Naming a star after a loved one might sound like the perfect romantic gift. Purchasing real estate on the moon might seem like a worthwhile investment.

But can you really name a star or own part of the moon? Yes, and no.

What's in a name?

The names of astronomical objects are agreed upon by the International Astronomical Union (IAU). The organization is the recognized authority for naming celestial bodies, and it doesn't sell naming rights for stars, galaxies, planets or any other astronomical feature.

While some stars have names, such as Betelgeuse and Sirius, most stars are simply assigned coordinates and a catalog number.

With hundreds of millions of known stars, this is the most practical way to easily identify each individual star.

So what exactly are those companies that sell naming rights to stars offering you?

According to the IAU, such companies can provide you with "an expensive piece of paper and a temporary feeling of happiness."

Each of these star-naming companies maintains its own private database of stars and their names. They'll send you a certificate and instructions for finding your star in the night sky, but the IAU will have no record of name you've bestowed upon your star, nor will the organization recognize it.

Because multiple star-naming companies exist, it's likely that your star will even be given a different name by another company.

Out-of-this-world real estate

Do a quick Web search and you'll find numerous companies offering you the opportunity to purchase land on the moon, Mars, Venus and other planets, but can you really own an acre of the moon?

Dennis Hope says you can.

In 1980, the Nevada-based entrepreneur claimed ownership of the moon after finding a "loophole" in the 1967 U.N. Outer Space Treaty.

While the treaty forbids the Earth's nations from making territorial claims on celestial bodies, it doesn't address what claims an individual or private company can legally make.

So Hope claimed ownership of the moon in 1968 — as well as Mars, Mercury and Venus — and began selling space real estate through his company, Lunar Embassy.

He's now sold millions of acres of extraterrestrial land and says that so far, no government has challenged his right to sell the cosmic real estate.

While single acres sell well, he's also sold nation-sized parcels and says that his largest buyers have included 1,800 corporations, including two U.S. hotel chains.

Upon purchasing any of Hope's space real estate, he'll send you a deed, a map of your land and your planet's constitution and bill of rights.

Naturally, the moon — or planet of your choice — also comes with its own currency, and Hope has even gone so far as to make overtures for the moon to join the International Monetary Fund.

But there are some areas Hope won't sell for any price, such as the Apollo landing sites and the "Face on Mars."

"It would be irresponsible of the Lunar Embassy to sell these historic areas of general interest," according to the website.

Still, the IAU says purchasing extraterrestrial real estate legally gives you no claim to the land.

"Like true love and many other of the best things in human life, the beauty of the night sky is not for sale, but is free for all to enjoy," its website reads.

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