There are no photographs of the first stars, so we move too fast to see these.
Hubble and ESO sources have been used for the earliest galaxies, from 13 billion years ago.
The Sloane Digital Sky Survey
(SDSS) is used for background and some foreground planes for the rest of the journey until we reach our Milky Way, and then as background for the Milky Way. Hubble, the European Southern Observatory (ESO), and others are used for high-resolution foregrounds of galaxies and nebulae.
Many sources are used for the journey from edge of the solar system to surface of Earth.
There are actually three teams working on the opening section. The Hubble/ESO high-resolution foreground object team led by Jason Harwell
started work in mid-2012 and ended up with a five-person team that finished work in mid-2015. It includes an astronomer, Dr. Steve Danford, the head of the physics department at the University of North Carolina, Greensboro (in my home town), who supervised making things accurate, and is an official science advisor to the film.
The current SDSS team is led by Bill Eberly. Six others, including me, have contributed to that team. Another couple of physicists work on that team especially to help with very complex astrophysics mathematics involved.
The final team is the animation team. Well, team in this case means me. I always hoped to get animation help, but it turns out this type of animation is very hard, and there is no reason anyone else would want to learn it, since it can’t be used anywhere else. So I’m the sole animator on the film.
The process began by choosing our flight path through the universe, which is also a journey through time. We mapped out where and when in the universe all of the high-resolution sources we had available were located (allowing only those we could process in a “reasonable” amount of time). We then compared this to the areas of the Universe for which there was enough SDSS data to fill the backgrounds. It was actually a very complicated process to figure and map out in such a way that we could visualize it.
Once we had a flightpath, Jason’s High Resolution Team processed the planes of the destination galaxies and nebula along the flight path. They worked with Dr. Danford to be sure that their layers worked as accurately as possible, given our current scientific knowledge.
Bill’s SDSS team downloaded 350,000 SDSS “fields,” which are long, rectangular strips of the sky photographed by telescopes with the corresponding database data of the names, locations, and distances of the galaxies in each field — a few hundred to a few thousand each. There were several million potential galaxies in there.
So our process, in other sections, of manually cutting out the galaxies from the black of space was not an option here. Since no tools existed, we built our own. Bill’s team created code that would automatically cut out galaxies and tag each of them with the relevant location and distance data from the SDSS database. It took months to get this working right.
We then farmed out among ourselves the process of running this code on the 350,000 SDSS fields. It took several weeks, but in the end — by late 2015 — we had approximately 5.5 million individual photographs of galaxies, each tagged with its location in the sky and distance from Earth. A remarkable achievement in itself.
But as Bill and I looked at them, a very obvious and glaring problem emerged. We had several hundred thousand images of other things we didn’t want. Unfortunately, none were real alien UFOs or giant space monsters, which at least would have been newsworthy. They were stars in our own Milky Way, jet and satellite trails, and other mundane IFOs (identified flying objects). This was a bit of a punch in the stomach — we had not realized how much of this was in SDSS data.
Again we discussed the options, and the only practical one was to go through all 5.5 million photographs and remove the bad apples. It was beyond the capability of computing to write a program that could do it perfectly, or even close, and attempting it would take many months anyway. And we would still have to inspect them manually in the end – software is just not smart enough.
We considered farming the job out to volunteers, but after testing I realized that it was impossible for a number of reasons: the judgment required to decide which items to remove, the speed and capacity of the computers needed to handle folders of tens of thousands of galaxies, the need for very large monitors and controlled lighting conditions to be sure consistent decisions were made – it all meant to have any hope of ending up usable within our means, it would have to be a single person working full-time.
The only practical plan was for me stop everything and do it myself. But given how committed we were, I did not agonize over it too much. It had to be done, or give up in failure. I hoped it would take two to three months. It took six months, with two weeks off in the middle. It was the same thing every hour for every day I worked on it:
Load up a folder of SDSS cutouts. Anywhere from one to 100,000 galaxies, plus garbage, would be in the folder. Build a thumbnail view of folder in Adobe Bridge.
Go through all the thumbnails at a size that corresponded to the largest size they would appear on the giant screen.
Remove the local stars, jet trails, etc., without a good galaxy candidate in them.
Then go back and open photographs with a good galaxy candidate, but also containing a local star or jet trail and trim that out to leave the good galaxy candidate behind.
Backup and do the next folder.
I have to be honest. It’s the hardest thing I ever did in my life. It took intense visual cortex concentration to do it. I could only do it eight hours a day (six during the last month), six days a week (five in the last month).
After the first few weeks, I thought I was losing my mind: I was starting to have really strange stuff in my head from staring at tiny objects all day, listening to music. My arms, wrists, and hands were a wreck. But I realized that by doing such an intense right-brained, repetitive activity, my left brain was losing it. I found I could listen to podcasts and audiobooks without an issue; in fact, it helped tremendously. I bought a gaming mouse with programmable macros, used disability features in the operating system, and cut my mouse clicks by over 80%.
Here’s a short timelapse of typical day cleaning including running backups.