Water on Mars is much less abundant than it is on Earth, at least in its liquid and gaseous states of matter. Most of the water known is locked in the cryosphere (permafrost and polar caps), and there are no bodies of liquid water which could create a hydrosphere. Only a small amount of water vapor is present in the atmosphere.

Current conditions on the planet surface do not support the long-term existence of liquid water. The average atmospheric pressure and temperature are far too low, leading to immediate freezing and resulting sublimation. Despite this, research suggests that in the past there was liquid water flowing on the surface, creating large areas similar to Earth's oceans.

There are a number of direct and indirect proofs of water's presence either on or under the surface, e.g. stream beds, polar caps, spectroscopic measurement,eroded craters or minerals directly connected to the existence of liquid water (such as goethite), grey, crystalline hematite, phyllosilicates, opal, and sulfate. With the improved cameras on advanced Mars orbiters such as Viking, Mars Odyssey, Mars Global Surveyor, Mars Express, and the Mars Reconnaissance Orbiter pictures of ancient lakes, ancient river valleys, and widespread glaciation have accumulated. Besides the visual confirmation of water from a huge collection of images, an orbiting Gamma Ray Spectrometer found ice just under surface of much of the planet. Also, radar studies discovered pure ice in formations that were thought to be glaciers. The Phoenix lander exposed ice as it landed, watched chunks of ice disappear, detected snow falling, and even saw drops of liquid water.

Michio Kaku (加来 道雄, Kaku Michio^?, born January 24, 1947) is an American theoretical physicist, the Henry Semat Professor of Theoretical Physics in the City College of New York of City University of New York, a co-founder of string field theory, a futurist, and a "communicator" and "popularizer" of science. He has written several books about physics and related topics; he has made frequent appearances on radio, television, and film; and he writes extensive online blogs and articles. He has written two New York Times best sellers, Physics of the Impossible (2008) and Physics of the Future (2011). He has hosted several TV specials for BBC-TV, the Discovery Channel, and the Science Channel.

Kaku was born in San Jose, California to Japanese immigrant parents. His grandfather came to the United States to take part in the clean-up operation after the 1906 San Francisco Earthquake^{[citation needed]}. His father was born in California but was educated in Japan and spoke little English. Both his parents were put in the Tule Lake War Relocation Center, where they met and where his two brothers were born.

William "Bill" Maher, Jr. ( /ˈmɑːr/; born January 20, 1956) is an American stand-up comedian, television host, political commentator, author, and actor. Before his current role as the host of HBO's Real Time with Bill Maher, Maher hosted a similar late-night talk show called Politically Incorrect originally on Comedy Central and later on ABC.

Maher is known for his political satire and sociopolitical commentary, which targets a wide swath of topics including religion, politics, bureaucracies of many kinds, political correctness, the mass media, greed among people and persons in positions of high political and social power, and the lack of intellectual curiosity in the electorate. He supports the legalization of marijuana and same-sex marriage, and serves on the board of PETA. He is also a critic of religion and is an advisory board member of Project Reason, a foundation to promote scientific knowledge and secular values within society. In 2005, Maher ranked at number 38 on Comedy Central's 100 greatest stand-up comedians of all time. Bill Maher received a Hollywood Walk of Fame star on September 14, 2010.