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Selketalbahn 99 6001-4 climbs away from Stiege working the 14:47 Gernrode to Hasselfelde service on 9th March 2008. The Eisfelder Talmühle–Hasselfelde and Herzogschacht–Lindenberg (now Straßberg) sections of the Selke Valley Railway were dismantled in 1946 and all locomotives and rolling stock were seized by the Soviet Union as war reparations. It was not until late 1983 when the reconstruction of the Straßberg–Stiege section of the Selketalbahn was completed, primarily for providing a direct rail connection for the transport of lignite from Nordhausen to a new cogeneration power plant installed at Silberhütte. Passenger services were resumed in June 1984, and at that time the three Harz narrow gauge lines were reconnected as one network totalling 140 kilometres. The small balloon loop outside Stiege station, part of it visible to the left of this image, was constructed specifically to allow heavy trains from Nordhausen to gain access to the power plant at Silberhütte without the need to reverse at Stiege, as indeed any interconnecting locomotive-hauled services between the Selketalbahn and Harzquerbahn are able to use for the same reason, providing a remarkable network of railway lines in such a small town.
© Gordon Edgar - All rights reserved. Please do not use my images without my explicit permission
One of many concrete bunkers at the Midewin Tallgrass Prairie. Once used to store explosives for the U.S. military, they are now just an interesting part of the landscape.
"The line_up is a paperwork series I developed since 2010. The“liners” are made out of paper (Din A3),
oil paint and graphite, the theme is the hermetical laws of polarity and movement. There is no ending and no beginning in any direction, just an endless movement. You have the possibility to arrange the papers like you want and that makes it an endless playground for my photo-work and the eyes of the viewers."
Yanomano
Malbon opened with the Selwyn line in 1910 as a wayside station to Friezland/Kuridala, having a loop siding and shelter, but from August 1911 it became the junction for a trunk line extension south to Duchess and ultimately to Mount Isa. Facilities from 1912 comprised a goods loop and shed on the left and beyond this was a low-level passenger platform and station office with signal levers nearby. The No. 2 and No. 3 roads for crosses and shunting purposes were sited on the right. The lines to Friezland/Kuridala and Duchess cursed away from each other at the south end and the two were joined by a third to form and angle. Signals protected the station at each end. A watering facility and ashpit was built at the other end of the yard.
Malbon pre-dated the railway as a gold mining settlement from the 1870s and remained intact with its hotels, stores, school, and post office by the time the railway arrived. The railway gave the town a fillip as a supplier of firewood and copper ore. Malbon was a busy station from 1912 to 1921 when it handled all the trains to and from Cloncurry, Duchess, Ballara, and Trekelano. Several of these services required remarshalling or running around the angle to get to Kuridala or Selwyn. The Selwyn branch services used Malbon either as a through stop to Cloncurry to Duchess or as a turn around point. An average weekday at the copper boom peak from 1916 to 1918 saw around a dozen trains arrive at and depart from the station between 04:20am to 11:45pm.
The station was staffed by a Station Master and this position remained until 1935 when the place was downgraded to a Gate. A Station Mistress worked day shift and a Night Office at night for crosses. The place was home station to fettling gangs and around eight departmental residences were provided here for these workers and the station staff.
The Station Master position was reinstated in late 1943 due to increases in wartime traffic and this office lasted until 1972, after which a Station Mistress was appointed. The station was de-staffed shortly before Train Order Working was introduced in July 1988.
Facilities mirrored the traffic levels. A station office and shelter was provided from the beginning. The station office burnt down in 1947 but was replaced and this building continued in use until 1989 when it was sold for removal. A goods shed was provided and saw sufficient use to the war years. It was removed in 1947 but the closure of the Selwyn line in 1961 made Malbon a railhead so another shed was provided in 1962. It remained in service until 1989 when it was sold for removal. A refreshment room opened in 1917 and it traded until 1954.
Passenger traffic was vigorous from 1912 to 1919 and then fell from nearly 6000 annual journey to a few hundreds. Traffic improved during the Second World War and increased in the early 1960s on account of the workers on the Mount Isa Line rehabilitation project but again fell away and dipped to virtually nothing after 1973.
There was traffic in firewood and mining timbers in the period of 1912 to 1919 and small amounts of firewood to the late 1940s. Cattle loadings were at around 5000 head per year until declining from the mid 1960s to a handful by the 1980s. The closure of the Selwyn line in 1961 generated no additional on-forwarding cattle traffic to Malbon although wool loadings made and appearance for the first time. The wool traffic was at reasonable levels until 1967 and then dipped to insignificance.
