Appendix: Powers of 10 Style Universe Tour

Optional Controls
During the tour, some separate optional digital effects may be useful to give a frame of reference to the audience. Note also that at each stop in the tour, the presenter is encouraged to orbit manually to bring up the best view for the audience. The tour should be set up only to move in distance, but not move in any orbital rotation or orbital position. 

The following are your own customised digital effects:

Distance Grids: These allow the user to turn distance grids off and on as they wish. Grids should be turned on by default within the tour sequence. If the scene appears too crowded, the user may wish to turn off grids.Distance grids may need to be resized for your own dome.

Scale Up Galaxy: “Scale Up Local Group” scales up the size of the Local Group galaxies. “Scale Up Tully Galaxies” scales up the size of the Tully survey of galaxies. These are useful to demonstrate that each dot in the data represents an entire galaxy. 

Center Lines: The four Center Line Effects —”Solar System,” “Milky Way,”  “Galactic,” and “Extra Galactic”— incrementally scale up the centerlines for the Solar System, Milky Way, Galactic, and Extra Galactic datasets. These are useful to help point out where home is, especially once the tour has moved far out of the Solar System. Note: the Solar System centerline is actually centered on the Sun, and the tour always stays centered on Earth. 

Home Marker: The “Earth Locator” effect toggles on a blue four-arrow marker attached to Earth. This is useful if the user wishes to remind the audience where Earth and the origin of the tour is on the dome. 

Optional: The “Fly Home” effect is optional, in case the user would like to show a flight home immediately at the end of the tour. The effect assumes the user has run the tour until the end, at 1026 m, and the WMAP survey. Like the “Return Home” digital effect (see the script), the “Fly Home” effect will move the view 10 times the distance closer to Earth every 3 seconds, without any stops, until reaching 10m from Earth. Data will be faded off as we go. 

Tour Narration

Powers of 10 Style: Here we are, 10 million meters away from the center of Earth, where we can see the whole of our planet. On our tour, we will move in increments of “powers of 10” every 10 seconds. That is, when we start to move, we’ll move 10 times the distance in 10 seconds, moving to 100 million meters, then 1000 million (or 1 billion) meters, then 10 billion meters, and so forth. But at each stage, we’ll always stay centered on Earth. Are you ready?

108 Moon: Now we’re 100 million meters from Earth, and from here the Moon’s orbit just fits on the dome. This is as far as any human has traveled—to the Moon.

109At 1 billion meters from Earth, not much changes, except we’re further away, and Earth is a mere dot. 

1010At 10 billion meters, even the Moon’s orbit appears tiny, but we start to just get a sense of our inner Solar System.

1011 Inner Solar System: At 100 billion meters, we can now see the orbits of all the inner planets in the Solar System—Mercury, Venus, Earth, and Mars. 

1012 Outer Solar System: At 1 trillion meters, or about 7 astronomical units (AU, 1 AU being the average distance between Earth and the Sun), we can see the scale of our entire Solar System, with the orbit lines of all the planets and dwarf planets. We’re now beyond where even our furthest robotic space probes have traveled.

1013 1 Light Day: At 10 trillion meters (about 70 AU), we can see just beyond about 1 light-day on the dome—that is, the distance light can travel in a single day at its incredible speed of 300,000 kilometers per second. We can see a grid of concentric circles, the innermost circle denoting 1 light-day from the Sun. We can also see the trajectories of the Pioneer 10 and 11 and the Voyager 1 and 2 probes, mapped out until the year 2050 (approximately 1 light-day away). Notice each probe is traveling orthogonally out of our Solar System. 

1014 1 Light Month: At 100 trillion meters (about 700 AU), we can see out to about 1 light-month—the distance light can travel in 4 weeks. 

1015 1 Light Year: Now we are 1 quadrillion meters from Earth. That’s a 1 followed by 15 zeros! At this distance, we can the dome is filled to about a 1 light-year (ly, the distance light travels in 1 year) radius from Earth, just to the end of the furthest green circle.

1016 10 Light Years: At 1016 meters, the furthest green circle is 10 ly from the Sun. We can now see a red spherical grid, which represents the Oort Cloud. This is where long-period comets come from, and is thought to comprise a shell of icy material, about 1 light-year in radius from the Sun. It’s actually still part of our Solar System, and can be thought of as one boundary of the Solar System, where the Sun’s gravitational dominance ends. We can also see our constellations, still in their familiar shapes. 

