The crew of the Jupiter 2 had two styles of flight suit (or space suit) during their adventures. These silver body suits were worn almost exclusively aboard ship, although they were occasionally worn out of doors immediately after landing on a planet or immediately prior to take off.
The first season flight suits were silver material backed with heavy canvas and had velcro closures. They were very snug and could make normal movement difficult. There are some photographs of cast members on the set resting against reclining boards because sitting was uncomfortable in their flight suits. Because of their heavy backing, these costumes were also very hot under the studio lighting.
The second season saw the earlier flight suits replaced by ones made from Mylar. These provided a sleek fit and the cast found them far more comfortable. An interesting note is that the first season suits were very similar in appearance to those worn by the astronauts of the Mercury and Gemini missions launched by the United States in the early 1960’s.
Aside from being “work wear” aboard ship, the flight suits also functioned as space suits. The familiar red padded vest-like yoke, with breathing apparatus mounted on the back and an attachment for the space helmet on top were added to allow crew members to engage in extra-vehicular activity. John, Maureen, Don, and even Dr. Smith went outside the ship while in space at least once each.
Nightwear made regular appearances throughout the series as well. Dr. Smith wore a striped nightshirt and nightcap; the children and Maureen wore pyjamas. Don West and John Robinson were never shown in pyjamas. Whenever they were dressed in pyjamas, characters also had on dressing gowns and slippers. In the scenes where the slippers were visible, they tended to match the colour of the character’s p.j.’s. Although Maureen and the girls wore button-up-the-front pyjamas, Will’s were the pull-over “polo” style.
In addition to their everyday clothes and working clothes, there are a number of occasions when individual characters sport very different styles. In “Wish upon a Star” and “Space Beauty,” Judy is seen wearing rather glamorous gowns. Penny, in “Princess of Space,” is dressed in full royal regalia.
All of the male characters except Dr. Smith are shown working in their undershirts several times over the course of the series. Piqué thermal undershirts seem to be standard issue in Alpha Control. The women were very rarely shown without their tunics; when they were, they wore short-sleeved or sleeveless blouses.
To round off the list, Dr. Smith also sported a straw boater in “Space Circus” and a pith helmet on a number of occasions, and in “Cave of the Wizards” Dr. Smith is seen wearing a skullcap representing an alien royal crown. Even the Robot wears a (traditional) crown in “The Mechanical Men.”