Mineral ores were loaded in major quantities from 1911 to 1914 and lesser amounts to 1921 when they dwindled to negligible amounts for decades. A mining revival from the 1960s at sites along the then closed Selwyn railway saw Malbon used as the rail loading point for these ores. A dead end ore siding and loading ramp was built at the time. The ore traffic predominated from 1962 to 1968, 1974 to 1975 and 1988 to 1989. Peak loadings were in 1967 and 1968 when a total of 183 000 tons were despatched from the Young Australia mine at Kuridala. Five trains a week were required to move this ore to Mount Isa. New generation mines and processors in the 1980s resulted in a traffic of copper concentrate from Selwyn mine to Townsville that was loaded in tens of thousands of tons annually from 1988 to 1991. A second ore spur road with a large loading ramp was installed for this mineral traffic.
Independent of local traffic, Malbon was a prime load shedding station for the Mount Isa to Cloncurry trains in the steam days, particularly from the late 1940s. Down trains from Mount Isa could drop excess tonnage (555 down to 450 tons) for the heavier grades towards Cloncurry and this was later picked up by an engine and van sent from Cloncurry. This arrangement ensured trains to the maximum loads were run out of Mount Isa. There was ample capacity at Malbon to store wagons and cross trains simultaneously using the existing sidings and the Selwyn line lead in.
The Malbon station yard was rationalised in the 1990s when Direct Traffic Control was introduced and all buildings and roads removed except for the passing loop and on dead end siding (along the route of the former Selwyn line). The last of the departmental residences were removed, although a little while later one was returned for operational reasons and remains at the time of writing (2008).
In a photograph captured in 1920, the main street of Malbon consisted of three hotels; these being the Malbon Hotel, the Railway Hotel, and Doherty’s Bar. The last of these licensed establishments, the Malbon Hotel, burnt down in the 1970s. The old Malbon railway station was relocated to a house block after 1989.
The Malbon township survived in part until the 1970s when the last remaining hotel burnt down and the railway houses were vacated and removed. At the time of writing (2008) the place has shrunk to one street with three or four houses (including the former station building) plus a public telephone to contact the Selwyn mine.
Source: Copper at the Curry by Norman Houghton.
Upon discovering the date of the First Cumbrian Mountain Express railtour with RTC over the famous Settle and Carlisle line, I took a visit to Hellifield station to watch said railtour and for refreshments in the Cafe on the station.
Sadly after the railtour left, there was a trespassing incident with two idiots having gone down the platform near the tracks to take photographs. This didn't affect the railtour thankfully.
Photo copyright: Georgie Read
Modern cars can do over 100,000 miles without pausing for breath. If you really pile on the miles, you might have 200,000 or even 300,000 miles on the clock. If the car Gods are really shining on you, you might have managed more than half a million.
Prepare to feel insignificant. Irv Gordon from East Patchogue, New York, together with his Volvo P1800, a 1966 1800S, has completed over three million miles--a new world record for the highest number of miles driven by a single person in the same car. If you're after an arbitrary comparison to offer some perspective, that's around six round-trips to the moon, or 120 circumnavigations of Earth.
Gordon hit the three million miles mark on September 18 while driving near the village of Girdwood, on the Seward Highway, south of Anchorage, Alaska; one of the two remaining states where Irv and his famous car had not been together until now.
”It was all rather undramatic,” said Irv. ”We just cruised along and I kept an eye on the odometer in order not to miss the great moment”.
Gordon first bought his 1800S on a Friday back in 1966 and immediately fell in love. He simply couldn't stop driving the car and over the course of the weekend he had already covered 1,500 miles, causing him to return to the dealership he bought it the following Monday in order for its first service.
With a 125-mile round-trip daily commute, a fanatical dedication to vehicle maintenance and a passion for driving, Gordon logged 500,000 miles in 10 years. In 1987, he celebrated his one-millionth mile by driving a loop around the Tavern on the Green in Central Park, and in 2002 he drove the car's two-millionth mile down Times Square. Since then, Gordon has broken his record every time he gets behind the wheel of his beloved Volvo.
[Text from MotorAuthority]
www.motorauthority.com/news/1087353_irv-gordon-reaches-3-...
History
The project was started in 1957 because Volvo wanted a sports car, despite the fact that their previous attempt, the P1900, had been a disaster, with only 68 cars sold. The man behind the project was an engineering consultant to Volvo, Helmer Petterson, who in the 1940s was responsible for the Volvo PV444. The design work was done by Helmer's son Pelle Petterson, who worked at Pietro Frua at that time. Volvo insisted it was an Italian design by Frua and only officially recognized that Pelle Petterson designed it in 2009. The Italian Carrozzeria Pietro Frua design firm (then a recently acquired subsidiary of Ghia) built the first three prototypes between September 1957 and early 1958, later designated by Volvo in September 1958: P958-X1, P958-X2 and P958-X3 (P:Project 9:September 58:Year 1958 = P958).