1017 Stars: At 1017 m (about 3 parsecs, or 10 ly) from Earth, that’s when the stars start to appear to move, and the constellations are just starting to stretch out of shape. 

1018 1 Kilo Light Year: At 1018 m (30 pc) from Earth, the constellations all seem to point home, demonstrating that the stars in the constellations have a depth to them, and it is only our perspective on Earth that makes them look “flat” against the sky. The blue grid that has appeared is the Radio Sphere, about 100 ly in radius. This is the boundary that shows how far our radio signals have traveled, since we have had the technology to send powerful radio signals out into space (i.e, for about 100 years). These radio signals travel at the speed of light, getting ever-fainter as they move out deeper into space every year. Within the Radio Sphere, as we are now, any extraterrestrials that might exist could, in theory, intercept our signals and infer our existence as an intelligent, technological species. However, outside the Radio Sphere as we are now, any extraterrestrials are physically too far away to have received any radio signals from Earth. Our grid now stretches out to 1000 ly (or 1 kilolight-year) at the dome edge. 

1019 10 Kilo Light Years: At 1019 m (300 pc), we can now see to about 10 kly at the dome’s horizon, and the constellation lines converge towards home. And yet, at this great distance, we are still have not left our galaxy yet. Indeed, every one of the stars we can see with the naked eye in the night sky are within our own galaxy. 

1020 Milky Way: At 1020 m (3 kpc), we now begin to see part of the structure of our own Milky Way Galaxy, just making out its spiral structure noting the bright central bulge. Within the dust of the spiral arms, we note areas of active star formation. 

1021 Local Group: At 1021 m (30 kpc), we have drifted far from our Galaxy to see the entire structure, noting we live around a single star among hundreds of billions about ⅔ of the way from the center to the edge of the Galaxy. We also see that the Milky Way is in fact just one member of the Local Group of galaxies, represented by these green dots. But, bear in mind that each one of these dots represents not a star, but an entire galaxy—each dot representing hundreds of billions of stars. As we move further out, we will see more dots, and each dot will again and again represent a galaxy.

1022 Tully Galaxies: At 1022 m (300 kpc), our grid stretches out to 10 million ly, and we float among the Tully survey of approximately 30,000 galaxies. Galaxies that belong to dense clusters are colored red. Other colors represent other groupings of galaxies, whether clusters or strands of galaxies, based on what structural part of the Universe they belong to. 

1023 100 Mega Light Years: At 1023 m (3 Mpc), our grid now extends to 100 million ly. 

1024 2 Micron All Sky Survey: At 1024 m (30 Mpc), our grid extends to 1 billion ly (or 1 gigalight-year). We now see the 2 Micron All Sky Survey (2MASS) of galaxies. This was an infrared survey of the entire sky, and displays almost 200,000 galaxies surrounding the Milky Way. 

1025 2 Degree Field/Sloan Digital Sky Survey: At 1025 m (300 Mpc), our grid now extends to 20 billion ly (20 Gly) from Earth, and we float among the 2 Degree Field (2df) and the Sloan Digital Sky Survey (SDSS) catalog of galaxies. The 2df catalog contains over 200,000 galaxies, and was taken in strips across the sky. The SDSS was the very first digital survey of the sky, and displays nearly 1 million distant galaxies. 

1026 Wilkinson Microwave Anisotropy Probe: We end our tour at 1026 m (3 Gpc) from Earth, viewing the furthest data available—the Wilkinson Microwave Anisotropy Probe (WMAP). These data represent a baby picture of the Universe, representing some of the oldest light we have ever detected, when the Universe was only a few hundred-thousand years old. The colors we see here are the very slight temperature fluctuations (varying by millionths of a degree) in the cosmic microwave background (CMB)—an echo of the Big Bang itself. The red areas are warmer regions and blue areas are cooler regions in these data. The warmer red regions form the seeds of the large-scale structure of the Universe we see today. Studies of the WMAP data led to the most precise determination for the age of the Universe at 13.75 billion years old. They have also led to the discovery that the Universe is only 4% normal (baryonic) matter, 23% dark matter, and 73% dark energy.