1. In Egyptian Mythology, Ra is the name of the Supreme Deity. He created Heaven ((Nut) and Earth (Geb). He was the son of Ptah, brother of Toth, and the (Grand-) Father of Seth, Nephtys, Isis and Osiris. When he retired, he gave Seth rulership over Upper Egypt, and Osiris over Lower Egypt.
(Other Egyptian myths tell a different story: Ra was the son of Nun and Atum. He got two children, Shu and Tefnut, who became the parents of Nut and Geb. These two became the parents of Seth, Nephtys, Isis and Osiris).

Ra was the god of the sun during dynastic Egypt; the name is thought to have meant "creative power", and as a proper name "Creator", similar to English Christian usage of the term "Creator" to signify the "almighty God." Very early in Egyptian history Ra was identified with Horus, who as a hawk or falcon-god represented the loftiness of the skies. Ra is represented either as a hawk-headed man or as a hawk.
Owing to the fact that the sun was a fire, the Egyptians realized that in order to travel through the waters of Heaven and the Underworld, it required a boat, and so Ra was depicted as traveling in a boat. During the day the boat was a great galley called Madjet ("becoming strong") and during the night, a small barge called Semektet ("becoming weak").
During dynastic Egypt Ra's cult center was Annu (Hebrew "On", Greek "Heliopolis", modern-day "Cairo"). In Dynasty V, the first king, Userkaf, was also Ra's high priest, and he added the term "Sa-Ra (Son of Ra)" to the titulary of the pharaohs.
Ra was father of Shu and Tefnut, grandfather of Nut and Geb, great-grandfather of Osiris, Set, Isis, and Nephthys, and great-great-grandfather to Horus. In later periods (about Dynasty 18 on) Osiris and Isis superseded him in popularity, but he remained "Ra netjer-aa neb-pet" ("Ra, the great God, Lord of Heaven") whether worshiped in his own right or, in later times, as half of the Lord of the Universe, Amen-Ra.

Ra-Hoor-Khuit (Ra-Hor-akhuti).

"Ra, who is Horus of the Horizons." An appellation of Ra, identifying him with Horus, showing the two as manifestations of the singular Solar Force. The spelling "Ra-Hoor-Khuit" was popularized by Aleister Crowley, first in the Book of the Law (Liber AL vel Legis).

SEE ALSO Amon, Geb, Horus, Isis, Nephthys, Nut, Osiris, Set, Shu, Tefnut, Hor-akhuti / Horus.

[Source: Shawn C. Knight, "Egyptian Mythology FAQ" ]

2. Solara calls Alnitak, the third -and lowest- star in the Belt of Orion, RA.

Orion's Belt
Orion's Belt: Alnitak - Alnilam - Mintaka

"The RA lineage emanates from the Star system of Sirius. Due to the Sirian experience with the transformation from red sun to white star, they are the overseers of the coming shift in Solar rulership that will greatly affect our solar system.
The RA emanation is that of the receptive, the dream, the intuition, feelings and love. Although it may seem strange that RA contains qualities that are more lunar in nature, yet its symbol is the sun, all we can say, is that on this dimensional level the frequencies are reversed from what we experience on Earth. From RA originates the great starry dolphins and whales who send their brethren to Earth in order to aid in our enlightenment. Those of the RA lineage have often served as priests and mystics. RA is connected to Osiris." (Solara, The Star-borne, p. 245.)

Together with the other two stars of the Belt of Orion (EL and AN), Ra is part of an intergalactic gateway, called the EL*AN*RA.

3. The RA material also mentions a sixth dimensional group consciousness, called Ra or the Ra. They originially were a third density species that lived on Venus in the days that it was still inhabitable.