Did you know that space research doesn’t all get done in space? In fact, some very cutting-edge science gets done on vehicles that don’t go all the way into orbit. It’s a realm of experimentation that takes place in what’s called “suborbital space”.

Recently, I was privileged to attend the Next-Generation Suborbital Researchers Conference. It gathered together about 300 professionals who enable science far above our planet in that suborbital realm. Their experiments take place at heights that allow them to do microgravity experiments and other projects. For many years, most of these flights were in the domain of space agencies such as NASA. However, the suborbital realm is now open to all, something noted by meeting convener Dr. Alan Stern, as well as in a keynote talk given by NASA Administrator Jim Bridenstine. He focused on the amazing discoveries that will be made by suborbital research communities.

Suborbital Science Has a History

Scientists have used balloons and sounding rockets for decades—since before the dawn of the Space Age. However, today’s generation of researchers is sending experiments (and sometimes themselves) up to do their work. It happens in reusable rockets, more sophisticated balloon-borne vehicles, and Vomit Comet-like flights. They all offer a few seconds of microgravity or take sensors up above Earth’s occluding atmosphere for cutting-edge research. Those scientists, and the companies that help put their work into suborbital space, were attendees at the NSRC meeting. They represent a new generation of scientists and represent the next wave of suborbital rocket and balloon-borne vehicles that are online or will be available very soon.

Getting to Do Suborbital Science

These days, scientists with research experiments have a wide variety of ways to get to sub-orbital space. What they “hire” depends on what they need. There are micro-gravity flights aboard Zero Gravity Corporation’s aircraft (also known as ZERO GEE). It flies fly parabolic arcs that supply multiple opportunities for “weightless” microgravity flight. There are also be flights above the “Kármán” line (62 miles or 100 km) above Earth’s surface. In the near future, some of these will take place aboard Virgin Galactic’s Unity SpaceShip Two system. On each of these flights, scientists can send robotic experiments, or fly along with their equipment for human-tended projects.

Suborbital Science on Rockets

Blue Origin’s New Shepard has lofted more than a hundred payloads for short-term experiments returned to Earth for analysis. As well, companies such as Northrup Grumman are also sending rockets up with research and other types of payloads. So, it seems that suborbital space is a happening place. It’s accessible through these and other companies such as Masten Space Systems (provider of rocket launch systems). There’s also Sugarhouse Aerospace. It plans to launch inexpensive systems in cubes. These and other companies started up recently to provide affordable access to suborbital space.

Balloons Rule Suborbital Science, Too

Let’s not leave out balloon-lofted experiments. They have been done for decades. Various astronomy experiments such as the BLAST instrument (Balloon-borne Large Aperture Submillimeter Telescope) have utilized balloons. However, today, researchers also have access to such craft as Worldview’s Stratollites. Those give long-period access to experiments ranging from earth studies to space observations. They send cameras and other sensors high into the atmosphere for continual studies.

Suborbital Science Results

During the three days of the NSRC meeting, we heard about many different kinds of experiments being done in suborbital space. One that caught my attention was a microgravity experiment conducted by an old colleague from the University of Colorado, Dr. Joshua E. Colwell. He and his team wanted to study the earliest steps of the formation of planetesimals in the solar system. This happens when small-scale objects (pebble-sized and smaller) start to accrete to make larger objects. Eventually, as time passes, they do get larger and larger, and eventually asteroids, and then planets are formed.

The Colwell team experiment is COLLIDE (for Collisions Into Dust Experiment) and PRIME (Physics of Regolith Impacts in Microgravity Experiment). The scientists used orbital and suborbital platforms and on parabolic high-altitude spacecraft, flights to study the impacts of projectiles into a shallow bed of simulated planetary regolith (soil) and low speeds in microgravity. The tests demonstrated that even at low speeds when particles collide, there is what’s called “mass transfer.” That is, the material sticks to the impactor. And, that kind of mass transfer is an important step in the creation of planets. Studying it on suborbital flights that provide microgravity is a fine way to understand a process that took place 4.5 billion years ago in our solar system.

Suborbital Science for All Ages

That’s just one of many experiments we heard about at the meeting. But, suborbital space isn’t limited to university and private industry researchers. Students of all ages are involved, and their experiments answer intriguing questions. For example, a group of second-grade students, working with Dr. Steven Collicott of Purdue University, flew a little “launchbox” aboard a Blue Origin suborbital mission. Their research question was, “Do fireflies light up in space?” (It turns out they do, as they found out from a flight aboard New Shepard on December 12, 2017.) Such low-cost access to space exposes students to research from an early age. In the case of the second-graders, working with Purdue faculty and students was an added treat.

Other suborbital experiments discussed at the conference covered studies of human factors in space, the effects of gravity transitions on plants, space weather effects, and other types of planetary science research. Student experiments gather a lot of attention, as well as commercial research projects. All of them pointed to one thing: the new age of space exploration starts on the surface of our planet and moves up. No longer do people have to wait to get “on-orbit” to do experiments. Rockets, balloons, and aircraft are all here to loft experiments up to the heights.

Launching Suborbital Science from Where?

So, where do all of these experiments launch from? In the U.S., we all know about the launch complexes in Florida and California. They’re used by SpaceX, NASA, the military, and other groups. Those have been the prime spots for many years. But, with the rise of suborbital flight, other launch locations are available. For many years, White Sands Missile Complex in New Mexico has been used. Vandenburgh Base in California is also available for certain flights, as has been launch facilities associated with the Poker Flat Research Range in Alaska. They’re all available.

Near Las Cruces, New Mexico, SpacePort America is hosting Virgin Galactic flights. Zero Gee launches from Florida and Southern California. And, there are spaceports popping up all over the country, including Colorado and Wyoming. There are also ports planned in other states. I suspect that, in very short order, there will be such places across the U.S. They’ll be part of the new “space economy” and built to handle whatever researchers want to loft into space. And, even more in countries around the world will be adding access, as well.

The Future of Suborbital Science

Suborbital flight has a great future. Not only does it allow access to experimental missions fairly quickly and cheaply, but it also expands flight into more areas of research and education. The opportunity for researchers and teachers to fly themselves and/or their experiments aboard rockets, high-altitude aircraft, and balloons is transformative for research and education.

I’m quite excited about the experiments I did hear about at the conference. I plan to focus on some of those “in-depth” in upcoming entries here. This kind of research is as exciting and fulfilling as the much-promised “tourist flights”. And, soon, I hope, access will become possible for nearly anyone with an idea for an experiment. They face an array of choices: send it up as a stand-alone robotic “box” for a short flight? Or, go along for the ride, and do your experiment in microgravity. I know which one I would choose!