is a major mystery, however. It turns out to be about 68% dark energy in the universe. One reason for dark energy is that it is a space property. Albert Einstein realized… Read more →
A white hole is a strange cosmic entity that glows brightly and emits stuff rather than disappearing. To put it another way, it’s the polar opposite of a black hole. Unlike black holes, however, there is no agreement on whether white holes exist or how they develop. Einstein’s theory of gravity predicts them, and they’re most commonly cited in the… Read more →
Before a man’s sperm can fertilize a woman’s egg, the head of the sperm must attach to the outside of the egg. Once attached, the sperm pushes through the outer layer to the inside of the egg (cytoplasm), where fertilization takes place. Sometimes the sperm cannot penetrate the outer layer, for a variety of reasons. The egg’s outer layer may… Read more →
White dwarfs are dead stars. A single white dwarf contains roughly the mass of our sun in a volume no bigger than our planet. Our sun will become a white dwarf someday. White dwarfs are the hot, dense remnants of long-dead stars. They are the stellar cores left behind after a star has exhausted its fuel supply and blown its… Read more →
There are two basic types of sleep: rapid eye movement (REM) sleep and non-REM sleep (which has three different stages). Each is linked to specific brain waves and neuronal activity. You cycle through all stages of non-REM and REM sleep several times during a typical night, with increasingly longer, deeper REM periods occurring toward morning. Stage 1 non-REM sleep is… Read more →
Railway sleepers, also called railroad ties, railway ties or crossties, are an important railway component. Generally, the rail sleeper is always laying between two rail tracks to keep the correct space of the gauge. In recent time, concrete sleepers are widely used, especially in Europe and Asia. And in the UK, steel ties are common. Besides, plastic composite ties are… Read more →
When a spacecraft is launched into orbit, it should end up spinning around the Earth quickly enough not to be pulled back in by the Earth’s gravity. The huge rockets used in launching a spaceship help this to happen by giving a huge amount of thrust, enough to achieve escape velocity. However, the spin of the Earth itself can help… Read more →
Alcohol is older than the Great Pyramid at Giza, the Roman Colosseum, Machu Picchu, the Taj Mahal, and the Great Wall of China combined! Before the 1850s, there were no “left” and “right” shoes; they were identical. Ancient Romans used crushed mouse brains as toothpaste. In 1895 there were only 2 cars in the entire state of Ohio yet they… Read more →
Identical twins indeed share their DNA code. This is because identical twins were formed from the same sperm and egg from their father and mother. (In contrast, fraternal twins are formed from two different sperm and two separate eggs.) Usually, the egg and sperm come together and create an embryo, which eventually grows into a human baby. However, in the… Read more →
A dream includes the images, thoughts, and emotions that are experienced during sleep. Dreams can range from extraordinarily intense or emotional to very vague, fleeting, confusing, or even dull. Some dreams are joyful, while others are frightening or sad. Sometimes dreams seem to have a straightforward narrative, while many others appear to make no sense at all. Many suggest that… Read more →
