Given the materials and technology available to us today, we would probably not survive on the sun. Conditions on the sun are quite extreme. First of all, the temperature at its surface is about 10,000 degrees Fahrenheit -- we would probably burn to a crisp almost instantly! Furthermore, the gravity of the sun is about 28 times that of Earth's gravity; we would be crushed by this! Also, the sun emits various kinds of particles (protons, electrons) and radiation (UV) that would do a lot of damage to our bodies.

Although few things are strictly impossible, surviving on the sun is certainly impossible today. First, the surface temperature of our sun is about 6 000 degrees Celcius (10 000 F). That's a bad start. After worrying about bursting into flames, you'd have to worry about being crushed by the gravity and atmosphere, dying from lack of oxygen, and dying from all the high-energy radiation.

No, we cannot survive on the sun. The temperature on the surface of the sun is hot enough to ionize matter: the sun is made of plasma. Molecules of any kind are broken apart and the electrons stripped off of the nuclei of the atoms. Because all life as we know it is composed of molecules, the sun is utterly inhospitable to any life that we are familiar with.