I just love Sandler in this register. It’s no longer a surprise when he pulls a well-defined and memorable dramatic performance. Now, 189 days into his mission, Jakub Prochazka (Adam Sandler), the forlorn cosmonaut protagonist of “Spaceman,” is hurtling toward Jupiter to study the mysterious Chopra cloud. He is nearing his breaking point. Short on sleep in a malfunctioning spacecraft that has seen better days, what’s really occupying his mind isn’t the mission at hand — it’s the radio silence by his pregnant wife Lenka (Carey Mulligan). Despite efforts by his physician Peter (Kunal Nayyar) and Commissioner Tuma (an under-used Isabella Rossellini) at Mission Control to calm his fears, Jakub knows something is wrong. When a giant primordial spider named Hanus (voiced by Paul Dano) appears in his spacecraft, Jakub doesn’t know if the arachnid is real or a figment of a tired, desperate imagination. With the spider’s help, Jakub may just learn the secrets of the universe and of himself.