NASA at 50

Minnesota public radio is one of the many media currently celebrating this year’s fiftieth anniversary of NASA with a program yesterday on its history. The BBC also collected a series of videos of many of the space agency’s memorable moments, while Wired had an article about NASA’s half century of “towering achievements”. Kansas City Infozine interviewed several NASA veterans to talk about its accomplishments. The first of several 50th anniversary moments was last month with the signing of the act that brought NASA into existence.

The birth of NASA was the necessity of catching up with the Russians. On 4 October 1957, the Soviet news agency Tass announced to the world that the USSR had successfully placed Elementary Satellite 1 into an elliptical orbit about 900km above Earth. Elementary Satellite 1 became better known by its diminutive "Sputnik". It circled the globe every hour and a half and flew over America seven times a day, in almost taunting fashion. At the height of the Cold War, the Soviet Union had taken a giant technological leap ahead of the US.

When the general American public read about Sputnik, there was much predictable shock and surprise. The Space Age had begun, and it had nothing to do with American might. Many others felt that the oceans could no longer protect the mainland and the Russians had intercontinental warhead capability. The Eisenhower administration rushed to reassure the American people, but also offered their congratulations to Moscow for its achievement. US scientists were simply excited knowing that Sputnik was just the incentive needed to get their satellite program up and running.

Public opinion was now massive in favour of the creation of an aggressive exploration of space. And so, on 29 July 1958 US President Dwight Eisenhower signed the National Aeronautics and Space Act. The act would lead to the birth of National Aeronautics and Space Administration (NASA) on 1 October that year. The act provided for “research into problems of flight within and outside the earth's atmosphere, and for other purposes.” It declared that activities in space should be devoted to peaceful purposes for the benefit of all mankind and would require “adequate provision”. The act’s eight objectives were to expand knowledge of space, improve the quality of space vehicles, develop space travel for humans, establish long-range scientific studies, preserve the US role as leader in space, using military discoveries for civilian purposes, co-operation with other nations, and effective utilisation of US scientific and engineering know-how.

Since 1915, the field of aeronautic research had been the province of the National Advisory Commission for Aeronautics (NACA). NASA absorbed the NACA and kept the “Aeronautics” in its name. It also took NACA’s 8,000 employees, its $100 million annual budget, its three major research laboratories (Langley and Ames aeronautical laboratories and Lewis Flight Propulsion Laboratory) as well as two smaller test facilities.

The new organisation launched into space exploration programs with Project Mercury. With a well-honed media instinct, NASA decided from the outset its space program would need to be manned in order to keep the public onside. In 1961, Mercury began to pay dividends. In May, Alan Shepard became the first American in space, with a 15-minute suborbital mission. Eight months later, John Glenn became the first true US astronaut when he orbited the Earth. Project Mercury’s six flights achieved the goal of putting piloted spacecraft into Earth orbit and retrieving the astronauts safely.

Project Gemini built on the carefully-planned success of Mercury. Gemini had two-person missions, re-entry rockets within the capsule and the ability to alter its orbit. But on 25 May 1961, President Kennedy raised the stakes again with his “special message to the Congress on urgent national needs”. Given just a month after Yuri Gagarin became the first man in space, This famous speech called for America to take “longer strides” and take a leading role in space achievement. He committed the US to landing a man safely on the moon by the end of the 1960s and ten billion dollars to fund it.

Kennedy's speech was pure gold to NASA. His estimate as to the cost of the Apollo program was grossly inadequate and it had ballooned out to $25.4 billion by the time it ended. The program overcame the setback of the fire to the Apollo 1 capsule on the ground that killed three astronauts. For all future missions, most flammable items were replaced with self-extinguishing materials, pure oxygen was replaced by a nitrogen-oxygen mixture at launch and the hatch was redesigned to open outward and to be removed quickly.

NASA’s crowning moment came when Neil Armstrong carried out Kennedy’s goal, on time (though over budget) on 20 July 1969. The 17th mission brought an end to the Apollo program in 1972 and NASA looked to new challenges. In 1975, they docked in space with a Russia Soyuz craft in the world’s first international manned space flight. When US astronaut Thomas Stafford shook hands with Soviet Cosmonaut Alexei Leonov in the docking ring of joined Apollo and Soyuz spacecraft, it was an act that seemed to mark the end of the Space Race.