In December 1957 Helmer Petterson drove X1, (the first hand-built P1800 prototype) to Osnabrück, West Germany, headquarters of Karmann. Petterson hoped that Karmann would be able to take on the tooling and building of the P1800. Karmann's engineers had already been preparing working drawings from the wooden styling buck at Frua. Petterson and Volvo chief engineer Thor Berthelius met there, tested the car and discussed the construction with Karmann. They were ready to build it and this meant that the first cars could hit the market as early as December 1958. But in February, Karmann's most important customer, Volkswagen VAG, forbade Karmann to take on the job.[citation needed] They feared that the P1800 would compete with the sales of their own cars, and threatened to cancel all their contracts with Karmann if they took on this car. This setback almost caused the project to be abandoned.
Other German firms, NSU, Drautz and Hanomag, were contacted but none was chosen because Volvo did not believe they met Volvo's manufacturing quality-control standards.
It began to appear that Volvo might never produce the P1800. This motivated Helmer Petterson to obtain financial backing from two financial firms with the intention of buying the components directly from Volvo and marketing the car himself. At this point Volvo had made no mention of the P1800 and the factory would not comment. Then a press release surfaced with a photo of the car, putting Volvo in a position where they had to acknowledge its existence. These events influenced the company to renew its efforts: the car was presented to the public for the first time at the Brussels Motor Show in January 1960 and Volvo turned to Jensen Motors, whose production lines were under-utilised, and they agreed a contract for 10,000 cars. The Linwood, Scotland, body plant of manufacturer Pressed Steel was in turn sub-contracted by Jensen to create the unibody shells, which were then taken by rail to be assembled at Jensen in West Bromwich, England. In September 1960, the first production P1800 (for the 1961 model year) left Jensen for an eager public.
P1800
The engine was the B18 (B for the Swedish word for gasoline: Bensin; 18 for 1800 cc displacement) with dual SU carburettors, producing 100 hp (75 kW). This variant (named B18B) had a higher compression ratio than the slightly less powerful twin-carb B18D used in the contemporary Amazon 122S, as well as a different camshaft. The 'new' B18 was actually developed from the existing B36 V8 engine used in Volvo trucks at the time. This cut production costs, as well as furnishing the P1800 with a strong engine boasting five main crankshaft bearings. The B18 was matched with the new and more robust M40 manual gearbox through 1963. From 1963 to 1972 the M41 gearbox with electrically actuated overdrive was a popular option. Two overdrive types were used, the D-Type through 1969, and the J-type through 1973. The J-type had a slightly shorter ratio of 0.797:1 as opposed to 0.756:1 for the D-type. The overdrive effectively gave the 1800 series a fifth gear, for improved fuel efficiency and decreased drivetrain wear. Cars without overdrive had a numerically lower-ratio differential, which had the interesting effect of giving them a somewhat higher top speed (just under 120 mph (193 km/h)) than the more popular overdrive models. This was because the non-overdrive cars could reach the engine's redline in top gear, while the overdrive-equipped cars could not, giving them a top speed of roughly 110 mph (177 km/h).
1800S
As time progressed, Jensen had problems with quality control, so the contract was ended early at 6,000 cars. In 1963 production was moved to Volvo's Lundby Plant in Gothenburg and the car's name was changed to 1800S (S standing for Sverige, or in English : Sweden). The engine was improved with an additional 8 hp (6 kW). In 1966 the four-cylinder engine was updated to 115 hp (86 kW). Top speed was 175 km/h (109 mph).[3] In 1969 the B18 engine was replaced with the 2-litre B20B variant of the B20 giving 118 bhp (89 kW), though it kept the designation 1800S.
[Text from Wikipedia]
This Lego miniland-scale Volvo P1800 Coupe has been created for Flickr LUGNut's 88th Build Challenge, - "Let's Break Some Records", - a challenge focused on creating vehicles that set some benchmark for biggness, fastness or other extreme of some specification. The Volvo model shown here claim, by far, the farthermost distance ever traveled by an automobile, at over 3,000,000 miles (4,800,00 kilometres).
This is a circuit that will cause the Radio Shack 9V Recording Module (part number: 276-1323) to loop.
