Space travel

Space is – as Star Trek puts it – the “final frontier”. Commercial space tourism is still a tiny market by anyone’s standard, but it has definitely arrived – for those who can afford it.

While very few can go to space, everyone with good eyes can see it for free, and do amateur astronomy from anywhere on Earth’s surface.

Outer Space, or simply Space, is the area that is above the Kármán Line, a line that is drawn at an altitude of 100 km (62 mi). The vast majority of space is empty, as there is on average just 1 atom per cubic meter in space. However, there are some objects, both natural and artificial in space, including planets, moons, stars, space stations and artificial satellites.

Starting from the invention of the telescope in 1610, space travel and rocketry had been theorized. The first rocket is launched in 1926 but it did not cross the Kármán Line (one of the commonly accepted boundaries of “space”), and the first rocket to cross the Kármán Line is the V-2 Rocket launched by Germany in 1944. The first animals to be sent into space is some fruit flies launched in 1947 by the US, and the dog Laika was the first animal to be sent into earth orbit launched in 1957 by the Soviet Union.

Driven to prove their superiority during the Cold War, as well as to gain a strategic advantage, the U.S.A. and the Soviet Union began the “Space Race” during the 1960s. In 1961, the first human, Yuri Gagarin, was sent into space by the Soviet Union and after the Americans managed to put some men into space as well, the USSR put Valentina Tereshkova, the first woman, into space in 1963. In 1969, the American Neil Armstrong became the first person on the Moon. Starting from 1971, the Soviet Union launched the Salyut space stations and they were the first space stations ever. Probes began to explore the solar system also around this point. Space seemed very close; at one point, tickets to the moon and to as-yet-nonexistent space stations were being sold.

After the Space Race ended, a new sense of reality set in. The wild dreams of the 1960s and 70s died, and humanity turned its attention earthward again. Space travel beyond Earth’s orbit became the exclusive domain of mankind’s robotic explorers, and high-profile tragedies both reaching and returning from orbit provided sobering reminders of the risks of space travel. By the end of the 20th century, travel into space was still exclusively the domain of governmental organizations.

However, necessity changed the situation with the dawn of the 21st century, starting with the construction of the International Space Station in 1998. Desperate for funds, the Russian Space Agency began to sell seats on Soyuz launches. Businessman Dennis Tito became the first pay-to-fly space tourist in April 2001, and since then a handful have followed in his footsteps, some of them even on more than one flight.

Space is an extreme environment. The temperature is about −270 °C (−454 °F), cosmic rays would cause fatigue, nausea, vomiting and damage to the immune system, and body fluids, such as blood, boil in space. So a space suit must be worn when outside of ships and space stations.


Spaceflight (or space flight) is ballistic flight into or through outer space. Spaceflight can occur with spacecraft with or without humans on board. Yuri Gagarin of the Soviet Union was the first human to conduct a spaceflight. Examples of human spaceflight include the U.S. Apollo Moon landing and Space Shuttle programs and the Russian Soyuz program, as well as the ongoing International Space Station. Examples of unmanned spaceflight include space probes that leave Earth orbit, as well as satellites in orbit around Earth, such as communications satellites. These operate either by telerobotic control or are fully autonomous.

Spaceflight is used in space exploration, and also in commercial activities like space tourism and satellite telecommunications. Additional non-commercial uses of spaceflight include space observatories, reconnaissance satellites and other Earth observation satellites.

A spaceflight typically begins with a rocket launch, which provides the initial thrust to overcome the force of gravity and propels the spacecraft from the surface of the Earth. Once in space, the motion of a spacecraft – both when unpropelled and when under propulsion – is covered by the area of study called astrodynamics. Some spacecraft remain in space indefinitely, some disintegrate during atmospheric reentry, and others reach a planetary or lunar surface for landing or impact.

The first human spaceflight was Vostok 1 on April 12, 1961, on which cosmonaut Yuri Gagarin of the USSR made one orbit around the Earth. In official Soviet documents, there is no mention of the fact that Gagarin parachuted the final seven miles. Currently, the only spacecraft regularly used for human spaceflight are the Russian Soyuz spacecraft and the Chinese Shenzhou spacecraft. The U.S. Space Shuttle fleet operated from April 1981 until July 2011. SpaceShipOne has conducted two human suborbital spaceflights.

On a sub-orbital spaceflight the spacecraft reaches space and then returns to the atmosphere after following a (primarily) ballistic trajectory. This is usually because of insufficient specific orbital energy, in which case a suborbital flight will last only a few minutes, but it is also possible for an object with enough energy for an orbit to have a trajectory that intersects the Earth’s atmosphere, sometimes after many hours. Pioneer 1 was NASA’s first space probe intended to reach the Moon. A partial failure caused it to instead follow a suborbital trajectory to an altitude of 113,854 kilometers (70,746 mi) before reentering the Earth’s atmosphere 43 hours after launch.