In the eighties, NASA returned to human spaceflight with the Space Shuttle program. The first flight of STS-1 (named “Columbia”) in 1981 demonstrated that it could take off vertically and glide to an unpowered airplane-like landing. But the 1986 Challenger disaster on take-off and the 2003 Columbia disaster on landing, seriously damaged NASA’s credibility and made it look for less awe-inspiring challenges. President Bush’s subsequent 25 year plan to return to the Moon and land on Mars has not met with the same enthusiasm as Kennedy’s earlier call.

But there have been many other successes in NASA’s unmanned program. The Hubble Space Telescope has greatly advanced cosmology and returned thousands of astonishing images after its mirror was fixed in 1993. NASA's scientific probes have explored the Moon and all the planets of the solar system except Pluto. Voyager 1 is now the further man-made object in space and is now in the heliosheath on the edge of interstellar space some 16 billion kms away from its home planet. And a new expanded space race is at hand with Japan, China and the EU joining the traditional players. American scientists now say they need the support of private enterprise to succeed in space. But despite concerns about its middle-aged spread, it is hard to imagine the future colonisation of space without some role for NASA.

Plutoid on the Makemake

The International Astronomical Union (IAU) has named its first plutoid. The Kuiper belt object formerly known as 2005 FY9 has been rechristened “Makemake” and classified as both a dwarf planet and plutoid. Makemake is fifty times further away from the Sun than we are and its orbital period is 310 Earth years. It has an apparent magnitude of about 16.7, which makes it bright enough to be visible using high-end amateur telescopes. The plutoid is named for a Polynesian God and is pronounced “mahki-mahki”.

The IAU announced the new category of plutoid last month at a meeting of its executive committee in Oslo. The category covers what it calls “transneptunian dwarf planets similar to Pluto”. Plutoids orbit the Sun at a distance generally greater than that of Neptune and have a minimum defined magnitude of brightness. Makemake now joins the two other two known and named plutoids Eris and Pluto itself. The IAU fully expects that more plutoids will be named as science progresses and new discoveries are made.

The plutoid Makemake was discovered in Easter 2005 by astronomers at California’s Palomar Observatory. According to Mike Brown, who led the Caltech team that found the object, they nicknamed it “Easterbunny”. The IAU preferred to give it the interim name of 2005 FY9 but after six months of lobbying they accepted a proposal from Brown's team to rename it to Makemake. Brown says the planet is two thirds the size of Pluto and is the brightest object in the Kuiper Belt after Pluto itself. He says the surface is “covered with large amounts of almost pure methane ice, which is scientifically fascinating, but really not easily relatable to terrestrial mythology.”

Brown is also the discoverer of Eris which ultimately led to Pluto’s demotion from the major planets. The existence of Eris drastically heated up the debate over how to define a planet with over a dozen other candidates vying for acceptance. In 2006, it seemed as if the IAU was going down the path of greatly expanding the list of solar system planets but instead decided there were would only be eight. Pluto and Eris (then called 2003 UB313) joined a new category called dwarf planets which also included Ceres which lies in the asteroid belt between Mars and Jupiter. However because of its location, Ceres can not be considered a plutoid.

In keeping with the original “Easterbunny” nickname for the newest plutoid, Makemake is named for the supreme god of Rapa Nui (Chile's Easter Island). Makemake was the creator of the first humans and the patron of the Tangata bird cult. He was worshipped in the form of sea birds, which were his incarnation. His material symbol, a man with a bird's head, can be found carved in petroglyphs on the island. With his divine power he makes the plants and animals grow. Some believe that the huge statues on the island are connected to his cult. Easter Island was first visited by Europeans on Easter Sunday 1722, exactly 283 years before the plutoid was discovered.

The Tunguska Event: One hundred years on

Scientists have gathered today in Siberia to commemorate the hundredth anniversary of the Tunguska Event. One hundred years ago today, a fireball streaking across the sky caused a massive explosion in the Siberian hinterlands which marks the largest recorded collision between Earth and an object from space. Although largely unnoticed at the time, the explosion measured five on the Richter scale and destroyed a 2,500km area of taiga forest. But because of the area’s isolation hardly anyone died and it would take 21 years for a scientific expedition to reach the scene of the devastation.

