Space myths vs facts: 12 common misconceptions

Light doesn't escape a black hole because it's too slow, or because something is holding it back. It travels at its usual speed - but beyond the event horizon, every path leads not outward but inward. The direction "away" simply doesn't exist there.

The event horizon is neither a wall nor a surface. It is the line beyond which every path, including light paths, leads only inward. You can cross it without noticing, but seeing this from the outside is almost impossible.

The Moon does rotate on its axis - it just takes exactly as long as it does to orbit Earth. Earth's tides slowed it down this way. And because it wobbles slightly, we get to see not exactly half its surface, but about 59 percent.

Near the horizon, the Moon looks huge, while overhead it looks ordinary, even though its size in a photo is the same. This perceptual illusion has been known for thousands of years, and there is still no single explanation for it.

An Italian astronomer described fine lines on Mars and called them by a word meaning waterways or channels. In English, the translation became a word implying human-made structures - and for half a century, Mars became a planet with engineers.

The Sun doesn't burn - there is nothing there to burn, and no oxygen. In its core, hydrogen fuses into helium, and part of its mass becomes energy. The surprising part: per cubic meter, the core gives off less heat than your body. The Sun shines because it has an incredible number of those cubic meters.

In a few billion years, the Sun will use up the hydrogen in its core, swell into a red giant, and engulf the nearest planets. But life on Earth will become impossible much sooner: the Sun's luminosity is already gradually increasing.

A star's color is its surface temperature. A red one glows at about 3,000 degrees, a blue one at tens of thousands. The yellow Sun sits closer to the cool end of the scale than you might think.

Pluto didn't change or disappear. The definition of a planet changed because similar bodies were found beyond Neptune's orbit, and one of them turned out to be at least as large as Pluto. The choice was between a new rule and a growing list of planets.

Venus's surface is about +460 °C - hotter than Mercury, even though Mercury is nearly twice as close to the Sun. The reason isn't distance but air: it exerts more than 90 times Earth's pressure and is almost entirely carbon dioxide. It lets light through but barely lets heat escape.

It isn't matter flying away from some point. It's space itself expanding between galaxies. That's why expansion has no center: from any galaxy, the view looks the same, as if all the others are moving away.

There was no explosion in the usual sense. There was no point in empty space that burst, with fragments flying outward. There was a very hot, dense phase - everywhere at once - after which distances between everything began to grow. An explosion spreads out through space. Here, space itself is growing.