You will be able to see Datacrons from quite a distance as they emit a large glow around them and shoot a beam of light into the sky. If you are very close to a Datacron you will also be able to hear the sound from them.
Datacron Locations By Planet
Hoth – 5 Datacrons
Red Matrix Shard
Location: -735, 1702
This Datacron is a breeze! Head to Highmount Ridge located south of Leth Outpost. This Datacron is sitting out in open at the coordinates. Enjoy!
Orange: Cunning +4
Location: 3143, 471
Head to the Star of Courscant and get to the second floor. At coordinates 3248, 493 you will find a group of boxes that you can use to work your way to this Datacron. You may have to wait for the boxes to come your way before you can jump up on them. If you are having trouble finding the Star of Courscant its located in the lower right portion of the Starship Graveyard on your map.
Yellow: Presence +4
Location: 1041, -1245
Head to Frostwake Outpost and travel due north towards the top of your map. You will see this Datacron on the side of a hill. At first glance it appears to be unobtainable. If you travel to coordinates 1145, -995 you will find a ledge you can jump onto. Follow the ledge until it ends. From threre you can jump down, stay as close to the wall as possible. You will land in near a cave. Follow the path through the cave to collect your Datacron.
Green: Endurance +4
Location: 2837, -374
This Datacron can be a bit tricky and requires some climbing. Head to coordinates 2607, -844 and start jumping / climbing up the ice. Eventually you will end up above what appears to be an ice bridge. Drop down onto the ice bridge. Follow the path as far as you can, again you will need to do some jumping / climbing. When you reach the appropriate level your Datacron will be waiting for you!
Red: Strength +4
Location: 2992, -89
To get this Datacron you must first kill the Ancient Probe Droid and loot a “depleted Datacron”. Then head to coordinates 2850, -109 inside the Starship Graveyard. You will notice some pipes on the wall, on the right hand side, start climbing up them. At the top of the pipe, jump off onto the top of the wall and follow the path. At the end of the path is another pipe you can jump down on. From that pipe you can drop down to the Coupled Recharge Station. Use the keyboard there and shazaam! Datacron!