Tunguska was the largest cosmic impact event on Earth in recent history. At 7:17am local time on 30 June 1908 a shock wave flattened 80 million trees in Siberia near the Podkamennaya Tunguska River in what is now the Krasnoyarsk Krai region in central-Eastern Russia. Because of its remoteness no-one is entirely sure what happened. The most likely reason for the explosion is a meteorite which exploded at an energy force of somewhere between 10 and 15 megatons, about a thousand times more powerful than the atomic bomb that destroyed Hiroshima.

The shock waves of the Tungunska explosion were monumental. They circled the globe twice and were registered by all observatories. In Irkutsk, 1,500kms away, a seismograph scale went wild. The ground trembled as far as Tashkent in Uzbekistan (Central Asia), Tbilisi in Georgia (South Caucasus) and even Jena, Germany. Barometers in the UK registered atmospheric pressure fluctuations. The blast caused a four-hour magnetic storm which closely resembled the geomagnetic fluctuations registered after high-altitude nuclear blasts. Over the next few days “white nights” and unusual silvery clouds were seen over the vast territory from Siberia to Europe’s western borders.

The Tunguska event is one of the most mysterious and well-studied 20th century phenomena. Evidence is elusive and only a few traces of its existence were found. The most likely explanation is an exploding fragment from a disintegrating meteorite but scientists concluded there was no actual impact. The meteorite was probably travelling at around 34,000 kms per hour when it exploded about 8km above the Earth's surface. According to local accounts a bluish fireball appeared in the sky which was followed by a flash ten minutes later. Then there was a deafening explosion that was heard 500 km away. The ground began shaking as in an earthquake, and a hot wind blew across the land, singeing crops and shattering windows.

Closer to the explosion, the object was seen in the cloudless, daytime sky as a brilliant, sun-like fireball. At distances around 60 km, people were thrown to the ground or even knocked unconscious; windows were broken and crockery knocked off shelves. The closest observers were reindeer herders asleep in their tents in camps about 30 km from the epicentre. They were blown into the air and knocked unconscious; one man was blown into a tree and later died. According to one survivor "Everything around was shrouded in smoke and fog from the burning fallen trees."

Scientists now suspect a stony asteroid exploded in mid-air because of high-pressure air resistance. From the explosion a boulder flew out at a slightly skewed angle which blasted out a crater. Later it filled in with water and sediments that disguise its shape today. New seismic studies show a candidate rock is buried under the lake. This summer Italian scientists will return to the scene at Lake Cheko to check out if this is the asteroid that flattened the forest.

But others are less certain and remain convinced the mystery will survive another hundred years. Wilder theories include an alien spacecraft which blew up, or that a black hole made a freak appearance. The problem is caused by the fact that no evidence was obtained at the time of the blast. Because of the chaotic conditions in Russia at the time, the first scientific expedition to the scene of the explosion did not arrive until Soviet times in 1927. Professor Leonid Kulik led an expedition there but was unable to establish the cause of the conflagration two decades after the fact.

To this date, no-one has found a crater which might identify the ‘ground zero’ for the explosion. But the fallen trees acted as markers pointing away from the epicentre. Kulik’s team estimated the asteroid entered Earth's atmosphere travelling at a speed of about 54,000 km per hour. During its quick plunge, the 100-million-kilo space rock heated the air surrounding it to over 20,000 degrees Celsius releasing the energy of 200 atomic bombs. On average, a Tunguska-sized asteroid will enter Earth's atmosphere once every 300 years, so if statistics are right, we have 200 years to prepare for the next holocaust from space. Equally intriguingly, had the explosion had occurred some five hours later, it would have completely destroyed the then Russian capital of St. Petersburg. How would the 20th century have turned out if the Tsar had died then at the hands of nature instead of a decade later at the hands of the Bolsheviks?

Dark matters: life, the universe and everything

On Wednesday NASA launched a rocket carrying its new $690 million long distance telescope it hopes will provide answers to some of the universe’s enduring mysteries. The Delta II rocket blasted off from Kennedy Space Center carrying aboard the Gamma Ray Large Area Space (GLAST) telescope. After a 75 minute flight, GLAST was deployed into a low Earth orbit and NASA expect it to transmit its first data in three weeks time. “After a 60-day checkout and initial calibration period, we'll begin science operations," said Steve Ritz, project scientist at Goddard Space Flight Center in Washington DC. "Glast soon will be telling scientists about many new objects to study, and this information will be available on the internet for the world to see."

