In 2012, commemorating the 100th anniversary of the sinking of the Titanic, James Cameron launched a 3D edition  of his well-known film. The movie had one single change since the first edition in 1997. Thanks to the insistence of the director of the Hayden Planetarium in New York, the famous popularizer Neil deGrasse Tyson, the sky Rose contemplates towards the end of the film, when floating on a wood after the collapse, is finally the right one. Or so we thought. But let us remember the story from the beginning.
deGrasse Tyson didn’t have it easy to have Cameron change the sky:
James Cameron bragged about having taken pains to reproduce all the details of that trip, to the millimeter. But the sky showed in that sequence was not the right one. And, as Tyson account, the problem was not only that the sky was not the one it looked at the time. What is worse, they placed a sky made listlessly. Many parts are just a reproduction mirror of others. Here it is.
At the insistence of deGrasse Tyson, James Cameron postproduction team got in touch with him. And asked him to send the sky that could be seen in the site of the sinking of the Titanic on April 15, 1912 at 4:20 am. And this is what they sent from the Hayden Planetarium:
Hence, this was the sky in the new version of the film:
A really cool sky in which we can recognize many constellations.
But it has a serious problem. They placed the image of the sky showing a world map, with edge constellations distorted. It is very evident in the Square of Pegasus, top right. A square deformed to become a diamond. And the real sky is not like that. Let’s check it in detail:
Unless we are extremely purists, it isn’t too serious a problem. The sky, in general, is well represented. Buuuut…
It is very easy to reproduce the April 15, 1912 sky with a software as popular and easy to handle as Stellarium. The wreck site coordinates are 41 ° 44m N, 49 º 57m O. Be careful with the time. At the time of the sinking, the Titanic was at UTC -3. It must be entered explicitly in the software, which takes, by default, the time of your computer. This is the sky visible at that time and place.
There is a gross error. Incomprehensibly, in the sky sent from the Hayden Planetarium to Cameron team the brightest object there was at that time in the sky was lacking: Jupiter! With a magnitude that haunted the -2, it had to draw a lot of attention on that darkening sky. It was between Scorpius and Ophiuchus, in the left side of the image.
1 As explained by Neil deGrasse Tyson, the change of the sky was made for an edition of the film to mark its tenth anniversary, in 2007. We could not find that version. That is why we show the sky shown in the 3D version, 2012.
(taken from Naukas)