The color of blood can vary greatly among different species, including potential extraterrestrial species. While human blood is indeed typically dark red due to the presence of the iron-containing protein called hemoglobin, the color of extraterrestrial blood is purely speculative since we have no confirmed knowledge of its existence or characteristics. In science fiction and imaginative depictions, authors and creators have often portrayed extraterrestrial creatures with a diverse range of blood colors, including blue, green, purple, and even unconventional colors like orange or gold. Therefore, it is possible to imagine an extraterrestrial species with blood that could be colored #FF0000, similar to Karkat Vantas, a character from the webcomic "Homestuck." However, it's important to note that this is purely fictional and speculative, as we currently lack any empirical evidence of actual extraterrestrial life.