Was Crocodile stronger at Marineford? Or was he holding back in Alabasta?

 During the Alabasta arc, Crocodile displayed a level of power that was initially considered overwhelming by the Straw Hat Pirates. He possessed the Logia-type Devil Fruit called the Suna Suna no Mi (Sand-Sand Fruit), which granted him the ability to control and transform into sand. He had a reputation as a Shichibukai and controlled the desert kingdom of Alabasta from the shadows. His strength was showcased through his battles with Luffy and others. At Marineford, Crocodile was present as part of the war that took place at Marine Headquarters. While he did participate in the battle, he didn't display the same level of dominance as some other powerful characters present. This has led fans to speculate that he might not have been as strong as initially portrayed in Alabasta. It's important to note that power scaling and character abilities can be subject to interpretation and development by the author. Oda often keeps details deliberately open-ended to keep the story intriguing.

Why did Alan Bean go into space twice (Apollo/Skylab)?

 Alan Bean was an astronaut who served as the lunar module pilot on the Apollo 12 mission in 1969, and later served as the commander of the Skylab 3 mission in 1973.

Bean was selected as an astronaut in 1963, and after completing his training, he was assigned to the Apollo 12 mission, which was the second manned mission to land on the Moon. On this mission, Bean and fellow astronaut Pete Conrad landed the lunar module on the lunar surface, and Bean became the fourth person to walk on the Moon.

After the Apollo program ended, Bean was assigned to the Skylab program, which was a series of manned missions to a space station launched in 1973. He served as the commander of the Skylab 3 mission, which was the second manned mission to the Skylab space station. During this mission, Bean and his crewmates spent 59 days in space, conducting a variety of scientific experiments and performing maintenance on the space station.

In total, Bean spent a total of 69 days in space over the course of his two missions. He retired from NASA in 1981 and later became an artist, using his experiences as an astronaut as inspiration for his paintings.