Going to space is one thing, but making an interplanetary travel is another much more difficult.
Going into space is relatively easy. We do this many times every year. We discovered this technology about a century and a half after we began to make practical use of electricity. While the electric bulb was invented in 1800, the first rocket carrying a satellite was launched in 1957.
On the other hand, we only have technology to travel between planets in our solar system, being impossible to go to planets located near another star, even relatively close.
The distance between the stars is enormous. The space is very large. So how is it possible to travel between planets located in different solar systems?
In the full versionf of the book (De)Constructing Physics (http://physicsebook.heliohost.org/) a new physical theory is revealed, making it possible. I suggest you read it.
In this book it is proved that space is discrete and contains energy, and this energy gives it a shape, that inertia is a property of this space and not of matter itself and that time is a function of temperature (the higher the temperature, the faster the time passes, and conversely, the lower the temperature, the slower the time passes, so that in a negative temperature – in Kelvin – the time arrow reverses allowing us to travel back into the past), being the destiny of the Universe a function of the amount of energy they contain.
Of course, this implies that future and past coexist being the future predetermined. Therefore, the predetermined future will interfere with the present to make it real. In this sense, everything exist at the same time and it is only our consciousness that moves in time, which implies that our free will is limited.
You need to read the whole book from chapter one in ascending order to understand everything correctly.
Basically, even traveling at the speed of light, the nearest star is about 4 years away. Therefore, making it impractical to make space travel using current physics. To do it properly you need to use space portals or subspatial travel as explained in the book. Using the subspace we can travel from one place to another instantaneously, without spending time.
Space bending technology helps, but not solve the problem, because this technology can only reduce travel time by a constant factor, not being a very advanced technology when we are talking about space travel, the subspace travel is the only answer.
Any civilization that can arrive in our planet should have developed some technology to make a space travel using the subspace, and must have discovered the theory explained in the book, except if they live within our solar system.
How to make an interplanetary travel using the subspace is a process that uses an enormous amount of energy, because it is necessary to disconnect from the space to be able to move without interference of the inertia, allowing us to quickly accelerate and decelerate. Therefore, the spaceship should be able to produce a lot of energy in a short time to make this travel possible.
Therefore, it is necessary to create a very powerful and reliable power source that produces a lot of energy with little fuel, like an anti-matter reactor.