Basically when the circuit is turned on by S1, the transistor turns the relay on. When the relay turns on, it causes the two button pins to make contact, which turns on the playing mechanism of the recording module. The transistor then reads the speaker, and when it detects power, cuts off power to the relay. As soon as the sound stops, the transistor then re-engages the relay, starting the sound, cutting off the relay.....continues indefinitely.
A solid state relay would cut down on the noise, but I didn't have one on hand, I had this one, and it works really well due to it's low activating current. You also can't hear the relay in the audio output, which is all I care about.
I used this for a circuit bent guitar I made. I wanted to have some sort of looping mechanism, but wasn't willing to pay $45. This solution cost about $12, and gives 20 seconds of decent sound. The guitar doesn't make a quality sound, so the quality of the recorded sound wasn't as important. I got the idea from a light sensor that would turn on when the light goes out.
8170 races through the now defunct Tullamarine loop as it nears the end of its journey from Sydney. 27th February, 1995.
VR_BOX105S27
The Cygnus Loop (aka Veil Nebula Complex) is a vast supernova remnant about 3 degrees across. The initial explosion released shock waves of gas expanding out at such high velocity that friction with the interstellar medium causes the gases to ionise.
Image is a 2-part mosaic, mapping Ha,OIII,OIII to R,G,B. View at the largest image size to see the more detailed filament structures.
Equipment used: W.O. Megrez 72 aporefractor & Flat6 0.8x FR/FF, Astrodon 5nm Ha/3nm OIII filters, QSI 683wsg CCD piggybacked on 8" LX90, autoguided via QSI 683's integrated OAG, SX Lodestar guide camera & PhD. Total exposure time: 15 hours over several nights. Subframes 1200s, unbinned.
Having a break from its usual Citylink 58 route yet still serving Heworth as Citylink would terminate before heading back to Newcastle seen here in Heworth making an odd appearance on Loop Service 94 to Gateshead
© All rights reserved. Images are copyrighted to myself. Photographs lifted from my photostream and being reused elsewhere without my permission or being credited, will not be tolerated and the user will be blocked and reported immediately
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.
History
Main articles: History of spaceflight and Timeline of spaceflight
Tsiolkovsky, early space theorist
The first theoretical proposal of space travel using rockets was published by Scottish astronomer and mathematician William Leitch, in an 1861 essay "A Journey Through Space".[1] More well-known (though not widely outside Russia) is Konstantin Tsiolkovsky's work, "Исследование мировых пространств реактивными приборами" (The Exploration of Cosmic Space by Means of Reaction Devices), published in 1903.
Spaceflight became an engineering possibility with the work of Robert H. Goddard's publication in 1919 of his paper A Method of Reaching Extreme Altitudes. His application of the de Laval nozzle to liquid fuel rockets improved efficiency enough for interplanetary travel to become possible. He also proved in the laboratory that rockets would work in the vacuum of space;[specify] nonetheless, his work was not taken seriously by the public. His attempt to secure an Army contract for a rocket-propelled weapon in the first World War was defeated by the November 11, 1918 armistice with Germany. Working with private financial support, he was the first to launch a liquid-fueled rocket in 1926. Goddard's paper was highly influential on Hermann Oberth, who in turn influenced Wernher von Braun. Von Braun became the first to produce modern rockets as guided weapons, employed by Adolf Hitler. Von Braun's V-2 was the first rocket to reach space, at an altitude of 189 kilometers (102 nautical miles) on a June 1944 test flight.[2]
Tsiolkovsky's rocketry work was not fully appreciated in his lifetime, but he influenced Sergey Korolev, who became the Soviet Union's chief rocket designer under Joseph Stalin, to develop intercontinental ballistic missiles to carry nuclear weapons as a counter measure to United States bomber planes. Derivatives of Korolev's R-7 Semyorka missiles were used to launch the world's first artificial Earth satellite, Sputnik 1, on October 4, 1957, and later the first human to orbit the Earth, Yuri Gagarin in Vostok 1, on April 12, 1961.[3]
At the end of World War II, von Braun and most of his rocket team surrendered to the United States, and were expatriated to work on American missiles at what became the Army Ballistic Missile Agency. This work on missiles such as Juno I and Atlas enabled launch of the first US satellite Explorer 1 on February 1, 1958, and the first American in orbit, John Glenn in Friendship 7 on February 20, 1962. As director of the Marshall Space Flight Center, Von Braun oversaw development of a larger class of rocket called Saturn, which allowed the US to send the first two humans, Neil Armstrong and Buzz Aldrin, to the Moon and back on Apollo 11 in July 1969. Over the same period, the Soviet Union secretly tried but failed to develop the N1 rocket to give them the capability to land one person on the Moon.
