Mars.
It's one of the places to be. At least if you are a space enthusiast. Many people in the space community have been longing for a Mars mission since the 1970s if not before. Once Apollo wrapped up, many people thought first we would return and establish bases on the moon and then launch Apollo style missions to Mars. That clearly did not happen.
None of the Presidents from the 1970s until the late 1980s wanted to do a major space mission. The country had other priorities and the race to the Moon was a Cold War stunt that had served its purpose. After Challenger blew up, President Bush (the elder) half heartedly pushed space once more. However, when it received a lukewarm reception in Congress, in no small part due to the increasing deficit and the recently raised taxes, he abandoned it. TBH, NASA had a significant portion of blame: rather than aim for one particular goal, like going to the Moon for a permanent base or a flags and footprints on Mars, they wanted to do everything. And they asked for everything.
After President Clinton was elected, he told the science community it had a choice: the NASA space station or the Superconducting Super Collider. NASA came out swinging and proposed their space station was an foreign policy and nonproliferation project: the aerospace engineers in Russia were without salaries because the Russian government was pretty broke (and broken) at the time after the Soviet Union fell. There was a real worry the engineers would go wherever in the world they were offered jobs. They couldn't all be hired into the US and European aerospace industry for security reasons, so why not pay them to build the space station? That relegated the SSC into the dust bin of history and devastated the particle physics community in the US.
When Bush the Younger was elected, we had a traumatic experience with 9/11 and he went from a isolationist to a war president. However, when the Columbia space shuttle disintegrated on reentry, he directed NASA to start planning a restart. The plan was to go to the Moon and eventually Mars (huzzah!). However, that plan wasn't quite funded the way it ought to be and then when President Obama was elected, he reset NASA again. Somewhat.
Obama revised NASA's plan (asteroid instead of Moon or Mars) and cancelled some of the bits Bush's NASA had been working on. The Ares I rocket was scuttled. The Ares V rocket became the Space Launch System. The Aquarius lunar lander was also cancelled. Something interesting happened though: Obama largely handed over running the agency, or setting its priorities and funding, to Congress. Which Congress has done and NASA has had the most consistent plans and budget since the Apollo days.
That said, the current Trump administration changed the ultimate goal back from the asteroids and Mars to the Moon. However, the funding hasn't really changed, budget items are simply relabeled, and Congress has been still steering the ship. The Gateway station, Orion capsule and space launch system are all still funded the same as they were before.
There has been a moderate controversy in the last six months that is political, but more so in the science community than in the usual congressional or other circles. This one has is about whether we ought to send people to Mars and whether or not we really ought to be colonizing Mars even if we do. Finally, it has been called into question whether or not it is feasible within several life times to even start terraforming Mars.
The first is what has been called Planetary Protection. The concern is not protecting Earth from alien invasions, but rather the concern we will contaminate Mars with our microbes. This will complicate (at best) detecting native life on Mars, if there was any. If you think Mars has life and it needs to be found, this is an imperative.
Planetary protection is what drives the second controversy in a big way: if humans go to Mars there will be no possible way to prevent earth based microbes from contaminating the surface. Period. Our habitats will leak. Our waste cannot be returned to orbit: Apollo left big bags of feces on the Moon, for example.
The Planetary Society has recently started arguing astronauts cannot go to the surface until we know whether or not have proof Mars does not have life. They believe it can be found with robotic probes better than with people and that people would simply contaminate everything. Bill Nye has even come out and questioned if people will ever live there and ever terraform it. He stated we can't take care of our own world, why did we think we could terraform another?
That ties into that last controversy. Evidence has been found both that Mars has a toxic soil - perchlorate salts make up .5% of the regolith (soil) - and Mars lacks the the necessary volatiles to terraform it even if we had the technology to do so. I've called Mars a megafund site. It is toxic and needs major upgrades: the volatiles needed are not present on Mars and the same mass as the kuiper belt object called Quoaor.
Circling back, planetary protection or preventing contamination of Mars my earth-life is almost assuredly already a lost cause. The Soviet Mars 2 crashed onto Mars in 1971 and it is highly likely it was not even remotely decontaminated as much as necessary. Mars 3 and Mars 6 followed to the surface as well in 1971 and 1973. The Viking landers were also not decontaminated to modern standards either. All five of these sites are probably contaminated and given the winds on Mars, it's highly likely the entire planet has been. Planetary protection is probably a moot point.
As for how nasty Mars is, that is actually correct. That may not stop those who want to escape Earth, like Elon Musk. People live in some pretty inhospitable environments. And while none are as bad a Mars, or even remotely so, people with motivation and money can probably overcome the problems though.
Likewise, it's also the only place we might possibly be able to terraform with technologies we can foresee within the next century. Even so, it will require an enormous effort. The only other possibility for a semi terraformed world to colonize would be Venus, but that would require floating cities. Terraforming Venus is far, far beyond what we can do. Mars is beyond what we can do now, but Venus is several orders of magnitude harder.
That said, once Mars is terraformed, it will not be a balmy tropical paradise. Mars only receives around 1/3 the energy from the sun that Earth does. While it is possible to have greenhouse gases that keep the planet warmer, that needs to be balanced with the fact Mars lacks a magnetic field and lower gravity, causing it to lose its atmosphere. The warmer the atmosphere, the faster Mars will lose it. Speculation would be to say the equator will have a climate like Seattle or Ottawa. It will get rapidly colder further north and south. The North will mostly be ocean, but the south below 50 deg south will probably be tundra, if not Greenlandic, when finished.
That will take centuries to get to though.
