If you are of a mind to put the party in danger, how about suggesting a stroll across one of the deadliest regions of Mars, the TITAN Quarantine Zone?
Beginning with an explanation of what the Zone is and how it came to be, there are details of the terrain and major features as well as of the measures taken to ensure that the curious stay well out of it. This is intermingled with suggestions as to how these measures might be counteracted, although it will be up to you how you choose to pass on any ideas to your players if they are struggling to come up with their own - this is a book decidedly for the GM!
The hazards of the TQZ are extreme, even without the Patrol ready to pounce on intruders. Extensive jamming of all communication links render not just keeping in touch (or yelling for help) but navigation difficult. The terrain is rugged in the extreme, and prone to dust storms. All sorts of malevolent critters live there and even the artefacts that are the usual reason for anyone wanting to go there are dangerous if improperly handled (in many cases, if handled at all). A random encounter table and full notes on what you might encounter are provided to liven things up a bit.
Various locations are described, as are some of the TITAN artefacts that remain to be found - including quite an array of different drugs and addictive substances. Finally, there's a collection of plot hooks to get the party's interest in an expedition whetted enough for you to get to use all of this on them.
If you like adventures in which the environment is as much an enemy as the monsters, this is one to consider.