The most generally recognized boundary of space is the Kármán line 100 km above sea level. (NASA alternatively defines an astronaut as someone who has flown more than 50 miles (80 km) above sea level.) It is not generally recognized by the public that the increase in potential energy required to pass the Kármán line is only about 3% of the orbital energy (potential plus kinetic energy) required by the lowest possible Earth orbit (a circular orbit just above the Kármán line.) In other words, it is far easier to reach space than to stay there. On May 17, 2004, Civilian Space eXploration Team launched the GoFast Rocket on a suborbital flight, the first amateur spaceflight. On June 21, 2004, SpaceShipOne was used for the first privately funded human spaceflight.

Point-to-point is a category of sub-orbital spaceflight in which a spacecraft provides rapid transport between two terrestrial locations. Consider a conventional airline route between London and Sydney, a flight that normally lasts over twenty hours. With point-to-point suborbital travel the same route could be traversed in less than one hour. While no company offers this type of transportation today, SpaceX has revealed plans to do so as early as the 2020s using its BFR vehicle. Suborbital spaceflight over an intercontinental distance requires a vehicle velocity that is only a little lower than the velocity required to reach low Earth orbit. If rockets are used, the size of the rocket relative to the payload is similar to an Intercontinental Ballistic Missile (ICBM). Any intercontinental spaceflight has to surmount problems of heating during atmosphere re-entry that are nearly as large as those faced by orbital spaceflight.

A minimal orbital spaceflight requires much higher velocities than a minimal sub-orbital flight, and so it is technologically much more challenging to achieve. To achieve orbital spaceflight, the tangential velocity around the Earth is as important as altitude. In order to perform a stable and lasting flight in space, the spacecraft must reach the minimal orbital speed required for a closed orbit.

Interplanetary travel is travel between planets within a single planetary system. In practice, the use of the term is confined to travel between the planets of our Solar System.

Five spacecraft are currently leaving the Solar System on escape trajectories, Voyager 1, Voyager 2, Pioneer 10, Pioneer 11, and New Horizons. The one farthest from the Sun is Voyager 1, which is more than 100 AU distant and is moving at 3.6 AU per year. In comparison, Proxima Centauri, the closest star other than the Sun, is 267,000 AU distant. It will take Voyager 1 over 74,000 years to reach this distance. Vehicle designs using other techniques, such as nuclear pulse propulsion are likely to be able to reach the nearest star significantly faster. Another possibility that could allow for human interstellar spaceflight is to make use of time dilation, as this would make it possible for passengers in a fast-moving vehicle to travel further into the future while aging very little, in that their great speed slows down the rate of passage of on-board time. However, attaining such high speeds would still require the use of some new, advanced method of propulsion.

Intergalactic travel involves spaceflight between galaxies, and is considered much more technologically demanding than even interstellar travel and, by current engineering terms, is considered science fiction.

Spacecraft are vehicles capable of controlling their trajectory through space.

The first ‘true spacecraft’ is sometimes said to be Apollo Lunar Module, since this was the only manned vehicle to have been designed for, and operated only in space; and is notable for its non aerodynamic shape.

Interplanetary spaceflight
Interplanetary spaceflight or interplanetary travel is travel between planets, usually within a single planetary system. In practice, spaceflights of this type are confined to travel between the planets of the Solar System.

Current achievements
Remotely guided space probes have flown by all of the planets of the Solar System from Mercury to Neptune, with the New Horizons probe having flown by the dwarf planet Pluto and the Dawn spacecraft currently orbiting the dwarf planet Ceres. The most distant spacecrafts, Voyager 1 and Voyager 2 have left the Solar System as of 8 December 2018 while Pioneer 10, Pioneer 11, and New Horizons are on course to leave it.

In general, planetary orbiters and landers return much more detailed and comprehensive information than fly-by missions. Space probes have been placed into orbit around all the five planets known to the ancients: first Mars (Mariner 9, 1971), then Venus (Venera 9, 1975; but landings on Venus and atmospheric probes were performed even earlier), Jupiter (Galileo, 1995), Saturn (Cassini/Huygens, 2004), and most recently Mercury (MESSENGER, March 2011), and have returned data about these bodies and their natural satellites.

The NEAR Shoemaker mission in 2000 orbited the large near-Earth asteroid 433 Eros, and was even successfully landed there, though it had not been designed with this maneuver in mind. The Japanese ion-drive spacecraft Hayabusa in 2005 also orbited the small near-Earth asteroid 25143 Itokawa, landing on it briefly and returning grains of its surface material to Earth. Another powerful ion-drive mission, Dawn, has orbited the large asteroid Vesta (July 2011 – September 2012) and later moved on to the dwarf planet Ceres, arriving in March 2015.

