The show "Alien Contact," put forth the following difficulties in visiting our planet as near insurmountable.
The difficulties are numbered my thought while watching the show is in brackets;
1. Gravity their planet may be smaller and have less gravity could not walk on earth. (Gravity applies to anything that has a mass rest assured any planet with or without aliens will have gravity. NS did not say anything about what would happen if gravity on their planet was stronger therefore making it easier for them to move about on earth).
2. An alien ship may just burn up in Earth's Atmosphere upon entry. (They have traveled halfway across the galaxy to visit the earth, built an interstellar spacecraft and not slow down when they come into our atmosphere and burn up. What kind of sense does that make? We can be sure of 2 things, 1 The Alien planet will have an atmosphere of some sort very unlikely they have evolved in a vacuum . 2 If they can travel hundreds or thousands of light years we can safely assume they are smart enough to slow down or have a shield of some sort).
3. Bacterial Organisms, will kill the aliens when they land. (This is a possibility, once again bacteria are very common life forms and found everywhere on Earth. It's possible that fossil bacteria have been found on a meteorite which fell in Antarctica. No doubt Aliens will have bacteria on their planet as well. Unless of course their world is sterile and they have never encountered bacteria which is highly unlikely.)
4. Aliens would not know how to communicate with us on earth. (I don't know what an Alien world would be like, perhaps they only have 1 language. Aliens may not even use language and use only thought to communicate or music is another possibility. If an Alien will make an attempt to communicate with us I am sure we can work something out; that is if the Alien even wants to communicate with us. One common language we will have is physics, after all they did come in a spacecraft of some sort.)
5. Oxygen may be lethal to Aliens. (This is very true, any scuba diver will tell you that past 100 meters depth oxygen is poisonous. Whatever their atmosphere is does not logic dictate that they would know enough to have testing equipment and spacesuits if required)?
NS put forth the premise "If Alien technology is a Million years ahead of ours." Well if Alien technology is 1 million years ahead of ours and have worked out interstellar travel, would it be safe to assume that they have some knowledge of basic physics and the obstacles put forth by Naked Science are an obvious attempt to discredit the idea of alien visitors possibly visiting the earth. Once again they made the reference to the "Roswell Incident" the 1947 crashed of a supposed UFO in New Mexico. The US Government said it was a weather balloon. In 1995 the US Government said it was not a weather balloon but a radio balloon called Mogal. NS skeptic says yes the government lied and now told the truth. The problem I have with this is: That an Army Major in US Army Air Corp Intelligence cannot tell the difference between a balloon (Weather or Radio) and an aircraft / spacecraft of some sort? This is patently ridiculous. Obviously Naked Science does not think much of the intelligence of those watching the programs they produce.
The only reason that I gave this show a 3 was because of the theoretical physicist and the information he provided on warped space was interesting and correct.
NS has the opportunity to show groundbreaking views and insights into science. Instead the people that produced this show for some reason intended to serve as debunker's of Alien visitation using science without any logic or common sense to prove their point. From now on any NS show I happen see will be viewed with great skepticism. Obviously the show is geared for the uneducated that do not have any common sense whatsoever.