Can we ever reach other solar systems or even Mars?

"Every vision is a joke until the first man accomplishes it; once realized, it becomes commonplace.

–Response to a reporter's question following criticism in The New York Times, 1920" (Wikipedia, Robert Goddard)

That is a good question. That depends on what the word "ever" means. If we determine the word "ever" in human lifetime we face one interesting thing. Maybe we who were born in the 20th century will not see that Mars trip happen. And it takes a far longer time to create a large-size stable colony. In the same way, we cannot think that things like Alcubierre's drive will not complete our lifetime. 

Manned journeys to other planets than Mars are possible. But the risks are too high. Or the journeys to other planets than Mars, Venus, and Mercury take too long. And we cannot expect that people would spend lots of time in their lifetime in some spacecraft. Jupiter is too far for even the nuclear rockets and all nuclear rockets are CAD images on computer screens. And maybe we will not send the interstellar probe to Alpha Centauri in the next 200 years. Those things are purely theoretical. 

But then we can look at history. We must realize that airplanes or heavier-than-air aerial vehicles flew first time in 1903. The Russian researcher Konstantin Tsilokovsky (1857-1935) made theories about flight outside the atmosphere in the late 19th and early 20th centuries. That man introduced the idea of the space elevator. In 1945 Arthur C. Clarke (1917-2008) introduced a model of geostationary satellites. Making communication satellites possible.  

Chinese invented rockets in the 13th century. The thing is that Robert H. Godard (1882-1945)invented the liquid-fueled rockets. However, the Chinese invented the powder rockets hundreds of years before Goddard. 

The Chinese used rockets in the 13th century. 

"Robert Goddard, bundled against the cold weather of March 16, 1926, holds the launching frame of his most notable invention—the first liquid-fueled rocket."  (Wikipedia, Robert H. Goddard)

"irst successful flight of the Wright Flyer, by the Wright brothers. The machine traveled 120 ft (36.6 m) in 12 seconds at 10:35 a.m. at Kill Devil Hills, North Carolina. Orville Wright was at the controls of the machine, lying prone on the lower wing with his hips in the cradle which operated the wing-warping mechanism. Wilbur Wright ran alongside to balance the machine, and just released his hold on the forward upright of the right wing in the photo. " (Wikipedia, Wright Flyer)

"The starting rail, the wing-rest, a coil box, and other items needed for flight preparation are visible behind the machine. This is described as "the first sustained and controlled heavier-than-air, powered flight" by the Fédération Aéronautique Internationale, but is not listed by the FAI as an official record." (Wikipedia, Wright Flyer)

"V2-Rocket in the Peenemünde Museum" (Wikipedia, V-2 rocket)

"The Apollo 11 Saturn V rocket launch vehicle lifts-off with astronauts Neil A. Armstrong, Michael Collins and Edwin E. Aldrin, Jr., at 9:32 a.m. EDT July 16, 1969, from Kennedy Space Center's Launch Complex Pad 39A." (Wikipedia, Saturn V)

"The Space Shuttle Discovery and its seven-member STS-120 crew head toward Earth-orbit and a scheduled link-up with the International Space Station. Liftoff from Kennedy Space Center's launch pad 39A occurred at 11:38:19 a.m. (EDT). Onboard are astronauts Pam Melroy, commander; George Zamka, pilot; Scott Parazynski, Stephanie Wilson, Doug Wheelock, European Space Agency's (ESA) Paolo Nespoli and Daniel Tani, all mission specialists." (Wikipedia, Space shuttle)

Above: SpaceX Starship

2013 Lockheed Martin concept image of the SR-72 (Wikipedia, Lockheed Martin SR-72)

Artist's concept of a Skylon reaching orbit (Wikipedia, Skylon)

"The Nuclear Engine for Rocket Vehicle Application (NERVA) was a nuclear thermal rocket engine development program that ran for roughly two decades. Its principal objective was to "establish a technology base for nuclear rocket engine systems to be utilized in the design and development of propulsion systems for space mission application" It was a joint effort of the Atomic Energy Commission (AEC) and the National Aeronautics and Space Administration (NASA), and was managed by the Space Nuclear Propulsion Office (SNPO) until the program ended in January 1973. SNPO was led by NASA's Harold Finger and AEC's Milton Klein." (Wikipedia, NERVA)

NASA artist rendering, from 1999, of the Project Orion pulsed nuclear fission spacecraft. (Wikipedia, Project Orion (nuclear propulsion)

Daedalus spacecraft concept. (Wikipedia, Project Daedalus)

Robert H. Goddard (1882-1945) made the world's first liquid-fueled rocket in the year 1926. In fact, things like V-2 (A-4) rockets and the Saturn V rockets used a similar fuel pumping system. That Goddard used in 1926. So Wernher von Braun didn't invent liquid fuel rockets. But then we must remember that in the 1970's things like space shuttles were science fiction. Things like hypersonic flight in the atmosphere were hype in the 1990's and today there are plans for making hypersonic aircraft. 

The hypersonic shuttle can use scramjet engines in the atmosphere. Then the iris at the front of the scramjet will close. And the system starts to pump internal oxygen to those engines. That can make the new types of space shuttles possible. When we think about advances in rocketry we must realize that the Musk's SpaceX Starship project has one problem. Musk's Starship is so noisy. The next revolution can be the airplane that can raise airborne from regular airports. Fly to the edge of space. And then launch their rocket engines. 

But then to the interstellar and interplanetary journeys. The fact is that the safety of nuclear rockets is problematic. There is the possibility of making interplanetary probes that use things like an antimatter-cathode engine. That engine creates anti-electrons called positrons in the particle accelerators that are connected to its solar panels. The other track drives electrons against those positrons. 

The system can inject some propellant like hydrogen, water, or hydrocarbon into the combustion chamber. Those systems can open our path to the entire solar system. But stars are too far for us. As we have seen from history. Technology advances very fast. And maybe our grandchildren can make the interstellar probes possible. 

Advanced robotics and AI make it possible to create unmanned systems that can travel hundreds of years. Those systems can travel to other solar systems in time when their creators already die when they arrive. Then sooner or later we or our descendants must make the choice. Will they die when the sun grows into a red giant? Or will they travel into the other solar systems? Or maybe they can create a system that allows them to transport themselves into the past? That system can be the large-scale Tipler cylinders. But who knows the future? 

https://en.wikipedia.org/wiki/Alcubierre_drive

https://en.wikipedia.org/wiki/Arthur_C._Clarke

https://en.wikipedia.org/wiki/British_Aerospace_HOTOL

https://en.wikipedia.org/wiki/Konstantin_Tsiolkovsky

https://en.wikipedia.org/wiki/Lockheed_Martin_SR-72

https://en.wikipedia.org/wiki/NERVA

https://en.wikipedia.org/wiki/Project_Daedalus

https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

https://en.wikipedia.org/wiki/Robert_H._Goddard

https://en.wikipedia.org/wiki/Rocket

https://en.wikipedia.org/wiki/Saturn_V

https://en.wikipedia.org/wiki/Scramjet

https://en.wikipedia.org/wiki/Skylon_(spacecraft)

https://en.wikipedia.org/wiki/Space_Shuttle

https://en.wikipedia.org/wiki/Spaceplane

https://en.wikipedia.org/wiki/SpaceX_Starship

https://en.wikipedia.org/wiki/V-2_rocket

https://en.wikipedia.org/wiki/Warp_drive

https://en.wikipedia.org/wiki/Wright_brothers

https://en.wikipedia.org/wiki/Wright_Flyer