Vortex around our planets
Some spacecraft are showing signs of age or failure, others just don't seem to want to communicate anymore. Nevertheless, the group does a great job in space and delivers mountains of data every day about distant worlds, adventurous phenomena and last but not least about our planet and those that used to be there. And there was no shortage of supplies this year either.
It has been more than thirty years since a spacecraft last brought rock samples from outside – namely from the moon – to earth. Thanks to the Russian Luna missions and the American Apollo program, we lightened our satellite by more than three hundred kilograms. Despite the enormous progress, however, it remained the only stolen goods from space for a long time. Until now, Nasa's Stardust mission met comet Wild 2 behind Mars orbit and stole dust from its tail. On January 13, 2006, the landing pod returned to Earth with the valuable cargo.
The mission was successful even with the naked eye. The first analyzes amazed the scientists, as they turned the previous picture of comets upside down: rocks in the samples must have formed at extremely high temperatures. This contradicts the previous theory, according to which comets formed exclusively from cold matter at the outer edge of the primordial solar nebula. A kind of mixing must have taken place in the early solar system, which transported the material that had formed in the hot interior to the outside. The analysis of the data is far from complete, but will certainly keep the researchers busy for years to come.
The view of the neighbor …
The scientists were also certainly happy to hold some rock samples in their hands from the red planet, which has always fired people's imaginations. But so far they have had to be content primarily with beautiful pictures. In March, the Mars Reconnaissance Orbiter (MRO), which started its journey last August, also reached its destination. The dangerous pivoting maneuver into the orbit of the planet was successful. Not a matter of course, because in the last two years two probes have gone missing. There are now a total of three functioning scouts orbiting Mars – for a short time there were even four, but at the beginning of November, after almost ten years in space, radio contact with the Mars Global Surveyor broke off.
In terms of its high-resolution camera, however, the MRO is far superior. With this and five other scientific instruments, he is supposed to look for – how could it be otherwise – water. But the space agency also uses his eyes to look out for landing sites for people and technology. Reinforcements are already planned: in the coming year, the Phoenix space probe is expected to begin its year-long journey to Mars, and in 2009 a Mars laboratory in the form of a rover is to follow. NASA sees the first manned space flight with six astronauts from 2025.
According to scientists from the University of California at Berkeley, however, a walk on Mars could be anything but pleasant. In early August, they speculated about violent hurricanes at the planet's surface, ultimately contributing to the production of highly reactive hydrogen peroxide. Thus, the surface of Mars could turn out to be even more hostile to life than previously thought. When this disappointment was almost forgotten (or suppressed) by all Mars friends, there was even new hope at the beginning of December: photos taken by the Mars Global Surveyor in 2004 and 2005 show a crater wall with more than a kilometer-long traces reminiscent of gullies. In images taken four years earlier, the scientists only noticed uninterpretable brighter areas there. So is there water on Mars and maybe life with it? Critics curb the enthusiasm – it may be debris that has slipped or flowing carbon dioxide. To clarify the question, the researchers rely on the SHARAD radar on board the MRO - at least theoretically it should be able to detect water veins under the surface of Mars.
… and to the neighbor
Venus also welcomed a new guest on April 11 of this year: Venus Express. She last visited the US probe Magellan 16 years ago. For the Europeans, the flight to our neighboring planet is a first. The satellite will orbit the planet, which is similar in size, mass and composition to Earth, for two Venusian days, i.e. 486 Earth days. The aim of the mission is to better understand the properties of the atmosphere and surface, such as temperature, density and composition.
Just a few days after its arrival, the probe photographed the cloud formations over the south pole of Venus for the first time. In mid-December, the European Space Agency Esa announced that the average temperature on Venus is around 460 degrees Celsius. In the mountains, however, it is up to thirty degrees colder than in the lowlands. The high average temperature is caused by a strong greenhouse effect, which no longer allows energy supplied by the sun to escape from the atmosphere.
Outcast Dwarf
Not about exploration, but about the definition of the planets was the subject of a heated discussion that caused a stir in August. The impetus for this came from the countless celestial bodies with planet-like masses that scientists discovered in the outer regions of the solar system. According to the first suggestion, which is based on the mass of the celestial body, we would suddenly have twelve planets. For example, the asteroid Ceres and Pluto's moon Charon would have been given planetary status. However, the General Assembly of the International Astronomical Union (IAU) had to approve the draft.
