Nuclear powered?
When you say nuclear powered, are you talking about nuclear powered ion drives, nuclear explosion propulsion, nuclear thermal propulsion, nuclear ramjet, fission-fragment propulsion, or something else?
What kind of propulsion (nuclear-ion) do the top researchers think is a viable source of power needed to get there?
You can, and people have, reached Mars with conventional chemical rockets.
Nuclear isn’t necessary.
Yes, but a non-sucky way to get humans there would be nifty. Who wants to be stuck for months on end in a flying single-wide mobile home?
What if we figure out a way to control fusion such that we can fuse any amount of hydrogen we want—will that solve our problems? At 100 miles per second a trip to Mars will take 4.24 days. That’s accelerating at one g for about four and a half hours, coasting in free fall for 3.86 days, and spending another 4.5 hours decelerating. Wiki says we should have a handle on the problem by the year 2050.
what??? astronauts have flown proximal to another planet? maybe you’re talking about unmanned probes that fly mainly on inertia from the time they slingshot out of the earth’s gravity and whose rockets burn out once they reach mars. a manned voyage requires power at least to slighshot back to earth.
The OP never mentioned manned flight.
It’s strongly implied in the phrases “…get us to Mars” and “…get there”. I mean, If I tell a taxi driver “get me to Pockleton!” and he just takes my suitcase there, I’ll be a trifle disappointed.
got it. but you said ‘people have’ reached… but then it ended ‘…with conventional chemical rockets.’ no grammar error in your part. it just confused me.
With a good library and nice enough TV/home theater and movie collection, I’d be happy as a clam. 
But anyway, how feasible is it to use conventional means and have prelaunched fuel cells waiting along the route to Mars. Then the craft could dock with the waiting fuel cell, get a good burn to accelerate, then dock to the next waiting cell? Or would maneuvering/docking offset any gains?
I imagine the waiting fuel cell would have to be travelling at same speed to be efficient, and how to get that up to that speed? Hmmm…
Some type of nuclear propulsion sounds promising, but you aren’t going to see a nuclear powered rocket blast off from the earth anytime soon. The contamination from an explosive accident is too great. We’ll have to come up with a safer way to transport the fuel up into orbit, or maybe send up raw uranium which is pretty safe to handle, and process it into fuel way up in orbit. Assuming even that’s allowed.
Dammit, I want to see an Orion launch!
Well, maybe not in person, but from a continent or two away.
You can get to Mars with chemical rockets, nuclear rockets and solar thermal rockets. How much you can place on the group once you get there is the bigger question.
This is a bit dated now, but since it seems to have been key in driving mission profiles to get to Mars since it was written it’s worth a read - R. Zubrin and D. Weaver "Practical methods for near-term piloted Mars missions
You’d have to pack me in there with Ashley Judd and an endless supply of beer before I’d even think about it. And beer is heavy. Unless somebody can figure out a way to convert aluminum to propulsion, Ashley and I are never leaving Earth orbit.
Jump Gate? Creates a worm hole.
Currently science fiction. But, it would be the most practical way to get there quickly.
“Impossible” and “practical” are usually considered to be at odds with each other.
Judging by sci-fi, movie, and video game history the last thing you want to do is make experimental portals that are in any way involved with Mars, unless you want to open the gates to hell.
It didn’t look too bad from watching Spaceballs.
That’s pretty cool. Just a little longer than it took the Apollo missions to get to the moon. And, our astronauts would get the luxury of normal earth gravity for 9 hours of that trip.
That said, what are some good bets on sustaining that kind of acceleration/deceleration?
Anti-matter rockets. Because they are the coolest of the at the edge of possible propulsion systems.
Also, what about man-power? No, seriously.
Once we reach a trajectory with conventional rockets, or whatnot, the human body it pretty efficient an converting calories into work, yes?
As ridiculous as it sounds (yet I’m thinking of the accumulative effects of an ion drive), let’s take a crew of six, and have two stationary bikes, hooked up to a motor, that would transfer pedaling to thrust. Let’s say you schedule a rotation of biking, at least 25 mph, constantly… how long would that take to reach a velocity in the realm of 50 to 100 miles per second?
They have to exercise any way. But how much more food/water?