The image is a combination of data from two satellites. This true-color image shows North and South America as they would appear from space 22,000 miles (35,000 km) above the Earth.

For humans and the other things living on our planet, practically the entire cosmos is a hostile and merciless environment. Earth is a tiny, fragile exception in the cosmos. It just so happens that things live here and the environment near the surface of this particular planet is hospitable for life as we know it. But Earth is a planet, and it’s in space and part of the universe just like the other planets. Humans say “out in space” as if it’s there and we’re here, as if Earth is separate from the rest of the universe. In fact, you’re technically in space right now.

About 8,000 miles (12,800 kilometers) below your feet - on the opposite side of Earth - lurks the unforgiving vacuum and radiation of outer space. Day or night, whether you’re indoors or outdoors, asleep, eating lunch or dozing off in class, outer space is just a few dozen miles above your head. Wherever you are right now, outer space is only 62 miles (100 kilometers) away. Though the universe may seem a strange place, it is not a distant one. On the nebula's younger left side, many stars are just beginning to clear away the gas and dust. The dust and gas in the region are swept around even more when those stars die and explode as supernovas. The cavernous red region on the right side of W51 is older, evident in the way it has already been carved out by winds from generations of massive stars (those at least 10 times the mass of our Sun). 'Star factories' like this one can operate for millions of years. The star-forming nebula W51 is one of the largest 'star factories' in the Milky Way galaxy.

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