Remotely controlled landers such as Viking, Pathfinder and the two Mars Exploration Rovers have landed on the surface of Mars and several Venera and Vega spacecraft have landed on the surface of Venus. The Huygens probe successfully landed on Saturn’s moon, Titan.

No manned missions have been sent to any planet of the Solar System. NASA’s Apollo program, however, landed twelve people on the Moon and returned them to Earth. The American Vision for Space Exploration, originally introduced by President George W. Bush and put into practice through the Constellation program, had as a long-term goal to eventually send human astronauts to Mars. However, on February 1, 2010, President Barack Obama proposed cancelling the program in Fiscal Year 2011. An earlier project which received some significant planning by NASA included a manned fly-by of Venus in the Manned Venus Flyby mission, but was cancelled when the Apollo Applications Program was terminated due to NASA budget cuts in the late 1960s.

Interstellar travel
Interstellar travel is the term used for crewed or uncrewed travel between stars or planetary systems. Interstellar travel will be much more difficult than interplanetary spaceflight; the distances between the planets in the Solar System are less than 30 astronomical units (AU)—whereas the distances between stars are typically hundreds of thousands of AU, and usually expressed in light-years. Because of the vastness of those distances, interstellar travel would require a high percentage of the speed of light; huge travel time, lasting from decades to millennia or longer.

The speeds required for interstellar travel in a human lifetime far exceed what current methods of spacecraft propulsion can provide. Even with a hypothetically perfectly efficient propulsion system, the kinetic energy corresponding to those speeds is enormous by today’s standards of energy development. Moreover, collisions by the spacecraft with cosmic dust and gas can produce very dangerous effects both to passengers and the spacecraft itself.

A number of strategies have been proposed to deal with these problems, ranging from giant arks that would carry entire societies and ecosystems, to microscopic space probes. Many different spacecraft propulsion systems have been proposed to give spacecraft the required speeds, including nuclear propulsion, beam-powered propulsion, and methods based on speculative physics.

For both crewed and uncrewed interstellar travel, considerable technological and economic challenges need to be met. Even the most optimistic views about interstellar travel see it as only being feasible decades from now. However, in spite of the challenges, if or when interstellar travel is realised, a wide range of scientific benefits is expected.

Most interstellar travel concepts require a developed space logistics system capable of moving millions of tons to a construction / operating location, and most would require gigawatt-scale power for construction or power (such as Star Wisp or Light Sail type concepts). Such a system could grow organically if space-based solar power became a significant component of Earth’s energy mix. Consumer demand for a multi-terawatt system would automatically create the necessary multi-million ton/year logistical system.

Intergalactic travel
Intergalactic travel is hypothetical manned or unmanned travel between galaxies. Due to the enormous distances between our own galaxy the Milky Way and even its closest neighbors—hundreds of thousands to millions of light-years—any such venture would be far more technologically demanding than even interstellar travel. Intergalactic distances are roughly a hundred-thousandfold (five orders of magnitude) greater than their interstellar counterparts.

The technology required to travel between galaxies is far beyond humanity’s present capabilities, and currently only the subject of speculation, hypothesis, and science fiction.

However, theoretically speaking, there is nothing to conclusively indicate that intergalactic travel is impossible. There are several hypothesized methods of carrying out such a journey, and to date several academics have studied intergalactic travel in a serious manner.

There are many languages spoken on the International Space Station, including Japanese, Italian, French, German, Russian, English and occasionally Portuguese. Everyone knows how to speak English, and all signs are written in English and Russian. You might need to learn some Russian, as only Russia provide rockets to the ISS.

Get in
Although physical fitness remains a concern, the main obstacle to reaching space is the depth of your wallet. In increasing order of both cost and distance from the Earth:

On Earth
Even if you never get to go to space yourself, there are quite a few space-related places on Earth. At these museums and launch sites, you can learn about crewed missions and the robotic probes used as a scientific research tool where cost, distance, lack of sufficiently-advanced technology or extreme conditions make human exploration impractical or impossible. Points which are beyond the reach even of probes are typically only accessible to remote observation from afar, such as by astronomy or radio astronomy.

Because there are so many space museums around the Earth, it will be impossible to list them all. Below are the most popular:

Beijing Planetarium (北京天文馆; Běijīngtiānwénguǎn), 138 Xizhimenwai St (西直门外大街138号; Xīzhíménwàidàjiē), Beijing, China (at exit D of the Beijing Zoo station of the subway), ☏ +86 10 6835 2453. Closed M-Tu, 9:30AM-3:30PM W-F, 9:30AM-4:30PM Sa-Su. Adults (aged 18 to 59): ¥10, children aged between 6 and 18: ¥8, children aged below 6 or seniors aged above 60: free, you’ll have to pay more for the movies.
Canada Aviation and Space Museum, 11 Aviation Parkway, Ottawa, Ontario, Canada (located at the tip of Aviation Pkwy, Aviation Pkwy starts from Ontario Highway 417, a.k.a. Queensway), ☏ +1 613-991-3044, fax: +1 613-993-7923, ✉ 9AM-5PM daily. Not to be confused with Canada Air and Space Museum, that’s a whole different museum. The Canada Aviation and Space Museum have 5 exhibitions, of which 3 is about space and not aviation: Life in Orbit: The International Space Station, Canada in Space, and Health in Space: Daring to Explore. Life in Orbit: The International Space Station is about life in the ISS and how the astronauts handle a micro-gravity environment. There’s a model of the ISS that you an climb in! Canada in Space is an overview of Canada’s most notable Space achievements, including a full-scale model of the satellite Alouette-1 and the Disorientation Station, which you can climb in and spin and get dizzy. And finally, Health in Space: Daring to Explore is about the effect of outer space on humans, such as micro-gravity and cosmic radiation. Adults (aged 18 to 59): $15, seniors (aged 60 or over): $13, children aged 3 to 17: $10, children under 3: free.
Johnson Space Center, 1601 NASA Parkway, Houston, Texas, USA (exit out Saturn Lane in NASA Parkway), ☏ +1 281 483-0123, ✉ 10AM-5PM most days, 10AM-6PM or 9AM-6PM some days, there’s more information on the website. Mission Control for Space Shuttle and International Space Station activities, with an adjacent museum. In the museum, there’s the Starship Gallery, which includes the Apollo 17 command module and a touchable moon rock. The International Space Station Gallery has interactive live shows and real ISS artifacts, and the Mission Mars gallery is an interactive exhibit about Mars. Outside, the Independence Plaza has a model of a space shuttle that you’re able to go in. There’s a Rocket park nearby and it’s available for personal tours. Adults (age 12 and up): $29.95, children aged 4 to 11: $24.95, children aged 3 and under: free, seniors: $27.95.
Mars Desert Research Station, 2200 Cow Dung Road, Hanksville, Utah, USA (beside Utah State Route 24 just outside Hanksville), ☏ +1 303 984-9346, ✉ Experience how it would be to live on Mars. The campus includes 6 buildings: the 2-storied round habitat with a diameter of 28 ft (8 m), 2 observatories, the GreenHab (a crop farming lab), the Science Dome (a lab and control center for the entire station) and the RAMM (Repair and Maintenance Module). $750 per week.
Musée de l’Air et de l’Espace (take Line 7 of the Métro to La Courneuve and then take bus line 152 to Musée de l’Air et de l’Espace, it is right beside the Le Bourget airport), ☏ +33 1-49-92-70-00. Oct-Mar: Tu-Su 10:00-17:00; Apr-Sep: Tu-Su 10:00-18:00. This is one of the earliest air and space museums in the world, and it is over 100 years old. There are 12 halls (exhibitions) in the museum, and 1 of them is about space: La conquête spatiale (the space conquest). There are many models of rockets and satellites. Of the 4 activities, the Planetarium and Planète Pilote (Pilot Planet) is space-related. The Planetarium have a large dome-shaped screen with 7039 stars and 20 deep space objects. The Planète Pilote is dedicated to 6 to 12 year olds, but parents and/or educators may enter. It have an Aviation part and a Space part, and it have over 40 interactive activities. Permanent exhibitions: free; activities for adults/under 26: €9/7 for 1 activity, €14/11 for 2, €17/13 for 3, €21/17 for 4. The Paris Museum Pass can be used here.
Smithsonian National Air and Space Museum, 600 Independence Avenue SW, Washington, DC, USA (in the National Mall near Interstate 395, close to the L’Enfant Plaza metrorail stop.), ☏ +1 202 633-2214. 10AM-5:30PM every day. This museum has exhibitions about both aviation and space exploration, and there’s 3 exhibitions about space exploration. The Space Race exhibit, like its name, is about the Space Race and features a model of the Hubble Space Telescope. The Moving Beyond Earth exhibit is about modern space exploration. It includes presentation stages and gigantic drawings of Earth and the ISS on the wall. Finally, the Exploring the Planets exhibit is about the exploration of the Solar System, and it contains models of the Voyager space probes and the Curiosity Mars rover. Admission free, parking $15.
U.S. Space and Rocket Center, 1 Tranquility Base, Huntsville, Alabama, USA (at Exit 15 of Interstate 565), ☏ +1 800 637-7223. 9AM-5PM every day. Features a Saturn V rocket that was never launched and also includes exhibits on the “Space Race”, the programs that led up to the moon visits, and the ISS. There is a planetarium and a National Geographic theater, with 6 different shows available. Outside of the museum are replicas and test units for numerous other space vehicles, including life-size replicas of the space shuttle and a vertical Saturn V. There is also space simulators outside to experience what it would be like if you’re in space. The Spark!Lab contains many design challenges for you to work on, and there’s a Mars Grill, which is a place to eat. Adults (age 13 and up): $25, children aged 5 to 12: $17, children aged 4 and under: free.

Launch sites and labs
Baikonur Cosmodrome (Космодром Байконур), Baikonur, Kazakhstan (go north through Korolev Avenue and turn right at the end of the road), ☏ +7(495)745 72 61, fax: +7(495)232 34 85, ✉ The rocket launch site of Sputnik 1 and Yuri Gagarin in Kazakhstan, and to this day the main Soyuz launch site. Long strictly off-limits, but now open to limited tourism. Several tour companies operate tours to here, including Star City tours and Baikonur Cosmodrome tours. The Baikonur Cosmodrome plus the entire city of Baikonur is off limits unless you get a special permit, which is usually done by getting a tour company to get the permit for you. Star City tours: ~1,687,000 tenge (€3500) for regular tour, ~2,050,000 tenge (€4800) for VIP tour; Baikonur Cosmodrome tours: ~1,153,000 tenge (€2700) for regular tour, ~2,050,000 tenge (€4800) for VIP tour.
Jet Propulsion Laboratory (JPL), 4800 Oak Grove Dr, Pasadena, California, USA (Go north through Oak Grove Drive and turn right at the end of the road), ☏ +1 818 354-9314, ✉ The designers of the Curiosity Mars rover and the Voyager space probes, it gives public lectures monthly. Tours need to be reserved at least 3 weeks ahead, and they are 2-2.5 hours in length. Passport/identification are required to enter the lab. Free.
Kennedy Space Center Visitor Complex, Cape Canaveral, Florida, USA (go east through Florida State Road 528 and turn left at Florida State Road 3), ☏ +1 855 433-4210, toll-free: +1 866 737-5235. Daily 9AM-6PM or 9AM-7PM; rarely 9AM-8PM. This busy tourist attraction offers museums, movies, a rocket garden and bus tours of former shuttle preparation and launch facilities. This is an official federal site — however, the visitor complex is run by contractors for a profit, so prices are comparable to private tourist attractions, not a typical national park. Basic admission (a 1 day pass) includes an excellent bus tour (including the complimentary bus tour of Launch Complex 39 and the Apollo/Saturn V Center), the museums (including the exhibit featuring the Space Shuttle Atlantis), and the IMAX movies. Additional special tours or programs should be booked in advance since they sell out quickly. NOTE: this facility may *sometimes* be closed on launch days! Cape Canaveral also includes the Air Force Space and Missile Museum. 1-day pass: adults (12+) $57, children (3-11) $47. Discounts and other passes available. Parking $10. Complex on Wikipedia
Guiana Space Centre (Centre Spatial Guyanais), Kourou, French Guiana, ☏ +594 37 77 77 (museum and tours), +594 33 44 53 (rocket launches), fax: +594 33 30 66 (museum and tours), +594 33 31 22 (rocket launches), ✉ (museum and tours), (rocket launches). Museum: M-Sa 8AM-6PM. The European Space Agency’s launch site in French Guiana, and there’s a Space Museum nearby. The space museum have 2 floors. It has 7 permanent exhibits and a planetarium. The launch site provide tours twice a day, from 8AM to 11:30AM and from 1PM to 4:30PM, and it must be reserved 48 hours in advance. Children under 8 cannot go on the tour. You can watch rocket launches from a distance of 7km, 15km or 20km. Children under 8 cannot watch rocket launches, and children between 8 and 16 are sometimes not allowed to watch rocket launches. Museum: adults (11+) €7 (€4 on Saturdays), children (3-10) €4 (€2.5 on Saturdays), children under 3 free.
Mojave Spaceport, 1434 Flight Line, Building 58, Mojave, California, USA (turn left to Airport Blvd. at the Mojave-Barstow Highway), ☏ +1 661 824-2433, ✉ Plane Crazy Saturdays are on the third Saturday of each month. The first FAA-certified Spaceport and the home of Scaled Composites’ private spaceflight program. It does not offer tours, but there are Plane Crazy Saturdays which is open to the public, and allows you to see what the spaceport is like.
Columbus Control Centre, Weßling (outside Munich), Germany. Is used to control the Columbus research laboratory of the International Space Station, as well as a ground control centre for the Galileo satellite navigation system. Open to the public depending on mission status.
Star City (Звёздный городок), Moscow Oblast, Russia (In the Zvyozdny Gorodok Urban Okrug of the Moscow Oblast, it’s surrounded by a forest). Cosmonaut training facility northeast of Moscow. This town’s location is kept in secret until the 1990s, even though the news often talk about it. There’s a statue of Yuri Gagarin in town. About 70% of its population of 6 thousand have jobs about space. There are 2 parts: the residental area and the training facility.
Tanegashima Space Center (種子島宇宙センター), Tanegashima, Japan (In the south of Tanegashima, you will see a sign to the center when driving on the Tanegashima main road), ☏ +81 997-26-2111 (launch site), +81 997-26-9244 (space museum), fax: +81 997-26-9245 (space museum). 9AM-5:30PM on July and August, 9AM-5PM on other days, closed on launch days and Dec. 29 to Jan. 1 and Mondays and Tuesdays after a long weekend (space museum). Japan’s main launch site. The Space Museum beside have free exhibits, and tours of the launch site are also free. There are crowded public viewpoints for launch days, but you can watch rocket launches from anywhere outside 3 km (1.9 mi) from the launch site. There’s a model of Kibo, a Japanese part of the ISS that you can go in and the Rocket Launch Theater in the Space Museum. Free (space museum).
Vostochny Cosmodrome (Космодром Восточный, literally Eastern Spaceport), near Zilokovskiy, Amur Oblast, Russia. Functional since 2016, the Vostochny Cosmodrome was built to reduce Russian dependency on the Baikonur site in Kazakhastan, since after the Soviet Union dissolved, the Baikonur Cosmodrome was in a different country. 15 km off the Trans-Siberian Railway, launches are certainly within viewing distance to train passengers, provided the train passes in the right moment. It had not opened to tourism just yet.

