With the decrease of solar activity, the magnetic field of oursun is losing power too. This heliosphere shields us forming a gigantic bubble which surrounds and protects our solar system from harmful galactic cosmic rays, these high-energy particles that zip through the universe. Thanks to Voyagers 1 leaving the Solar system, we now have a good vision of it and of its shielding effect. It appears to be an indispensable protection for our fast moving throughout the Universe. But, with a weaker heliosphere Earth will begin to endure more and more the cosmic rays.