Scanning planets in Mass Effect 3 works slightly differently to that of 2 in that you don’t hunt for minerals; instead you send a probe into certain planets for assets such as artifacts, credits or even new War Assets.
Most solar systems also have Reapers hanging around the outskirts and if you scan too much, a bar will fill up and the Reapers will enter that solar system. They’ll speed up until their ships are faster than yours, so you need to hit the green outer-edge quickly to avoid dying.
Thankfully though, any planets or fuel wrecks uncovered by over-zealous scanning will remain open and if you complete a full mission, the Reaper awareness level will 'reset' back to zero, allowing you to go back into that solar system without any worries about being chased.
Our guide focuses on only the areas of each solar system that you need to scan, meaning that you shouldn’t ever have to worry about the Reapers showing up as you’ve got the most efficient scanning plan available to you here.
The solar system Asgard ** holds multiple hidden items - to reveal their locations, fly North of (and almost between) the planets Tyr and Borr to highlight both of them (along with a fuel depot worth 250 Units of Fuel ). Tyr ** holds a new War Asset - Alliance Naval Exploration Flotilla . The planet Borr ** holds the remains of a Reaper Destroyer (this will offer either 5% off Citadel purchases or you can add 5% to your Power Recharge Speed). The planet Terra Nova ** (found South-East of its sun) is hiding the War Asset - Alliance Cruiser Shanghai . The most Southern planet Loki ** contains the War Asset - Alliance Spec Ops Team Delta .
As there’s too many planets to scan in a single visit to this Solar System, we recommend you first scan Tyr ** and Borr ** for the Reaper Destroyer remains and then come back after you complete a mission to reset the Reaper’s awareness back to zero again (allowing you to scan the other planets for their War Assets).
There’s no Reapers near here and no assets to uncover either; just a Fuel Depot that allows you to refill your tank to the brim - for a price (works out at roughly 100 credits per 100 units of fuel needed).
The only thing in this galaxy is the Citadel with no hidden assets to uncover.
There’s a Fuel Depot ** located in the Trebia ** solar system, along with the moon Menae ** that’s holding the Turian Primarch (if you’ve still to do that mission). There’s nothing to scan for and no Reapers to worry about in here either.
The solar system Gemmae ** consists of a massive sun and whilst there appears to be nothing of interest here, if you scan the North-East corner of the solar system (beside the planet Pheiros ), you’ll uncover two hidden fuel wrecks (one with a whopping 800 units of fuel and the other with a very useful 750 units of fuel - so save one until you really need it). The planet itself holds the War Asset - Turian 79th Flotilla .
Castellus is comprised of many planets; the hidden fuel wreck is located near the far-right of the solar system (it holds 350 units of fuel ) and if you scan and probe the planet Digeris , you’ll be rewarded with a new Citadel artifact ’ Banner of the 1st Regiment '.
Set your sights to the 'Kite’s Nest' (South-East of the space map) and warp here to the Harsa solar system. Look for the Saturn-like planet known as Verush ** and scan this planet, revealing an item you can scan and collect (you’ll be rewarded with a Weapon Upgrade that provides either 5% more ammo or 5% more weapon damage). The scan will also have revealed a hidden haul worth 300 Units of Fuel . Now send a scan out when sitting on top of the planet Khar’shan and you can probe this planet for a new Journal/side-mission ’ Pillar of Strength '.
Go to the nearby solar system Untrel ** and ** scan just to the left of the planet Adek ** and you’ll uncover two hidden plots with a single scan. The planet itself holds 1 0,000 Credits whilst the other hidden area contains 100 Units of Fuel .
Vular ** has ** a ** hidden fuel wreck worth 150 units of fuel near the North-West corner of the solar system.
You’ll have almost alerted the Reapers with your scanning, so nip back out of this Solar System and head to ’ Hades Gamma ’ just to the North-East. In the Antaeus solar system scan the planet known as Trebin ** for a cool 10,000 Credits . There’s also a hidden wreckage with 300 Units of Fuel located just South-West of the Mass Relay ship (so don’t scan for it unless you actually need the fuel).
Fly across to the edge towards the Plutus ** solar system and in the upper-left corner scan the planet known as Nonuel . This will reward you with a new War Asset - Special Ops Team Zeta from the 103rd Marine Division. As that’s 100% of the assets recovered from this solar system, move on to the Dis ** system to the North. The planet Kensal ** to the North holds a sweet 10,000 Credits . To the East of its Sun you’ll uncover a fuel wreckage harbouring 200 Units of Fuel .
The Farinata ** solar system contains a couple of nearby locales if you scan in between its Sun and the planet known as Juntauma . It contains a new War Asset - Alliance First Fleet and the hidden location holds an additional 200 Units of Fuel for the journey back to the Mass Relay ship. But this single scan will **** fill up the Reaper Alertness bar by 3/4, so be sure you have enough fuel to escape if you alert them.
In the Cacus ** solar system you can scan the planet Chohe ** for 10,000 Credits and if you scan to the South of the green arrow leading to Dis ** you’ll uncover a fuel depot with 400 Units of Fuel for the taking.