Phases
Launch
Main article: Rocket launch
See also: List of space launch system designs
Rockets are the only means currently capable of reaching orbit or beyond. Other non-rocket spacelaunch technologies have yet to be built, or remain short of orbital speeds. A rocket launch for a spaceflight usually starts from a spaceport (cosmodrome), which may be equipped with launch complexes and launch pads for vertical rocket launches, and runways for takeoff and landing of carrier airplanes and winged spacecraft. Spaceports are situated well away from human habitation for noise and safety reasons. ICBMs have various special launching facilities.
A launch is often restricted to certain launch windows. These windows depend upon the position of celestial bodies and orbits relative to the launch site. The biggest influence is often the rotation of the Earth itself. Once launched, orbits are normally located within relatively constant flat planes at a fixed angle to the axis of the Earth, and the Earth rotates within this orbit.
A launch pad is a fixed structure designed to dispatch airborne vehicles. It generally consists of a launch tower and flame trench. It is surrounded by equipment used to erect, fuel, and maintain launch vehicles. Before launch, the rocket can weigh many hundreds of tonnes. The Space Shuttle Columbia, on STS-1, weighed 2,030 tonnes (4,480,000 lb) at take off.
Reaching space
The most commonly used definition of outer space is everything beyond the Kármán line, which is 100 kilometers (62 mi) above the Earth's surface. The United States sometimes defines outer space as everything beyond 50 miles (80 km) in altitude.
Rockets are the only currently practical means of reaching space. Conventional airplane engines cannot reach space due to the lack of oxygen. Rocket engines expel propellant to provide forward thrust that generates enough delta-v (change in velocity) to reach orbit.
For manned launch systems launch escape systems are frequently fitted to allow astronauts to escape in the case of emergency.
Alternatives
Main article: Non-rocket spacelaunch
Many ways to reach space other than rockets have been proposed. Ideas such as the space elevator, and momentum exchange tethers like rotovators or skyhooks require new materials much stronger than any currently known. Electromagnetic launchers such as launch loops might be feasible with current technology. Other ideas include rocket assisted aircraft/spaceplanes such as Reaction Engines Skylon (currently in early stage development), scramjet powered spaceplanes, and RBCC powered spaceplanes. Gun launch has been proposed for cargo.
Leaving orbit
This section possibly contains original research. Relevant discussion may be found on Talk:Spaceflight. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (June 2018) (Learn how and when to remove this template message)
Main articles: Escape velocity and Parking orbit
Launched in 1959, Luna 1 was the first known man-made object to achieve escape velocity from the Earth.[4] (replica pictured)
Achieving a closed orbit is not essential to lunar and interplanetary voyages. Early Russian space vehicles successfully achieved very high altitudes without going into orbit. NASA considered launching Apollo missions directly into lunar trajectories but adopted the strategy of first entering a temporary parking orbit and then performing a separate burn several orbits later onto a lunar trajectory. This costs additional propellant because the parking orbit perigee must be high enough to prevent reentry while direct injection can have an arbitrarily low perigee because it will never be reached.
However, the parking orbit approach greatly simplified Apollo mission planning in several important ways. It substantially widened the allowable launch windows, increasing the chance of a successful launch despite minor technical problems during the countdown. The parking orbit was a stable "mission plateau" that gave the crew and controllers several hours to thoroughly check out the spacecraft after the stresses of launch before committing it to a long lunar flight; the crew could quickly return to Earth, if necessary, or an alternate Earth-orbital mission could be conducted. The parking orbit also enabled translunar trajectories that avoided the densest parts of the Van Allen radiation belts.
Apollo missions minimized the performance penalty of the parking orbit by keeping its altitude as low as possible. For example, Apollo 15 used an unusually low parking orbit (even for Apollo) of 92.5 nmi by 91.5 nmi (171 km by 169 km) where there was significant atmospheric drag. But it was partially overcome by continuous venting of hydrogen from the third stage of the Saturn V, and was in any event tolerable for the short stay.
Robotic missions do not require an abort capability or radiation minimization, and because modern launchers routinely meet "instantaneous" launch windows, space probes to the Moon and other planets generally use direct injection to maximize performance. Although some might coast briefly during the launch sequence, they do not complete one or more full parking orbits before the burn that injects them onto an Earth escape trajectory.
Note that the escape velocity from a celestial body decreases with altitude above that body. However, it is more fuel-efficient for a craft to burn its fuel as close to the ground as possible; see Oberth effect and reference.[5] This is another way to explain the performance penalty associated with establishing the safe perigee of a parking orbit.
