I am perhaps the newest member of the Pioneer Air Museum. Born in 1966, I moved to Fairbanks from my native town of Miami, Florida in November of 1997, and for some years I was the volunteer historian for the Poker Flat Research Range, Alaska's "Eglin Air Force Base/Cape San Blas." (This is Florida's lesser-known space launch site--on the Gulf coast in the Florida panhandle--from which suborbital sounding rockets are launched; the PSCA [Pacific Spaceport Complex - Alaska, formerly called the KLC, the Kodiak Launch Complex], an orbital *and* suborbital launch site, is Alaska's "Cape Canaveral.")
Alaska, like Florida, has also been a launch site for another type of space vehicle, and if current plans are carried out, Alaska will soon--again--be a launch site for these vehicles. They are used for carrying scientific and commercial payloads, scientific and commercial rockoon vehicles--suborbital as well as orbital ones--and space tourists, aboard comfortable pressurized gondolas.
Before suborbital rockets (sounding rockets) came into common use, and before satellite launch vehicles and satellites were developed, space research of all sorts--above-atmosphere astronomy (including at wavelengths that our air absorbs), cosmic ray observations (including of the primary cosmic rays that the Earth's atmosphere largely block from detection), solar radiations, upper atmosphere airglow, etc.--was conducted by means of huge, polyethylene plastic film stratospheric balloons. These balloons, developed soon after the end of World War II, were first utilized in 1947 by the U.S. Navy's ONR--Office of Naval Research--in a long-running effort called Project Skyhook; for this reason (and also their large lifting capacity), these balloons are commonly referred to as "Skyhook balloons," or simply "Skyhooks."
They typically float at altitudes of around 100,000 feet (30 kilometers), although large balloons carrying small, lightweight gondolas have reached altitudes of about 35 miles. The USAF (in particular, the AFCRL--Air Force Cambridge Research Laboratory--in Massachusetts, with launches from Holloman AFB, New Mexico and NASA balloon launches from, and/or managed by, NASA's CSBF--Columbia Scientific Balloon Facility--(formerly called the National Scientific Balloon Facility, located in Palestine, Texas (see here, here, and here--this third site mentions NASA CSBF launches from Fairbanks--stratospheric balloon flights have been conducted for several decades.
These balloons--the original zero-pressure, open-necked Skyhook type, the new indefinite-duration superpressure pumpkin type, and the MIR type, (also see here and here)--are frequently used because 1) they are inexpensive, and 2) even the original, open-necked Skyhook type can stay aloft for hours or days.
These balloons were also used in rockoons, stratospheric balloon-lofted-and-launched rocket space vehicles (see here and here and here and here). Rockoons can reach higher altitudes using smaller rockets, because there is almost no aerodynamic drag in the virtual vacuum at the rockets' launch altitude; in fact, one of the first U.S. satellite launching plans called for using a three-stage rockoon. (The first stage--four clustered solid propellant rocket motors--would have boosted the "stack" from 15 miles, the balloon-release altitude, to 20 miles, the second stage motor would have boosted the remaining vehicle to 200 miles, and the third stage would have accelerated itself--and the satellite payload--to orbital velocity, approximately 17,500 mph.) The USAF's Project Farside rockoons were four-stage vehicles that could reach orbital velocity in vertical ascents (adding a small fifth stage to reach the Moon was also studied). They could--if aimed carefully--have injected small satellites into Earth orbit. But such military projects weren't proceeded with because--at least in part--President Eisenhower preferred creating a civilian space agency (NASA) over inter-service rivalry in space research.
While these various stratospheric balloons' float altitudes aren't officially in space (62 miles, the Kármán line, is commonly accepted as the "border of space"), these balloons are, for all practical purposes, in space, at an altitude of 100,000 feet. At that altitude the sky above is black, the curvature of the Earth is obvious, a barometer--unless it's a special, highly-sensitive one--reads 0 psi, and the human body (including the lungs and the blood) reacts exactly as it would if one were far out in space.
An excellent reference on these huge, high-flying balloons is Luis Eduardo Pacheco's "StratoCat" website. Quite a few were launched from Eielson Air Force Base and Fort Wainwright here in Alaska, most recently from Fort Wainwright in 1998. These balloons have volumes of many millions of cubic feet, and payload capacities ranging from hundreds of pounds to several tons, depending on their sizes and planned mission durations (from hours to weeks). The two linked-to articles below describe and show these balloons' performance parameters:
Introduction to the Special Issue on Scientific Balloon Capabilities and Instrumentation by J.A. Gaskin, I.S. Smith, and W.V. Jones, NASA CSBF
Stratospheric Balloons: Science and Commerce at the Edge of Space by Manfred "Dutch" von Ehrenfried (a stratospheric balloons primer)
In the 1920s and 1930s, there were competitive manned stratospheric flights, between U.S. armed services branches, and between several nations, including the U.S. and the U.S.S.R., which were mirrored by the Space Race of the 1940s - 1970s. Before and even after--until mid-1966--rockets and spaceships were developed, manned edge-of-space stratospheric balloon flights, using the vastly improved plastic film balloons, continued. (Unmanned, instrumented Skyhook balloons have been in continuous use, around the world and by many nations, since 1947.) Luis Pacheco's StratoCat website covers all of these balloon flights in detail. Looking to future balloon operations of these kinds (including from Alaska), rockoon vehicles and space tourist balloons are under active development.
CNBC's Travel section contains an article--with company website links--titled "Want to travel to space? In 2024, balloons might take you part of the way there." CNN's Travel section has also covered this part of the space tourism market.
Fortune magazine has written about Space Perspective, a Cape Canaveral, Florida-based space tourism firm that plans, in concert with Alaska Aerospace Corporation, to fly passenger-carrying, near-space Skyhook balloons from Kodiak Island, Alaska.
Below are listed the website and articles for several--but by no means all--of these new space companies:
Near-Space Balloon Tourism and Rockoon Space Launch Companies: