Orb

Orbs, also known as Tears of the Prophets, were mysterious artifacts that originated from non-corporeal entities known as the Prophets, who resided inside the Celestial Temple (aka the Bajoran wormhole).

Overview
Central to the Bajoran religion, nine different orbs have appeared in the skies above Bajor in the past ten thousand years. According to Bajoran legend, they were sent by the Prophets to provide guidance and wisdom.

Appearing as hourglass-shaped energy fields, the Orbs defied conventional scientific analysis. They produced temporary but intense metaphorical hallucinations on people in the immediate vicinity, which seemed to be a form of direct or indirect communication with the Prophets. However, only individuals whom the Prophets permitted experienced these visions. These orb experiences often provided some form of personal insight or divination into the future, and many were recorded in the form of ancient Bajoran prophecies. After an encounter with an Orb, individuals sometimes experienced continued visions known as orb shadows. Bajorans believed that Orb shadows resulted when individuals ignored what their Orb experience had told them.

As tangible objects offering communication with their gods, the Orbs were greatly treasured by the Bajoran people. The Orbs were contained inside ornate, jeweled vessels tended by monks, safeguarded inside monasteries. A force field also protected the Orb inside its vessel. Officially, contact with an Orb required the special permission of the Vedek Assembly, although this was a rarely-followed formality.

Despite their appearances, the Orbs were not purely energy fields; they had a physical presence. An unknown Orb was damaged at some point in Bajoran history, a fragment of which served as the jewel in a bracelet. This bracelet was kept in Faren Kag's village on Bajor, where it was wielded by the Sirah. The Sirah used this bracelet to create a creature called the Dal'Rok, and focus the collective energy of the villagers to defeat it. 

During the Cardassian occupation of Bajor, all but one of the Orbs were stolen and taken off-world for study, although the Cardassians never unraveled their purpose or function. The remaining Orb was hidden away by Kai Opaka, and later given to Benjamin Sisko, who she knew was to become the Emissary of the Prophets. The formal peace treaty signed between the Cardassian Union and the Bajoran Provisional Government in 2371 did not resolve the issue of returning the lost Orbs to Bajor, although several were returned under various other circumstances in the following years.

In 2374, a Pah-wraith carried inside Dukat entered the Celestial Temple through the Orb of Contemplation, causing all the Orbs to go dark. This led to widespread panic among the Bajorans, who believed that their gods had forsaken them. The Orbs were restored three months later by the discovery of the previously unknown tenth Orb, the Orb of the Emissary, by Benjamin Sisko on the planet Tyree.

Orbs

 * Orb of Contemplation
 * Orb of Prophecy and Change
 * Orb of Time
 * Orb of Wisdom
 * Orb of the Emissary (not one of the original nine orbs)

In addition, a number of fake orbs have cropped up over the years. 

Background Information
In regard to why Bajorans didn't consult the Prophets more frequently, Ronald D. Moore commented: "We assume that not everyone has access to the Orbs whenever they have a question about their relationships (Shakaar was the First Minister after all, and rank hath its privileges) and also that the messages from the Orbs are often murky or confusing and may not always provide the clearest answers in matters of the heart."

Moore had also said that it is a "distinct possibility" that the Prophets have also sent Orbs to other races in the Gamma Quadrant.

Apocrypha
In the Deep Space Nine book trilogy Millennium, the Pah-wraiths built three orbs of their own, known as the Red Orbs of Jalbador. When these three Orbs were brought together, they opened a second Celestial Temple.

In the Deep Space Nine Relaunch novel Avatar, Book One, the Orb of Memory was found aboard a derelict Cardassian freighter in the Badlands. This Orb demonstrated the ability, when left open, to make all those aboard the freighter uncontrollably contemplate past events, to the point at which they completely lost track of their mission. When in close proximity it also allowed Elias Vaughn to experience the memories of the dead crew of the freighter and see a vision of Benjamin Sisko. Later, in Lesser Evil, the Orbs of Destiny, Souls, Truth, and Unity were returned to the Bajoran people by a joint effort between the Cardassian Oralian Way (a religious movement) and Vedek Yevir Linjarin. All nine orbs were later moved to Ashalla, the capital city on Bajor in Unity.

In Star Trek Online, another orb is mentioned, the Orb of Possibilities. For a limited time, upon completing the 2800 Featured Series, the player could receive a shard of the orb, known as the Shard of Possibilities.