Star Trek has brought galaxies of wonder and amazement to fans for decades. The franchise has produced 13 films, eight live action series, and three animated series. One of the most popular Star Trek series was The Next Generation, which ran for seven seasons.

The Next Generation, Deep Space Nine and Voyager were all set during the same timeframe, allowing for more crossovers. But, with the use of alternate dimensions and time travel, as well as a belief that people will live longer as time goes on, opportunities have arisen for characters from The Next Generation to show up in other Star Trek series.

11 Jean-Luc Picard: Deep Space 9, Picard

Sir Patrick Stewart as Admiral Jean-Luc Picard

Captain Picard appears in the pilot episode of Deep Space 9, "Emissary." He is hated by Captain Benjamin Sisko because of his actions while assimilated as Locutus of Borg. Sisko blames Picard and his actions for the death of his wife, Jennifer.

RELATED: Star Trek: Most Important Space Stations, Ranked

Picard, of course, also returns as series regular in his own show Picard. It is set after the events of The Next Generation and follows the now-retired Admiral Picard on missions, even though he has become disillusioned with Starfleet.

10 William Riker: Voyager, Enterprise, Picard, Lower Decks

Jonathan Frakes as Captain William Riker

Commander William Riker has shown some of the greatest range of guest appearances. He appears as a witness in a trial on Voyager, in which Q summons Riker to the ship as Janeway must decide whether to grant asylum to a member of the Q consortium. Riker then appears in the controversial finale of Enterprise. It's set on the Enterprise's holodeck as Riker is studying the final mission of Captain Archer's crew.

Riker returns to Star Trek in Picard, where he comes to Picard's aide in the first season and then becomes a regular for the third season. Riker also makes an animated appearance in the first season finale of Lower Decks.

9 Q: Voyager, Picard, Lower Decks

John de Lancie as Q

Q is one of the easiest Next Generation characters to place in another show, since he can move flawlessly through space and time. He appears in three episodes of Voyager, and even hints that he can get the crew back to the Alpha quadrant faster than estimated.

Q also appears in the second season of Picard, when he sends Picard, Seven, Rios, Raffi, and Jurati back in time to try to ensure the timeline is protected. He hints that he will die when he sends them back to their own timeline. Q also makes an animated appearance in an episode of Lower Decks titled "Veritas."

8 Geordi La Forge: Voyager, Picard

Levar Burton as Geordi La Forge

Geordi is one of the best engineers in the Star Trek universe, but he appears as the Captain of the Challenger in the 100th episode of Voyager, "Timeless." In an alternate timeline, Geordi is trying to stop Chakotay and Kim from changing the past after Voyager crashed into an ice world. Geordi is sympathetic, but can't let them violate the Temporal Prime Directive.

RELATED: Star Trek: Most Powerful Klingon Starships, Ranked

Geordi returns in season three of Picard, trying to assist Picard and Riker on their mission to save Beverly Crusher and her son Jack. It's also revealed in the season the helmswoman of the Titan is Geordi's daughter, and the pair have a contentious relationship.

7 Deanna Troi: Voyager, Enterprise, Picard, Lower Decks

Marina Sirtis as Deanna Troi

Much like her husband, William Riker, Deanna Troi has appeared on several other series in the Star Trek universe. She appears in three episodes of Voyager. Deanna also joins Riker on the holodeck for the series finale of Enterprise.

She also appears in Picard at the Riker homestead as she helps Admiral Picard regain his bearings in the first season. She also joins Riker in an animated appearance in the first season finale of Lower Decks.

6 Data: Enterprise, Picard

Brent Spiner as Data

Despite being an android who could conceivably return more often, Data has surprisingly few crossover appearances. Part of that is due to him being destroyed in Star Trek: Nemesis, but the franchise's creators have found ways to bring him back. In his most controversial appearance, his voice can be heard in the holodeck in the series finale in Enterprise.

In the third season of Picard, Data is revived in a new synthetic body. His consciousness has been merged with Lore and B4, as well as with some memories of Dr. Alan Soong. Despite Data's few crossover appearances, Brent Spiner has appeared as other characters across the Star Trek universe.

5 Worf: Deep Space 9, Picard

Michael Dorn as Worf

Worf is one of the few characters from The Next Generation to become a series regular on another show. In the fourth season premiere of Deep Space 9, "The Way of the Warrior," Worf moves from life on a starship to life at a space station following the Klingon attack on Cardassia. He would remain on Deep Space 9 until the end of the show's run.

Worf returns in the third season of Picard, as a subcontractor of Starfleet Intelligence working with Ro Lauren and Raffi. He helps Picard and Riker in their battle with the Changelings.

4 Dr. Beverly Crusher: Picard

Gates McFadden as Dr. Beverly Crusher

Dr. Crusher had a long and illustrious Starfleet career, but as fans learn in season three of Picard, she and Captain Picard definitely explored their chemistry after the events of the series. Dr. Crusher is trying to protect her son from the changelings.

Dr. Crusher's appearance in the third season of Picard introduces her son with Jean-Luc Picard, Jack Crusher. The return of Gates McFadden is something fans had been clamoring for since Picard was announced, and season three delivered for them.

3 Miles O'Brien: Deep Space 9, Lower Decks

Colm Meaney as Miles O'Brien

Miles O'Brien is the case of a beloved minor character getting the chance to grow into a beloved major character. He served on board the Enterprise during The Next Generation, appearing in 50 episodes. Then, he makes the jump to Deep Space 9 in the series premiere, providing a connective thread between the two series.

O'Brien goes from being an everyman serving as Lieutenant on the Enterprise, to the Chief of Operations aboard Deep Space 9 and Chief Engineer on the Defiant when they had to leave the space station. His wife, Keiko, and daughter, Molly, join him on board Deep Space 9. A holographic statute of O'Brien also appears in Lower Decks.

2 Guinan: Picard

Whoopi Goldberg and Ito Aghayere as Ghinan

One of Jean-Luc Picard's most trusted advisers makes her return in the series that focuses on him after he has become disillusioned with Starfleet. Guinan appears in two different forms in season two of Picard.

RELATED: Most Powerful Women in Star Trek

Whoopi Goldberg appears as an older version of Guinan in the second season premiere, "The Star Gazer." Ito Aghayere then takes over the role on a recurring basis throughout the second season as Picard and his crew are sent back in the past to protect the timeline.

1 The Borg Queen: Voyager, Picard

Annie Wersching as the Borg Queen

While the Borg Queen is introduced in Star Trek: First Contact, she makes an appearance in subsequent Star Trek series. She appears in multiple episodes of Voyager, tying her assimilation connection to Seven of Nine.

She also returns in the second season of Picard, where she is vital to the crew being able to travel back in time to find the point where the timeline was changed. Dr. Jurati ends up assimilating and becoming the new Borg Queen, allowing the Borg to help Picard when he returns to his own timeline.

MORE: Star Trek: Most Powerful Empires, Ranked