Plans for future crewed interplanetary spaceflight missions often include final vehicle assembly in Earth orbit, such as NASA's Project Orion and Russia's Kliper/Parom tandem.
Astrodynamics
Main article: Orbital mechanics
Astrodynamics is the study of spacecraft trajectories, particularly as they relate to gravitational and propulsion effects. Astrodynamics allows for a spacecraft to arrive at its destination at the correct time without excessive propellant use. An orbital maneuvering system may be needed to maintain or change orbits.
Non-rocket orbital propulsion methods include solar sails, magnetic sails, plasma-bubble magnetic systems, and using gravitational slingshot effects.
Ionized gas trail from Shuttle reentry
Recovery of Discoverer 14 return capsule by a C-119 airplane
Transfer energy
The term "transfer energy" means the total amount of energy imparted by a rocket stage to its payload. This can be the energy imparted by a first stage of a launch vehicle to an upper stage plus payload, or by an upper stage or spacecraft kick motor to a spacecraft.[6][7]
Reentry
Main article: Atmospheric reentry
Vehicles in orbit have large amounts of kinetic energy. This energy must be discarded if the vehicle is to land safely without vaporizing in the atmosphere. Typically this process requires special methods to protect against aerodynamic heating. The theory behind reentry was developed by Harry Julian Allen. Based on this theory, reentry vehicles present blunt shapes to the atmosphere for reentry. Blunt shapes mean that less than 1% of the kinetic energy ends up as heat that reaches the vehicle, and the remainder heats up the atmosphere.
Landing
The Mercury, Gemini, and Apollo capsules all splashed down in the sea. These capsules were designed to land at relatively low speeds with the help of a parachute. Russian capsules for Soyuz make use of a big parachute and braking rockets to touch down on land. The Space Shuttle glided to a touchdown like a plane.
Recovery
After a successful landing the spacecraft, its occupants and cargo can be recovered. In some cases, recovery has occurred before landing: while a spacecraft is still descending on its parachute, it can be snagged by a specially designed aircraft. This mid-air retrieval technique was used to recover the film canisters from the Corona spy satellites.
Types
Uncrewed
See also: Uncrewed spacecraft and robotic spacecraft
Sojourner takes its Alpha particle X-ray spectrometer measurement of Yogi Rock on Mars
The MESSENGER spacecraft at Mercury (artist's interpretation)
Uncrewed spaceflight (or unmanned) is all spaceflight activity without a necessary human presence in space. This includes all space probes, satellites and robotic spacecraft and missions. Uncrewed spaceflight is the opposite of manned spaceflight, which is usually called human spaceflight. Subcategories of uncrewed spaceflight are "robotic spacecraft" (objects) and "robotic space missions" (activities). A robotic spacecraft is an uncrewed spacecraft with no humans on board, that is usually under telerobotic control. A robotic spacecraft designed to make scientific research measurements is often called a space probe.
Uncrewed space missions use remote-controlled spacecraft. The first uncrewed space mission was Sputnik I, launched October 4, 1957 to orbit the Earth. Space missions where other animals but no humans are on-board are considered uncrewed missions.
Benefits
Many space missions are more suited to telerobotic rather than crewed operation, due to lower cost and lower risk factors. In addition, some planetary destinations such as Venus or the vicinity of Jupiter are too hostile for human survival, given current technology. Outer planets such as Saturn, Uranus, and Neptune are too distant to reach with current crewed spaceflight technology, so telerobotic probes are the only way to explore them. Telerobotics also allows exploration of regions that are vulnerable to contamination by Earth micro-organisms since spacecraft can be sterilized. Humans can not be sterilized in the same way as a spaceship, as they coexist with numerous micro-organisms, and these micro-organisms are also hard to contain within a spaceship or spacesuit.
Telepresence
Telerobotics becomes telepresence when the time delay is short enough to permit control of the spacecraft in close to real time by humans. Even the two seconds light speed delay for the Moon is too far away for telepresence exploration from Earth. The L1 and L2 positions permit 400-millisecond round trip delays, which is just close enough for telepresence operation. Telepresence has also been suggested as a way to repair satellites in Earth orbit from Earth. The Exploration Telerobotics Symposium in 2012 explored this and other topics.[8]
Human
Main article: Human spaceflight
ISS crew member stores samples
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.[9] 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.
Sub-orbital
Main article: Sub-orbital spaceflight
The International Space Station in Earth orbit after a visit from the crew of STS-119
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
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.[10] 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.[11] 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.[12] 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.
