What does the star represent in Mormon temples?

Answer 1

Masonic SymbolsJoseph Smith, being a Freemason, adopted the Star and other Masonic Symbols to adorn LDS Temples.

ALTERNATE VIEW: While it is true Joseph Smith was a Freemason (of the York rite), it is unclear how much such an association would have influenced the design of the Nauvoo Temple in the early 1840s. Minutes from the Masonic Lodge "Under Dispensation" in Nauvoo during the time period show that Smith was not a regular attender of the lodge's meetings.One historian wrote: "It seams from the meager records that are extant, that Joseph Smith attended as many meetings on those two days [when he was admitted as a Mason] as he did during the rest of his lifetime" (McGavin, Mormonism and Masonry, 90). It must also be pointed out that construction of the Nauvoo Temple began prior to Smith's becoming a Freemason in 1842. Furthermore, Smith's followers constructed a temple in Kirtland, Ohio in the early 1830s. Other such edifices were planned in Independence, Far West, and Adam-ondi-ahman, all in Missouri, prior to the 1838 Missouri Mormon War. (The Kirtland Temple bears no clear symbolism of the star, moon, or sun.) This does not mean he could not have incorporated the star for reasons associated with Freemasonry, but it is unlikely. A more plausible explanation has already been noted below; that is, the star was most likely associated with the Mormon theology of the afterlife, specifically that of the telestial kingdom.

Answer

The five-pointed star was used in the Nauvoo Temple and other early temples, but it's meaning was wholesome. Inverted stars did not generally become associated with the occult until after the time of Joseph Smith. Stars, including inverted stars, were used by early Christians as valid Christian symbols. The symbol of the star - whether it has five or six points - and the pentagram can be used for good or evil purposes. The fact that Satan worshipers have given evil meanings to the star, the moon, or whatever does not make the symbols inherently evil.
Though the symbols in Masonry, and as seen upon some temples of the Mormons are the same and similar in some cases, it does not mean that the interpretation of such symbols are the same.
The symbols go back to time immemorial, and have been corrupted, and contain many errors or alterations. The Masons may have the symbols but their understanding of them is misunderstood, their signs are not used as part of holy ordinances, but as signs of recognition or some other use not related to gospel principles.
Every symbol on a Mormon Temple has the same meaning as it did when they were used in biblical times.

Alternate AnswerStars symbolize heavenly things, reminding us to lift our sights from worldly things and to consider things of eternal significance.

In Mormonism, they are likely to refer to the Telestial Glory, whose glory is compared to that of the stars, in contrast to Terrestrial Glory, which is compared to that of the Moon, and to the glory of the Celestial Glory, which is compared to that of the Sun. More on this can be found in D&C 76 and 1 Cor 15.
Christian Symbols Found in StarsThe star seen as a pentagram can also be found not only as a Masonic symbol but as a Christian symbol.
A particular meaning of the pentagram can be found within the story Sir Gawain and The Green Knight. The star in it's symbolism in this story represents the five wounds of Christ as well as the five chivalric virtues.