The good news is you don't have to do this before Sol 100 (Although you probably will) so you can take your time battle through the tough early-mid game, then once you get towards the late game you should have plenty of resources (Build all the wonders!) to easily complete all goals.
To get 500% difficulty rating it takes into consideration:
* Your Faction: (Just choosing SpaceY puts you on 200% difficulty!)
* Your commander: Futurist is the most difficult which bumps you up to 260% but I went with Astrologist at 250% for them early deep scans. (Hydro engineer & Rocket Scientest are also 250%)
* Your mystery: Taking a hard mystery puts you on 310% difficulty. Marsgate is pretty easy, just make sure to research the tech straight away when it becomes available and build around 5 turrets at each side of your base to defend the attack. Although you can beat all goals before they attack.
Game Rules: You want to pick 3 tougher rules. I would reccomend choosing from Hunger (A farm a dome should be enough to keep the colonists fed), Inflation (Won't hurt you early game and by late game you should be either self sufficient or profitable) Long Ride (SpaceY have slightly faster rockets to offset this) and Rebel Yell (Rebel's aren't that bad, I'd reccomend filtering all rebels into 1 dome. They might blow up the occasional building but at least they aren't upsetting anybody else!)
3 of these 4 should take you to at least 440%
*Map Selection: Depending on what rules you picked just find a landing spot that takes the difficulty up to at least 500%
The Sponser Goals are:
Generate 100 Energy: Simple enough, you'll unlock this naturally.
Refuel a rocket the same Sol it lands: Again pretty simple. Once you get the the fuel requirements down to 30 make sure you have at least 30 fuel in stock then land at the beginning of the Sol close to the fuel and your drones should do the rest.
Research 8 Engineering technologies: Again simple enough, you should get this naturally.
Analyze 7 Planetary Anomalies: When you have a rocket land (and you have fuel available) just check whats anomolies are available in the Planetary view and send the rocket to complete 1. Repeat this 6 more times,
Have 3 Biorobotics Workshops: These are in the biotech tree, around 75% of the way down. Once you've researched the tech just build 3 as they should be the last goal you need.
As goals go, this is a pretty easy and straightforward list.
Once you start playing don't expand too aggressively. If you've been playing with preferable game rules in the past (100% difficulty) you'll notice things are a bit tougher. You'll get hit by more sand storms, cold spots etc. so make sure you have plenty of resources (Water/Oxygen/energy) saved up although you'll nearly always spring leaks that lose these resources during these disasters so be prepared and just expand naturally.
I unlocked this achievement early into the Marsgate mystery but if you are still playing when they attack just make sure you have enough turrets to protect the parts of your base that they are likely to attack from. I found grouping 4-6 turrets at either end of my colony was enough to fend off both waves.