Dragon's Egg is a 1980 hard science fiction novel by Robert L. Forward.

It is a first contact story about humans meeting the [[StarfishAliens Cheela]], a race of beings who live on the surface of a neutron star. Both races live at a different time frame - twenty-nine seconds for a human is the rough equivalent of a year for a Cheela. Was followed by a sequel, ''Starquake''.

Notable as a hard science fiction story in that the science tends to be the focus.

!!Tropes in this book:

* AliensNeverInventedTheWheel: Wheels are never mentioned in the book: the Cheela use sleighs. While it's not explicitly stated, it's easy to surmise that, in the neutron star's extreme gravity, a technology where some part -- such as an axle -- needs to be lifted off the ground is not practical.
* AlternativeNumberSystem: The Cheela use base 12, since they have 12 eyes.
* AncientAstronauts: That is, we are. The arrival of the human spacecraft is so slow from their standpoint they worship it as a god. By the time we actually make contact, the Cheela are a little smarter.
* AntiGravity: One of the first things the Cheela invent on their own that is a technology beyond our own. Notably, they develop it before flight -- it's actually the basis of their aerospace engineering, since in Dragon's Egg's gravity you can't get airborne without it.
* BizarreAlienBiology: The Cheela aren't even made from ''normal'' matter.
* BlobMonster: The Cheela are sort of like amoebas.
* ContrivedCoincidence: The humans meeting up with the Cheela right as they developed society. If the trip had been scheduled just a few weeks (or days!) earlier the humans may have missed them. A few weeks later and the Cheela may have developed some tech already on their own.
* CrystalDragonJesus: The story of Pink-Eyes.
* ExtraEyes: 12, in a circle.
* FigureItOutYourself: After cheela science advances far beyond human knowledge, they give the humans an encyclopedia... of entries encrypted using keys based on the new scientific knowledge in the files. For instance, the explanation of {{faster than light travel}} is encrypted with a key engraved on an object placed in another star system. Thus, the humans need to figure things out for themselves, but when they do the files will confirm that they got the right answers and perhaps provide additional details.
* FirstContact: Humans meeting the primitive Cheela.
* FirstContactMath: How the humans contact the Cheela.
* FlatCharacter: The humans in this story who are visiting the Cheela have a few simple characteristics, but are nothing more than a device to bring the Cheela in. The Cheela are far richer characters.
* HeavyWorlder: One of the most extreme examples.
* [[ImAHumanitarian I'm a Cheelatarian]]: The Cheela think absolutely ''nothing'' of eating their dead.
* InnocentAliens: The Cheela have as many differences between them as any race, but they don't mean any harm to humans.
* MinovskyPhysics: Pretty much all of the human technology that didn't already exist when the book was written is based on [[http://en.wikipedia.org/wiki/Magnetic_monopole magnetic monopoles]], particles that are actually discussed by RealLife physicists (though they remain hypothetical for now). Forward explains in great detail the physics behind the monopole-using tech. Which brings us to...
* MohsScaleOfScienceFictionHardness: A 5.5. It's considered to be a fine example of hard sci-fi.
* NoAntagonist: In terms of the overarching plot of FirstContact. The Cheela go through a great deal of time and conflicts happen in each time period, but there is no BigBad in the book.
* APupilOfMineUntilHeTurnedToEvil: Averted. The humans upload their encyclopedia to the Cheela who quickly outpace humans, but they take on the role of a good teacher instead.
* ScavengerHunt: The Cheela eventually surpass humanity and give them the secret of interstellar travel [[spoiler: but in it's encrypted with the key listed as "written on a pyramid on the fifth planet of Epsilon Eridani".]]
* SpaceElevator: The Cheela need one of sorts to get off of the star.
* StarfishAliens: The Cheela are like amoebas, only with 12 eyes on stalks.
* TechnologyLevels: Mostly averted. The Cheela's technological development is very loosely patterned after the mankind's, but their different environment imposes important differences. See AliensNeverInventedTheWheel and AntiGravity above for more.
* TechnologyMarchesOn: A bit for the humans, a ''lot'' for the Cheela.
* TimeStandsStill: That's about how the humans look to the Cheela.
* TwentyMinutesIntoTheFuture: The first human time is the year 2000 in a book written in 1980. There's not a lot of tech development though there are no personal computers and no internet. The idea of ''any'' computer time being a valuable resource you have to pay for time on in the year 2000 is kind of funny in retrospect.
* YearInsideHourOutside: For every twenty-nine human seconds, about a year goes by for a Cheela. (Reading this out loud at a normal pace from "YearInsideHourOutside" to this point takes about six months of Cheela time.) A Cheela lifetime runs about 90 "greats" (approximately forty-four minutes) on average. One human character goes to bed annoyed that he'll be asleep for the Cheela equivalent of a millennium.