Orbital
Main article: Orbital spaceflight
Apollo 6 heads into orbit
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
Main article: Interplanetary spaceflight
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.
Interstellar
Main article: Interstellar travel
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.[13] 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
Main article: Intergalactic travel
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
Main article: Spacecraft
An Apollo Lunar Module on the lunar surface
Spacecraft are vehicles capable of controlling their trajectory through space.
The first 'true spacecraft' is sometimes said to be Apollo Lunar Module,[14] 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.
Propulsion
Main article: Spacecraft propulsion
Spacecraft today predominantly use rockets for propulsion, but other propulsion techniques such as ion drives are becoming more common, particularly for unmanned vehicles, and this can significantly reduce the vehicle's mass and increase its delta-v.
Launch systems
Main article: Launch vehicle
Launch systems are used to carry a payload from Earth's surface into outer space.
Expendable
Main article: Expendable launch system
Most current spaceflight uses multi-stage expendable launch systems to reach space.
Reusable
Main article: Reusable launch system
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This section needs to be updated. Please update this article to reflect recent events or newly available information. (August 2019)
The first reusable spacecraft, the X-15, was air-launched on a suborbital trajectory on July 19, 1963. The first partially reusable orbital spacecraft, the Space Shuttle, was launched by the USA on the 20th anniversary of Yuri Gagarin's flight, on April 12, 1981. During the Shuttle era, six orbiters were built, all of which have flown in the atmosphere and five of which have flown in space. The Enterprise was used only for approach and landing tests, launching from the back of a Boeing 747 and gliding to deadstick landings at Edwards AFB, California. The first Space Shuttle to fly into space was the Columbia, followed by the Challenger, Discovery, Atlantis, and Endeavour. The Endeavour was built to replace the Challenger, which was lost in January 1986. The Columbia broke up during reentry in February 2003.
The Space Shuttle Columbia seconds after engine ignition on mission STS-1
Columbia landing, concluding the STS-1 mission
Columbia launches again on STS-2
The first automatic partially reusable spacecraft was the Buran (Snowstorm), launched by the USSR on November 15, 1988, although it made only one flight. This spaceplane was designed for a crew and strongly resembled the US Space Shuttle, although its drop-off boosters used liquid propellants and its main engines were located at the base of what would be the external tank in the American Shuttle. Lack of funding, complicated by the dissolution of the USSR, prevented any further flights of Buran.
Per the Vision for Space Exploration, the Space Shuttle was retired in 2011 due mainly to its old age and high cost of the program reaching over a billion dollars per flight. The Shuttle's human transport role is to be replaced by the partially reusable Crew Exploration Vehicle (CEV) no later than 2021. The Shuttle's heavy cargo transport role is to be replaced by expendable rockets such as the Evolved Expendable Launch Vehicle (EELV) or a Shuttle Derived Launch Vehicle.
Scaled Composites SpaceShipOne was a reusable suborbital spaceplane that carried pilots Mike Melvill and Brian Binnie on consecutive flights in 2004 to win the Ansari X Prize. The Spaceship Company has built its successor SpaceShipTwo. A fleet of SpaceShipTwos operated by Virgin Galactic planned to begin reusable private spaceflight carrying paying passengers (space tourists) in 2008, but this was delayed due to an accident in the propulsion development.[15]
Challenges
Main article: Effect of spaceflight on the human body
Space disasters
Main article: Space accidents and incidents
All launch vehicles contain a huge amount of energy that is needed for some part of it to reach orbit. There is therefore some risk that this energy can be released prematurely and suddenly, with significant effects. When a Delta II rocket exploded 13 seconds after launch on January 17, 1997, there were reports of store windows 10 miles (16 km) away being broken by the blast.[16]
Space is a fairly predictable environment, but there are still risks of accidental depressurization and the potential failure of equipment, some of which may be very newly developed.
In 2004 the International Association for the Advancement of Space Safety was established in the Netherlands to further international cooperation and scientific advancement in space systems safety.[17]
Weightlessness
Main article: Weightlessness
Astronauts on the ISS in weightless conditions. Michael Foale can be seen exercising in the foreground.
In a microgravity environment such as that provided by a spacecraft in orbit around the Earth, humans experience a sense of "weightlessness." Short-term exposure to microgravity causes space adaptation syndrome, a self-limiting nausea caused by derangement of the vestibular system. Long-term exposure causes multiple health issues. The most significant is bone loss, some of which is permanent, but microgravity also leads to significant deconditioning of muscular and cardiovascular tissues.
