In space, there are clouds that contain gas and dust ejected from stars. Our solar system was formed 4.6 billion years ago from such a molecular cloud. Most of these dust grains were destroyed during solar system formation. The dark areas in this image of the Carina Nebula are molecular clouds. NASA, ESA, N. Smith (U. California, Berkeley) et al., and The Hubble Heritage Team (STScI/AURA)However, a very small amount of the grains survived and remained intact in primitive meteorites. They are cal ...read more
The fact that most humans spend most of their time indoors is not a subject of great debate. In contrast, archeologists agree that Neanderthals spent most of their time outdoors, so what were their living . Scientists have evidence dating Neanderthals to more than 520,000 years ago. They believe Neanderthals originated in Africa and then migrated to Europe. They went extinct around 40,000 years ago.They left little behind for scientists to analyze. Although some ancient skeletons have bee ...read more
We’re lucky to live on a water world. More than 70% of the Earth’s surface is covered in water.Earth is about 94 million miles from the Sun. That’s within the Goldilocks zone: the place in our solar system where a planet has just the right temperature for water to exist in oceans and rivers as a liquid and as ice in the north and south poles.Earth also has an atmosphere more than 6,000 miles (9,650 kilometers) thick that’s filled with oxygen for us to breathe. This atmosphere, along with ...read more
Sneezes have taken on many meanings throughout human history. Early Christians considered them divine signs or devilish tricks, while the ancient Greeks interpreted them as omens, both good and bad. But modern science has replaced all those superstitions with a physiological explanation: Sneezing is an integral part of the immune system, responsible for kicking out any material that tries to enter the body via the nasal passage. It’s essentially a defense mechanism, guarding against germs and ...read more
Elon Musk recently pronounced that the next Neuralink project will be a “Blindsight” cortical implant to restore vision: “Resolution will be low at first, like early Nintendo graphics, but ultimately may exceed normal human vision.”Unfortunately, this claim rests on the fallacy that neurons in the brain are like pixels on a screen. It’s not surprising that engineers often assume that “more pixels equals better vision.” After all, that is how monitors and phone screens work.In our n ...read more
Author Vishay SinghPosted on Categories Discover Magazine