I had heard somewhere that one can purchase a star in honor of a loved one. Can you please supply me with the name of such an organization or refer me to one that could help me?
Unfortunately it's not really possible to officially "purchase" a star for someone, although many people think so and there are companies that advertise this service. The International Astronomical Union (IAU) is the organization that is responsible for naming celestial objects, and they don't take requests from anyone (even astronomers) for star names. There are places where you can "buy a star", and you will get a certificate and star maps, but these names are not official and are not used in astronomy. In fact, the companies that do this don't even make an effort to communicate with real astronomers on the subject, they just keep a big book or spreadsheet with everyone's name in it. Also, a lot of times the star you are given will be very dim, or even not visible to the unaided eye. A lot of people e-mail us asking how to find stars that they have "purchased", and it turns out that you need a telescope to see them, if you can even find the one dim star in a field of view full of other dim stars.
Most people in astronomy, especially the IAU, consider the "star purchasing" idea to be a huge scam that is taking advantage of people's love of the sky to make a lot of money. And in fact the NYC Department of Consumer Affairs (in 1998) issued a large fine to the major star-selling company for "engaging in a deceptive trade practice." But as long as you know that it's not official and don't mind, I think it's fine. After all, it expresses the same sentiment regardless of how official it is. However, I also agree with Dave Kornreich who said in a previous response to this question: "Why pay someone else to pick your star? Why not go out on a nice, clear night, pick one for yourself, and make your own certificate?" That way you can be sure that your star will be visible and it's one that you both like, and it will cost far less money.
If you would like a memorial for a deceased loved one, you might also consider making a donation to a local public organization or charity. Some of these accept donations in exchange for an engraved name somewhere that you can visit, and the money will go to a good cause. Or, if you just want a special gift for someone you know who loves astronomy, there are many museums, planetariums and space websites that sell books and posters with amazing images and information about space, and these places will give you something real for your money!
Anyway, sorry to possibly disappoint you, but many people really believe that this process is official and then are angry when they find out later that their name is not actually used by astronomers. For more information about this service, you can look at the IAU website , the Straight Dope website, and this Wired News article (from 2001) that has an interview with a vice president of one of the companies. If you want to find the place that sells them, I'd look up the International Star Registry on the web. I think it's about $50 to get a kit.
This page updated on June 27, 2015