2014 was a good year for excitement about space. We look at the story of spaceflight so far, and where it’s going next…
It was the beginning of the 20th century when Soviet scientist Konstantin Tsiolkovsky wrote his book The Exploration of Cosmic Space by means of Reaction Devices, but it wasn’t until the 1920s that “rocket science” – in the interplanetary sense – became a serious school of engineering, when his follower, American Robert Goddard, published a paper demonstrating a method of fueling rockets that would provide enough power for reaching space to become a real possibility. It was in 1944, with the German V-2 rocket, that the first manmade craft reached space, at 108.5 miles.
Though this is an unfortunate place for our beginnings to have been carved, space exploration and science has led to widespread international collaboration. After World War 2 came the Cold War, and the Space Race. In 1975, whilst tensions were lulled somewhat, Soviet cosmonauts and American astronauts worked together in history’s first international manned spaceflight. An Apollo spacecraft and a Russian Soyuz met in low Earth orbit and docked, while the crews spent two days performing experiments.
The Russians took the early lead in the space race. In 1957, the USSR successfully launched the first man made satellite into orbit around the Earth. Sputnik 1 broadcast radio pulses from its antennae, which could be detected from the Earth. It may not seem like much, but scientists were able to obtain valuable data on the upper atmosphere and beyond from the drag on the satellite, and the propagation of the radio waves. They also claimed victory with the first person ever to go to space, cosmonaut Yuri Gagarin, in 1961. The Vostok 1 craft made one complete Earth orbit, and the flight lasted 108 minutes. On landing, Gagarin was ejected from his reentry craft and landed softly by parachute.
We were also curious about the other worlds around us, and naturally also explored them, starting with our closest neighbour and Earth’s natural satellite, the Moon. Again it was Russia who made the first contact, in September 1959, when the Luna 2 probe made impact on the Moon’s surface. It was followed less than a month later by Luna 3, which went to the far side of the moon and sent back pictures which are still iconic today. These missions, of course, were followed by many more, including rovers and the missions carrying the 12 Apollo astronauts who walked on the moon.
After the moon, our next closest target was Venus. Very little was known about it before we sent craft there, other than that it was a roughly similar size to Earth. The first craft to make a flyby was Mariner 2 in 1962, which used microwave and infrared radiometers to measure the temperature of Venus, as well as detecting charged particles from the Sun with its other detectors. The first craft to reach the surface was the Soviet lander Venera 7 in 1970. After its predecessor Venera 4 had probed Venus’ atmosphere further to find that it was denser than expected, Venera 7 followed. It had a quicker descent than planned when the parachute appeared to fail, but did manage to send back temperature readings of 475*C from the surface.
In the 1970s we got around to visiting our farther-off neighbours, the gas giants. Voyager 1 and Voyager 2, launched in September and August 1977 respectively, made use of a rare planetary alignment and used Jupiter’s large gravity to assist their flights. Voyager 2 took a slower path and visited all four of the outer planets, while Voyager 1 performed flybys of Jupiter (in 1979) and Saturn (in 1980) then went on to travel out of the Solar System and into interstellar space. One of the most memorable features of the Voyagers are the gold discs they each have attached, holding information about Earth and its inhabitants, a collection of sounds and music, and a depiction of where we are in the galaxy. We have since sent orbiter missions to both Jupiter and Saturn: Galileo launched in 1989 and reached Jupiter in 1995, giving us extensive data on Jupiters atmosphere, magnetic field, and inner moons, and Cassini-Huygens launched in 1997, arriving at its destination in 2004 and having so far put in ten good years on the clock, including discovering evidence for underground liquid water on Saturn’s moon Enceladus. To date, Voyager 2 is the only craft to have visited Uranus or Neptune.
Recent excitement over the Rosetta Philae lander on Comet 67P created a bigger ripple among the public and general media than many astronomers and scientists expected. Some of the big space news to look out for in the future includes:
2015: Rosetta, Dawn, Hubble Rosetta hasn’t finished its mission yet; it will continue to stick with the comet through its closest approach to the sun, montior the way it changes as it approaches. Dawn is the NASA craft that has been exploring the asteroid belt between Mars and Jupiter, and in March is headed to the dwarf planet Ceres, the largest object in the asteroid belt, containing about 1/3 of the mass. And of course, the Hubble telescope turns 25 in April! Happy Birthday Hubble!
2016: Juno The Juno spacecraft launched on August 5th 2011 and is expected to reach Jupiter in July 2016, when it will set itself in orbit, and then complete 33 orbits of Jupiter over the course of about a year before deorbiting and crashing into the planet. It will measure properties of Jupiter’s atmosphere, hopefully confirming or denying current planet formation theories, and map its magnetic and gravitational fields, to discover the deep structure of Jupiter.
2018: ExoMars A new Mars rover from the European Space Agency, this is very much a home-grown project, with EADS Astrium leading the engineering. ExoMars stands for Exobiology on Mars, and unsurprisingly it will be continuing our desperate search for signs that there might ever have been life on the red planet.