Radiation
Once above the atmosphere, radiation due to the Van Allen belts, solar radiation and cosmic radiation issues occur and increase. Further away from the Earth, solar flares can give a fatal radiation dose in minutes, and the health threat from cosmic radiation significantly increases the chances of cancer over a decade exposure or more.[18]
Life support
Main article: Life support system
In human spaceflight, the life support system is a group of devices that allow a human being to survive in outer space. NASA often uses the phrase Environmental Control and Life Support System or the acronym ECLSS when describing these systems for its human spaceflight missions.[19] The life support system may supply: air, water and food. It must also maintain the correct body temperature, an acceptable pressure on the body and deal with the body's waste products. Shielding against harmful external influences such as radiation and micro-meteorites may also be necessary. Components of the life support system are life-critical, and are designed and constructed using safety engineering techniques.
Space weather
Main article: Space weather
Aurora australis and Discovery, May 1991.
Space weather is the concept of changing environmental conditions in outer space. It is distinct from the concept of weather within a planetary atmosphere, and deals with phenomena involving ambient plasma, magnetic fields, radiation and other matter in space (generally close to Earth but also in interplanetary, and occasionally interstellar medium). "Space weather describes the conditions in space that affect Earth and its technological systems. Our space weather is a consequence of the behavior of the Sun, the nature of Earth's magnetic field, and our location in the Solar System."[20]
Space weather exerts a profound influence in several areas related to space exploration and development. Changing geomagnetic conditions can induce changes in atmospheric density causing the rapid degradation of spacecraft altitude in Low Earth orbit. Geomagnetic storms due to increased solar activity can potentially blind sensors aboard spacecraft, or interfere with on-board electronics. An understanding of space environmental conditions is also important in designing shielding and life support systems for manned spacecraft.
Environmental considerations
Rockets as a class are not inherently grossly polluting. However, some rockets use toxic propellants, and most vehicles use propellants that are not carbon neutral. Many solid rockets have chlorine in the form of perchlorate or other chemicals, and this can cause temporary local holes in the ozone layer. Re-entering spacecraft generate nitrates which also can temporarily impact the ozone layer. Most rockets are made of metals that can have an environmental impact during their construction.
In addition to the atmospheric effects there are effects on the near-Earth space environment. There is the possibility that orbit could become inaccessible for generations due to exponentially increasing space debris caused by spalling of satellites and vehicles (Kessler syndrome). Many launched vehicles today are therefore designed to be re-entered after use.
"Tight" style in the Loop - impromtu snap session wtih Nichole - D600 w/ Nikkor 105 f2.0 DC lens. Leggings here… blackmilkclothing.com/
Prozac09 loves to watch videos from earlier times. Different to photos the amount of videos that I have is rather limited. But this one he is watching here is one of his favorites. He just wants to watch it again and again. And he starts to synchronize his own laughing (which is real by the way) with the laughing he did 2.5 years ago (I do not even remember what we did originally to make him laugh like that).
Stagecoach East Kent Enviro 200 36880 (GN13 EYR) with Loop branding is seen in Canterbury on 26th June 2017.
Entrance to Bachelor Loop, a 17-mile loop up the canyon north of Creede, CO. Lots of old silver mine relics along the trail. Our ride is a 2025 Chevy Colorado ZR2. Bachelor Loop isn't much of a challenge for it, but we saw some beautiful country on a perfect fall day.
colder fall day - leaves went to past peak in the last week but still pretty awesome colors - had a fun loop w/ teagan, lots of dogs and other mtb's...
37409 and 37259 take a breather in Abington Down Loop with an extremely late running (due to loco failure, hence the class 37 substitution) 4S53 Daventry-Coatbridge, to allow 350406 to pass on a Manchester Airport-Glasgow Central service to pass. 7th November 2014.
re-purposed vinyl LP (the Bar-Kays' "Nightcruising") illustrating a section of the Chicago Perimeter Ride map
In appalling external condition to match the weather conditions, Army Department '196' (Hunslet Works No.3796 built in 1953) of the Longmoor Military Railway, bearing a fictitious BR number 68011 applied for an earlier filming sequence and explaining its bad external condition for a military loco, struggles to gain adhesion as it travels around the Holywater Loop section of the Longmoor Military Railway on the occasion of a railtour by the R.C.T.S. on a wet and dismal 16th April 1966. Thankfully at least one photographer braved the conditions to achieve this atmospheric photo in far from hospitable conditions. The organisers acknowledged the disappointment for the participants and arranged a re-run of the commemorative occasion later in the month.
© Gordon Edgar collection - all rights reserved. Please do not download, copy or use this image without my explicit prior permission