While not actual space travel, the weightlessness experienced in orbit can be duplicated (for durations of less than a minute at a time) with a calibrated parabolic aircraft flight, which alternates low g-forces at the heights of its arcs with high g-forces at the bottoms. The parabolic flights are notoriously nausea-inducing, leading to the nickname Vomit Comet, but commercial operators claim that their shorter flights (15 parabolas) are considerably gentler than lengthy research flights (40–80).

Incredible Adventures, 1903 Northgate Blvd, Sarasota, Florida, USA (Go onto Northgate Blvd from US-301 (a.k.a Washington Blvd) and it’s just a few houses until you’re there), ☏ +1 941-346-2603, toll-free: +1-800 644-7382, ✉ This company provides zero-g flights either from Moscow or from Florida. You can customize when do you want to fly in the Florida flights. In the Florida flights, your plane will go from Martian gravity (1/3 Earth gravity) to Lunar gravity (1/6 Earth gravity) and finally to zero-g, and the flight will last for 10~12 maneuvers and each maneuver lasts for 10 seconds. In the Moscow flights, the flight will last for 1.5 to 2 hours but you’ll only get to float for 5 minutes. The plane will depart from the Chkalovsky Airfield for Moscow and St Pete-Clearwater International Airport for Florida. Children under 18 years old are not allowed to go on either flight. $3000 for Florida, unknown for Moscow (determined by the company).
Zero Gravity Corporation, 5275 Arville Street, Suite 116, Las Vegas, Nevada, USA, toll-free: +1-800-937-6480. Flights from Las Vegas (Nevada) and Cape Canaveral (Florida) on a modified Boeing 727 with a large compartment suitable for weightless tumbling, including several brief simulations of freefall, Lunar gravity (1/6 Terran), and Martian gravity (1/3 Terran). US$3,675/person.
Space Travellers International, Wallnerstr. 1A-1010 Vienna, Austria, ☏ +49 2628-7492-832, fax: +49 2628-987419, ✉ Offering flights with Russian Ilyushin 76MDK (Training airplane of the Cosmonauts) departing from Moscow and also zero-g flights in the U.S. with Boeing 727-200. Russian zero-g flight with a 4-day program: €5,800.
MiGFlug, Grüngasse 19, CH-8004 Zurich, Switzerland, ☏ +41 44 500 50 10, ✉ Offering flights with Russian Ilyushin 76MDK (Special training airplane for Cosmonauts) departing from Moscow and also zero-g flights in the U.S. with a Boeing 727-200. Zero-g flight: €3,500/person.

Edge of space
Flights at altitudes of less than 100 km do not qualify as true space flight, but it is possible to see the curvature of the Earth from altitudes as (comparatively) low as 25 km.

Space Travelers International, Wallnerstr. 1A-1010 Vienna, Austria, ☏ +49 2628-7492-832, fax: +49 2628-987419, ✉ Arranges flights on Russian MiG-31 Foxhound jet flights up to 25,000 meters. Estimated price tag: €21,500 per flight included 4-day program in Russia.
MiGFlug, Grüngasse 19, CH-8004 Zurich, Switzerland, ☏ +41 44 500 50 10, ✉ Offering supersonic flights with a Russian MiG-31 Foxhound jet up to 25,000 meters, departing from Russia and supersonic flights with a Russian MiG-29 Fulcrum jet up to 23,000 meters, departing from Russia. Also offers supersonic flights with an English Electric Lightning jet up to 23,000 meters, departing from South Africa. Edge of space stratospheric flight: €16,500/person.

