This is a spoiler page for the puzzle The Observatory in the Ravensburger Exit / Escape-series.
Here is a link to a high-resolution photo of the finished puzzle.
There are 6 puzzles in the image.
Some letters have fallen off the wall. You can find the letters in image, and from the screws you can work out in what order the letters were:
Around the image there are also scraps of paper showing what letter corresponds to what number: R=4, L=2, S=6, A=3, E=9. Subtitute the numbers and do the addition:
23+6+94 = 123
Each constellation corresponds to a number, from 1 to 6. In the sky you can see the following constellations, from left to right: 1,2,6. (There’s an image where the constellations are highlighted on the Ravensburger help page). The solution is 126.
The paper on the table is a decoder. You get the value of each symbol by multiplying the x-axis with the y-axis. That way you get the following values:
First row: 1 (1×1), 2 (1×2), 3 (1×3)
Second row: 2 (2×1), 4(2×2), 6(2×3)
Third row: 3(3×1), 6(3×2), 9(3×3)
Now replace the symbols on the scarf with the corresponding numbers and do the addition:
For this puzzle you use the same decoder as in the prevous puzzle. Again, substitute the values and do the math:
3+1+4*6 = 28 (remember to do the multiplication before the additions)
Four planets are marked with symbols, and the same symbols can be found on the candles:
Each symbol corresponds to a number, and you can find those here:
Jupiter is 5, Saturnus 6, Uranus 7 and Neptune 8.
In order to know in what order to put these numbers, we need to go back to the candles. The length of the candles determines the order of the numbers. The longest candle bears the symbol for Uranus=7, the second-longest the symbol for Jupiter=5, the third-longest the symbol for Neptune=8 and the shortest has the symbol for Saturnus=6. The answer is 7586.
There are many books in the image, and many of them have two symbols on the spine. The object is to always find the following book in the series, and that is the book with the same symbol on top that the previous book had below. The answer is the number of books that are part of this series. The answer is 23.
The last book in the series is the orange one with the hashtag symbol.
User Puzzling2 sent in this graphic to show the sequence of the 23 books, making it easier to see the symbols:
The solution pieces form a laser beam.