Poland cannot into space is a running gag in the Polandball series that is based in Polandball's attempts to venture into space. Polandball's attempts always end in some sort of mishap preventing the desired goal of heading into space from happening. He got to and landed on space once, but fell back to Earth.
It serves as a standard and classic way for countries to make fun of Polandball, one of the meme's most core principles. It has been elaborated on to extremities, has seen countless puns made based on it, and - in an event that astonished much of Polandball's followers, and cemented its popularity - is even an achievement in the video games "Europa Universalis IV", "Sid Meier's Civilization V: Brave New World" and "Hearts of Iron IV" .
Origins of the joke
"Poland Cannot Into Space" is a classic joke that originated on the Krautchan imageboard along with Polandball. One of the most common ways of making fun of Poland was pointing out how poor of a country it was compared to larger economies like Russia and the United Kingdom. Therefore, people poked fun at Poland for being not only technologically underdeveloped, but being unable to go to space, like every other country in the world. (Which is not true, as Poland has active, although small space program and had sent an astronaut under USSR project. It also has slightly higher GDP (PPP) per capita than Russia.) Like many jokes in Polandball, it is tongue-in-cheek satire of the person making the joke. It also appears in other versions such as "Poland Cannot Into Woman"
Why Poland cannot into space?
The reason why Polandball "cannot into space" is unknown.
A common theme in Polandball comics is for Austriaball to explain the logic behind the Polandball universe satirically (under the title "Dr. Österreich"). One comic by a redditor states that the reason is because everything in Poland is upside-down, which is also the reason why Poland's flag colors are seen inversely from its real ones in all proper Polandball comics. Later in the comic, further referencing his Freudian stereotype, Austria begins to spontaneously declare that Poland is a stupid country with a bad economy that is hated by God.
Dr. Österreich notes in another comic that Polish physics differ from the physics of other countries, resulting in Poland's upside down orientation. And, as mentioned, because of this, it would be extremely hard for Poland to float in space. His conclusion is that Poland's physics are so different from that of any other country (not on the level of Israelcube and Tringapore, of course.) that it is impossible for Poland to into space. This theory failed once, but because two USAballs pushed him, Polandball fell back.