Sub-orbital flight
Sub-orbital flight is defined as flight at altitudes higher than 100 km but at speeds insufficient to achieve orbit. While there are no operators offering sub-orbital flight, the privately funded and built SpaceShipOne in 2004 demonstrated that this is a possible market and the race is on to commercialize it.

Virgin Galactic. Founded by who else but Richard Branson, Virgin Galactic is selling tickets for sub-orbital flights on SpaceShipTwo for US$250,000 a pop. Flights will go up to 110 km and reach speeds of Mach 3, but while total flight time is 2.5 hours, weightlessness will only last for about six minutes. The company has placed an order for five second-generation spaceships from Scaled Composites, the builders of SpaceShipOne. Initial flights will take place from Mojave, California (US), but later flights will move to Spaceport America near Truth or Consequences, New Mexico (US) and Kiruna, Sweden. Departures will first be weekly, and eventually climbing to once or twice daily. Three-day training will be available on site. A successful test flight was performed on 5 April 2018.
Boeing. Boeing announced the CST-100, a sub-orbital plane capable of suborbital flight and 7-passengers capacity in “competitive prices”.

Orbital flight
All that sub-orbital stuff is pretty nifty, but these days no one’s really ready to accept that you were “in space” until you’ve been in orbit around the Earth. There’s no single altitude for this (it depends on your orbital velocity), but due to atmospheric drag it’s only practical above 350 km. Commonly known as Low Earth Orbit, it is the exclusive domain of Russian Soyuz vessels, Chinese Shenzhou craft, and the International Space Station. This itinerary is likely the most expensive in the world.

Space Adventures, 8000 Towers Crescent Drive, Suite 1000, Vienna, Virginia, USA, toll-free: +1-888-85-SPACE (77223), ✉ Space Adventures has organized orbital flights to the International Space Station (ISS), the only fully functioning space station in orbit. Around US$35 million per person will buy you basic training and a launch on a Soyuz vessel from the Russian Cosmodrome at Baikonur to the ISS. Participants must also fulfill certain physical fitness requirements to ensure their and the mission’s safety. The ISS was launched in 1998 and has a Russian half and an American half. It orbits the Earth once every 90 minutes, and 16 sunrises and sunsets can be seen from it every 24 hours. The ISS consists of 14 main modules including 4 labs, a utility hub, an airlock and a life support module.
Private firms SpaceX and Boeing plan to begin transporting astronauts to the International Space Station. Russia’s Soyuz spacecraft had exclusively filled this gap since the 2011 end of the US space shuttle program. NASA plans to allow tourists to stay on the ISS starting in 2020, charging $35,000 per night. The charge for transportation to and from the ISS by Boeing or SpaceX is estimated at $60 million per flight, though as of 2019 these flights have not yet started.

Trans-orbital flight
Human travel beyond Low Earth Orbit has not been done since the cancellation of the U.S. Apollo program by President Nixon in 1972. The only programs actively working to re-establish this capability are governmental in nature. Whilst there have a been a a few speculative commercial proposals for trans orbital tourist flights, nothing has yet been reliably offered to the potential traveller.

SpaceX is planning a pilot tourist flight around the Moon for Japanese billionaire Yusaku Maezawa, who wants to invite a group of artists to come with him. The trip is planned for 2023, but the company has a history of making ambitious plans and then delaying or canceling them, so it remains to be seen whether they’ll stick to the schedule.

Unmanned space craft have traveled around and outside the solar system, like the Voyager probes, but no human has yet travelled to a planet other than Earth. For years there has been talk of sending someone to Mars, but the barriers are formidable – travel time could be anywhere from several months to a couple of years, the environment is cold and inhospitable, the voyager would be subject to an extended period of weightlessness and exposure to radiation, the entire mission must be self-contained and the question of how to bring the astronauts back to Earth at the end of the journey remains unanswered. In the meantime, the robots bring back valuable scientific data which may not yet be obtainable by any other means.

The sight of the Earth from Space is reputed to be incomparable.
At altitudes above the thick atmosphere, the stars cease to “twinkle”.
Sunrise and sunset lose much of their multicolored glory, but take on greater intensity and speed at orbital and even suborbital velocities.
The Northern and Southern Lights can be seen from space.