And that's exactly what she didn't do. On August 24, the IAU decided to demote Pluto to a dwarf planet. Accordingly, our solar system now consists of the eight planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Pluto now ranks under the official number "134340" and is just one of many. But there is resistance, because by no means all astronomers and planetary researchers agree with the new definition. They plan to ignore the change until next year and try to restore Pluto's honor at another IAU General Assembly - but so far it's only scheduled for 2009.
Perhaps it is comforting that on January 19th, for the first time in the history of space travel, an expedition to Pluto set off. About nine years later, the NASA New Horizons space probe is to fly past the planet, pardon dwarf planet, and its moon Charon at a distance of around 10,000 kilometers and study both up close.
Icy Lack…
Despite or perhaps because of its close proximity to Earth, our moon is still the target of many missions. The European probe Smart-1 crashed on Earth's satellite on September 3 after its almost three-year research trip. The impact of the 366 kilogram probe left a crater up to ten meters wide and whirled up a lot of dust. However, the primary purpose of the mission was to test new technologies, such as a solar-electric ion engine. The Europeans also want to use this propulsion technology for a planned flight to Mercury and for further space expeditions.
But exploring the surface of the moon was also on Smart-1's agenda. For the first time, images of the far side of the moon have been taken. This revealed an area at the North Pole that is never in shadow. The Cornell University researchers, on the other hand, aimed their ground-based telescope at the permanently dark craters at the moon's south pole. With the help of high-resolution radar measurements, they proved that, contrary to previous assumptions, there are no traces of frozen water there.
About seven years ago, researchers using the Lunar Prospector probe believed they had found evidence of high concentrations of hydrogen. The sobering realization is likely to affect Nasa's plans for another moon landing and the construction of a moon base. And the US President may be disappointed too - just under three years ago he announced to the world his newfound interest in the moon as a stepping stone to Mars.
… and glowing insights
In other areas, however, things are looking better for NASA: After a delay of almost two months, the Stereo space probe pair was launched on the night of April 26. October. It will study the sun and its destructive eruptions, unleashing the energy of billions of atomic bombs in just a few minutes. In the process, several billion tons of matter from the sun's atmosphere are thrown into space. As the solar wind, the charged particles collide with the earth's magnetic field and cause the beautiful auroras, but also affect or damage satellites and disrupt telecommunications and energy supplies.
Images taken by the two probes from different angles should be combined to produce a three-dimensional picture of the solar flares. In this way, outbreaks can be better predicted in the future. The Japanese space agency sent its Solar-B space probe into space at the end of September for this purpose. The orbit is synchronized with Earth orbit so that the satellite is in sunlight for at least nine months per year. He is to investigate the connection between the magnetic fields of the sun and the activity on its surface. There could soon be more reliable forecasts for space weather.
Hubble can hope…
The researchers are only speculating as to whether the cosmic radiation last June damaged the main camera on the Hubble space telescope or whether the electronics simply failed. At the end of October, NASA announced that Hubble would be equipped with new instruments, gyroscopes, spare parts and batteries in a fourth and final service mission. A total of four to five manned spacewalks are required. Maintenance work for the telescope was actually scheduled for 2004, but this was canceled after the crash of the space shuttle Columbia. Thanks to successful shuttle flights, the space veteran should be back in mid-2008 so that it will soon be able to provide us with razor-sharp images of the universe again.
However, he doesn't look back as far as this year's Physics Nobel Prize winners John Mather and George Smoot with the Cobe satellite, which was launched in 1989. With its help, they researched the cosmic background radiation, which has been traveling through the universe as a relic of the Big Bang for almost 14 billion years. For the first time, they were able to detect structures in the radiation that otherwise hits the earth uniformly. They also showed that it is thermal radiation. In doing so, they confirmed previously hypothetical concepts, in particular the Big Bang theory, and aroused the interest of physics in this topic. They accepted their award in Stockholm in December.
… and Thomas Reiter home
The first Swede in space also comes from this city: Christer Fuglesang. On December 10, he and six colleagues set out for the ISS to carry out fieldwork for repair and maintenance work. After the 12-day mission, the Shuttle Discovery will also bring German astronaut Thomas Reiter back to Earth, who has been on board the space station since early July. He landed in Cape Canaveral just in time for Christmas and is now – after months in weightlessness – slowly getting back on his feet.
