Orbital vs Suborbital Space Tourism
Why are some of our space dreams so suboptimal?
Back in 2012, I wrote a blog post on my space-faring dreams — specifically, a space-walk in a very-low orbit around the moon, with an unfettered view, soaring like superman above the lunar landscape. But, I mainly wrote about why I have no interest in suborbital rocket tourism, especially compared to the alternative experiences out there (zero-g flights and high altitude balloons).
Now in 2020, suborbital tourism has become even less appealing (shorter flights and lower altitudes), and I have to wonder if people are imagining that these suboptimal flights are something that they are not — something akin to the magical experiences astronauts had over the past 50 years.
I was reminded of this when Space Adventures announced their 2021 orbital tourism offerings yesterday, going to the same heights as Gemini XI… 16x higher than the suborbital hoppers. Their photo strip of the views at different altitudes are very different from the photos I have seen from our amateur rockets and balloons. So, I added them below for contrast.
Let’s consider the ostensible selling points for suborbital tourism:
1) VIEWS: If you launch from New Mexico, expect to see the unremarkable desert of New Mexico surrounding the launch site. And maybe some clouds. Not America. Not Earth. Not a dramatic curvature of the Earth (the photos from this altitude that appear to show that are a distortion artifact of wide-angle lenses, like a GoPro camera). Yes, the blackness of space, but not more than what your eye can discern from high-altitude balloon flights or military jet flights available today. And you won’t have much time to reflect and take photos versus the alternatives.
For a sense of the “new perspective” on Earth from 51 miles up, imagine looking out at a 45° angle, like the photo above. You’ll be looking 51 miles out in any direction. That’s it — 51 miles away from the launch site. You can see more looking out to the horizon, but it not that different from high-altitude flight. As you raise your eyes to the horizon, it’s mostly a blur of clouds fading to blue and black.
(addendum: you can calculate the theoretic limit to visibility — the horizon line given Earth's curvature at the record altitude (293K ft.) ever reached by VG (and they claim flights will be lower when they have a full payload of passengers) — and that would just reach Baja. 1.22*√293K = 660 miles. But, look at the views from apogee when the VG folks say this. The clouds obscure all views beyond basically, the local desert. You can't see any features in the distance (and the Baja peninsula is a mighty big feature, so most likely to be visible). At the horizon limit, you are looking through a lot of atmosphere, and maybe they got a blurry peek? The image above in the photo collection is the most cloud-free I have seen)
So, what’s the breathtaking perspective we keep hearing from astronauts? It is magical up there. But that comes from the lateral movement —17,500 MPH around the Earth, in orbit. The point of view difference between an orbital versus suborbital rocket is like the different views from an airplane versus a skyscraper. They call it a suborbital “hop” for a reason. Up and down, like a big trampoline jump.
It’s all about the motion, the experience that is unlike anything else on Earth. The Apollo 11 astronaut, Michael Collins, described his Gemini orbit (250 miles up, same as the ISS) so beautifully in his autobiography, Carrying the Fire:
“This is the best view of the universe that a human has ever had. We are gliding across the world in total silence, with absolute smoothness; a motion of stately grace which makes me feel God-like as I stand erect in my sideways chariot, cruising the night sky.”
“The view is absolutely breathtaking! I will try to explain it. First some arithmetic. At two hundred miles above a sphere whose radius is four thousand, we are just skimming along one twentieth of a radius above the surface. The atmosphere itself is ridiculously thin, thinner than the rind on an orange, and we are just barely above it.”
“Our much higher orbital velocity is balanced out by our higher altitude, so the angular changes (the most important visual cues of speed) are still within the realm of the commonplace. Although the sky is absolute, unrelieved black instead of blue, the colors below look about the same as they would from an airplane.”
“Then what is so impressive, what makes it different? Supertourist is up, and what a feeling of power! Those aren’t counties going by, those are continents; not lakes but oceans!”
“I think nirvana must be at an altitude of 250 miles… I am in the cosmic arena, the place to gain a celestial perspective; it remains only to slow down long enough to capture it, even a teacup will do, to last a lifetime below.”
None of that happens on a suborbital flight.
2) WEIGHTLESSNESS: Having done zero-g flights on a specialized plane, I highly recommend the weightless experience, and those parabolic flights are so much more accessible and affordable today than a suborbital flight. It’s not an extended period of zero-g, but in 30-second episodes (and 60 seconds for lunar and Mars gravity simulation), you can play in weightlessness for a lot longer per dollar spent. For $5K, you can get 12 of those episodes, a longer period of weightless time at a 40x cost advantage to suborbital rockets. To be fair, it is broken up into many pieces, but that gives you time to learn, plan and set up for the next one before it’s all over. There is definitely a learning curve for weightless play time. :)
But the comparison worsens on quality. The available space for movement is much, much greater in the airplane than a suborbital rocket (where the best of them might let you get out of the seat for a bit to bumble about in a small cabin, but you have to get back and buckled in for reentry with plenty of time to spare).
On a zero-g plane, in contrast, you can do “superman” flights over 30 foot stretches. You can build inverted human pyramids or “play ball” tossing someone in the fetal position back and forth. You can do various experiments with spin stabilized bananas or water droplets. We did all that on my first flight.
On a suborbital rocket ride, the zero-g play time trades off with window time. You only have a few minutes for both.
3) BRAGGING RIGHTS: For some, there are other critical factors, so it’s worth acknowledging that, even if they don’t appeal to me personally. Some are thrill seekers, and like being on the cutting edge of dangerous activities. Some are enthralled with the coolness of the technology – a suborbital rocket flight is a better bar story than a parabolic zero-g plane flight. Symbolism and bragging rights can also be uniquely special for some people, like being the first person from a small nation to voyage in space. I see how that can be exciting back in the home country… and being able to say you’re an astronaut, if only for a few minutes. But ironically, all of these factors fade away when the product is safe and routine, both prequisites for any business success. It will be widely understood that you took an overpriced aerospace ride, like a passenger in a plane.
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P.S. In contrast, consider Space Adventures to 840-mile high Gemini orbit:
"The first mission of its kind will attempt to break the altitude record for private citizen spaceflight. Participants will see planet Earth the way no one has since the Gemini program. Up to four private citizens can fly on this mission, which will be the first orbital space tourism experience provided entirely with American technology. The Crew Dragon has been designed to fly completely autonomously, and this means that the training time commitment for participants will be less than for other spaceflight experiences." Promo Video.