Freefall (often inaccurately called “zero gravity”) is a phenomenon which, while not unique to Space travel, occurs only momentarily on Earth, such as in thrill rides or high-speed elevators. If you experience freefall and don’t do some aerobatics and float around the craft, you’ve wasted a great deal of money.
Take pictures – what else are you going to do all day? Don’t forget the extra memory cards.
Tourists traveling on otherwise scientific missions may be expected to contribute to them, participating in medical observations at the least.
Extravehicular activity (EVA). Perhaps better known as spacewalking, this involves exiting the spacecraft to float around in space. This is now available as an option at Space Adventures, but there have been no takers yet: this costs US$20 million extra, requires an extra month of training and has additional fitness qualifications.
Space dive. Orbital Outfitters is designing Sub-orbital Space Suit One, a suit to be worn by crew on sub-orbital flights and potentially suitable for “space diving” from 120,000 ft.

Although space food has come a long way in terms of taste and variety in recent decades, the quality and taste is still not up to standards of most connoisseurs of fine cuisine. Your transportation provider may offer some choice in the foods available, but you will be limited by their willingness to indulge you.

The freeze-dried “astronaut ice cream” sometimes sold on Earth as a novelty item is a misnomer; it has never actually been served on any manned space mission (in a zero-gravity environment, the floating crumbs would likely have interfered with the onboard equipment). However, real ice cream has been eaten in space by astronauts aboard Skylab, the Space Shuttle, and the International Space Station.

Contrary to popular belief, Tang was not invented for the US space programme, although NASA did carry it aboard the Apollo missions.

Water tends to be scarce (as it is heavy and must be brought from Earth), so International Space Station machinery recycles water aggressively. Everything from fuel cell water to humidity and waste water is efficiently recovered. According to some reports on the “fluffy newspiece” pages of the internet, astronauts actually prefer the recycled water. Your mileage might vary, but be assured, that chemically and biologically speaking, the recycled water is 100% safe for human consumption.

Bigelow Aerospace. They built the first successful prototype of an inflatable space hotel in 2006-2007. In 2016, a prototype was delivered to the ISS on a SpaceX rocket to undergoing testing, but otherwise it will remain unoccupied. A 10–60 day “live and work visit”, once available, is expected to cost between $26–37 million.

Stay safe
While more mature technology has made it safer than it was in the 1960s, Space remains an inherently dangerous environment to put yourself in. Cosmic radiation, extreme temperatures, micrometeorites, engineering mistakes, high speeds, explosive fuels, space debris, the distance to terra firma, and the lack of atmosphere make any unplanned situation potentially life threatening. Spacecraft launch testing is extremely expensive, so spacecraft don’t and can’t have thousands of flight hours. By the standards of aviation, every space flight is a test flight.

Both start (unless they invent the space elevator any time soon, you are basically sitting on a huge bomb of fuel and hope it doesn’t explode) and reentry (if you hit it in the wrong angle you burn up in or bounce off the atmosphere) have thus far proven to be the biggest danger during a mission. So far only three humans have died in space (as opposed to start and landing), but there have been several close calls such as Apollo 13 or the very first spacewalk. Some of the technological problems and close calls only became known to the public decades after they happened, so there may still be dangers you won’t even know you are facing.

Voyagers should be wary of purchasing space flights on projects that haven’t yet begun. Many ventures are highly speculative; PanAm’s “First Moon Flights” Club issued over 93,000 waiting list spots between 1968-1971 and predicted launch dates for many subsequent commercial expeditions have slipped just as dramatically. If there are complications with the project or the company goes under, you might lose your money and your plans. Just look at the bold predictions of some private space companies that have already proven to be less permanent than a shooting star.

Stay healthy
Astronaut training is physically demanding, so good physical fitness is a good starting point. Similar physical and mental stresses are present in particularly demanding types of military service, piloting fighter aircraft, mountain climbing, Antarctic expeditions and advanced scuba diving such as cave diving. National astronaut programs often require athlete-like physical fitness and experience from these or comparable tasks. There are no hospitals in space and rescue is difficult or impossible, so people with conditions that might require immediate medical treatment are not qualified for space travel.

You need to exercise to stay healthy in zero gravity. Even so, you’ll still lose both bone and muscle mass. While exercise helps diminish the problem somewhat a long stay will still see you weakened and several cosmonauts and astronauts had difficulty getting out of their capsule and onto their own feet upon landing.

Another concern is cosmic radiation. While you are exposed to a certain level of background radiation at all times, it gets higher in certain areas on earth and once you leave the protective layers of the atmosphere. This is already notable on a commercial transatlantic flight at 10,000 m and only gets worse if you go up to the International Space Station (ISS) at 200 to 300 km above the earth’s surface. While the ISS still enjoys some limited protection against radiation, once you go well beyond that height, or even to the moon, there are short term and long term risks associated with radiation that only get worse the longer you stay. Particularly dangerous are solar storms that may give you a year’s worth of radiation in just a couple of hours. Shielding against radiation is also one of the major problems in ever sending humans to Mars, as all known solutions involve huge amounts of extra weight for the space craft or too high a risk to the crew.