Old School RuneScape Wiki
Old School RuneScape Wiki
Instruction manual.png
This quest has a quick guide found here.
It briefly summarises the steps needed to complete the quest.


Start point Talk to the Observatory professor in the Observatory Reception Room south-west of Ardougne, north of Castle Wars. Talk to the Observatory professor in the Observatory Reception Room south-west of Ardougne, north of Castle Wars.
Official difficulty Novice
Description The Observatory in south-west Ardougne has been ransacked by a family of nearby goblins. Can you help the professor to rebuild it?
Length Short – Medium
  • 10 Crafting icon.png Crafting
  • The ability to defeat a level 42 monster.
Items required


Enemies to defeat Goblin guard (level 42) (Optional - can simply be trapped behind a column)

Getting started

The start of the quest.

Items required: 3 regular planks, a bronze bar, molten glass

Speak with the Observatory professor, located in the reception room of the Observatory (near the Observatory tower). Ask if you can look through the telescope and he says that it's broken. He tells you that a family of goblins has tampered with the telescope, so ask if you can help. He says that he needs some wood for the tripod, bronze for the tube, and glass for a new lens.

Once you have these three items, bring them back to the professor who will take them from you. He then says that he needs a mould so that he can make a new lens.

Note: Make sure to talk to the professor three times and give him the molten glass, bronze bar and three planks before attempting to inspect the stove; otherwise, you will have to lure or kill the guard again for the key.

Retrieving the lens mould

Items required: None.

Recommended: An antipoison potion, energy potions, combat equipment (for lower levels) and food

The stairs (red). The superantipoison (green).

If you don't have antipoison potions, you can pick up one Superantipoison at the spawn in the southeastern building. Go down the stairs to the east of the reception room to find the Observatory Dungeon (the room with the stairs is directly east of the start point).

A map of the Observatory Dungeon.

Once down the stairs, you must find the goblin kitchen key. It is commonly found in the south-eastern most chest although it can vary from person to person. Search any chests you pass on the way to the south-eastern chest just in case. Keep searching the chests (refer to the map) until you find the key. Be sure and click "continue" on the dialogue box or the key will not be added to your inventory.

Sometimes there may be a poisonous spider inside the chest in which case run away quickly or you may get poisoned. There is also a chest north-east of the stairs to the Observatory, which spawns infinite Antipoison(1) vials, which you can combine to make full vials. Consider using this moment to create yourself a stock for future use.

Now that you've got the key, head all the way back to the kitchen gate that you may have passed (take the northeastern path from entrance), and "prod" the sleeping guard. He will wake up and attack you. You can either defeat him or get him stuck behind a wall.

Note: Getting him stuck behind a wall will allow you to go through the door. However, if you pass the goblin again, you will be attacked. Also, another goblin will spawn asleep. You can fight multiple goblins.

Open the kitchen gate (you will use the key and discard it), and then inspect the goblin stove. You determine the goblins are cooking something foul in the lens mould. Dump out the stew and bring this back to the professor.

His assistant will ask you not to give it to him, as last time the professor attempted to craft something, the explosion took a week to clean up. The professor agrees and gives you back the molten glass and mould.

Use the molten glass with the lens mould to craft him a new lens. Give it back to the professor. He will want you to visit him in the Observatory.

The Observatory

The Observatory.

Items required: None.

Climb back down the stairs into the maze. Now, instead of taking the south-east path, follow the north-west passage (past the kitchen) to find some stairs leading to the Observatory. A cutscene will play. After the cutscene ends, go up the stairs and talk to the professor, and then "view" the telescope to see a constellation.

Looking through the telescope.

After closing the window, the professor should ask you which constellation you saw. The constellations are on wall charts in the main level of the Observatory. Identify your constellation, talk to the professor again, and you should get your reward in your backpack.

Congratulations! Quest complete!

Name & Reward Picture Name & Reward Picture
25 Water runes, uncut sapphire
Star Chart Viewer Aquarius.png Aries
875 Attack experience, uncut sapphire
Star Chart Viewer Aries.png
Amulet of defence, uncut sapphire
Star Chart Viewer Cancer.png Capricorn
875 Strength experience, uncut sapphire
Star Chart Viewer Capricorn.png
Black 2h sword, uncut sapphire
Star Chart Viewer Gemini.png Leo
875 Hitpoints experience, uncut sapphire
Star Chart Viewer Leo.png
3 Law runes, uncut sapphire
Star Chart Viewer Libra.png Pisces
3 Tuna, uncut sapphire
Star Chart Viewer Pisces.png
Maple longbow, uncut sapphire
Star Chart Viewer Sagittarius.png Scorpio
Weapon poison, uncut sapphire
Star Chart Viewer Scorpio.png
Super strength(1), uncut sapphire
Star Chart Viewer Taurus.png Virgo
875 Defence experience, uncut sapphire
Star Chart Viewer Virgo.png


Observatory Quest reward scroll.png


  • If the player talks to the Observatory assistant after the quest, he will give the player a jug of wine as thanks for the help. He will also tell the player his and the professor's real names, which are Patrick and Mamo-duna-roona, respectively