GLAST is designed to study high energy sources of radiation in the universe. The project is a five to ten year operation designed to detect high energy gamma ray bursts, pinpoint their origin and shed light on the black holes where they mostly seem to reside. According to NASA, the new telescope will give astronomers a superior tool to “study how black holes, notorious for pulling matter in, can accelerate jets of gas outward at fantastic speeds.” The idea is to use a form of light invisible to the human eye to study and trace the origins of one of the most powerful forms of energy known - gamma ray bursts.

Gamma rays are energy-laden electromagnetic radiation produced by sub-atomic particles. They sit at the lowest end of the electromagnetic spectrum beyond ultraviolet and x-rays with a tiny wavelength of 0.00001 millimetres (ten to the power of minus five). They are found in the hottest areas of the universe and are produced by dramatic events such as supernova explosions, destruction of atoms, and the decay of radioactive material in space. A gamma ray burst release can travel across vast distances of the universe, and are absorbed by the Earth's atmosphere. Gamma ray bursts are spectacular events and can release more energy in ten seconds than the Sun will emit in its entire ten billion year life.

Scientists are particularly interested in gamma ray bursts because they throw light on some of the earliest events in the universe. They are so bright they can be detected as far back as the earliest five percent of the universe’s life time – over 13 billion years ago. One of the aims of GLAST is to investigate the link between gamma rays and dark matter. They hope to confirm that gamma ray bursts from the centre of our galaxy will reveal the presence of dark matter. Although known to science since 1933, dark matter remains one of science’s more hypothetical concepts. Yet it is believed to account for the majority of the mass of the observable universe.

The discovery of dark matter was made by Swiss astrophysicist Fritz Zwicky who worked at the California Institute of Technology in the 1930s. Zwicky was aware of Edwin Hubble’s discovery that the universe was expanding. But he was also aware that galaxies tend to cluster in complicated local movements. He measured the red shift from individual galaxies to see what was holding them together. What he found astonished him: a cluster of galaxies can remain bound together for billions of years, but only if it contains enough material to trap the individual members. But when Zwicky calculated the combined gravity of the known components – stars, gas and dust – it was nowhere near sufficient to form the cluster.

Zwicky concluded there must be an extra contribution to the gravitational pull. This unknown force outweighed the visible stuff hundreds of times over. He called this material “dark matter”. While Zwicky’s findings were initially ignored, a gradual weight of evidence emerged to show, as scientist Paul Davies says, “the luminous parts of galaxies represent just the tip of the iceberg, and that most of the matter in the universe is in fact dark”.

It is dark matter that keeps the galaxy in the familiar disk shape and it is dark matter that ensures the Sun stays firm on its 250 million year circuit of the Galaxy. Without it, the Milky Way would unravel like an exploding flywheel. Ever keen to find human significance in the universe, Scientists have come up with bizarre anthropomorphic names to describe the types of dark matter they think might be out there. There are two broad categories: MACHOs and WIMPs. MACHOs are “Massive Compact Halo Objects”. These are concentrations of mass residing in the galactic halo. They include dwarf stars and giant planets as well as smaller objects such as asteroids and comets. These objects are too dim to show up in telescopes but still exist in abundance. Yet MACHOs probably count for only a small percentage of dark matter. The rest are likely to be WIMPs.

WIMPs are Weakly Interactive Massive Particles. They are not so much dark as invisible, mostly passing through ordinary matter without betraying their existence. Because dark matter is concentrated at the centre of galaxies, scientists envisage a thick invisible soup of WIMPs through which stars swim as they perform their loop across the Milky Way. As WIMPs are weakly interacting, they only very rarely hit an ordinary atom; and as they are massive particles, possibly as heavy as a uranium atom they could account for the remaining dark matter in the galaxy.

Most importantly, dark matter played an essential role in shaping the universe. The smoothness of the early life of the universe was removed as regions over-dense in dark matter drew on surrounding material to amplify their denseness. Normal matter alone would have been too feeble to create galaxies, stars and planets and dark matter was needed to assist the clumping process. Peter Michelson, a Stanford astrophysicist and a lead investigator on the GLAST project, describes dark matter as “"mysterious, unseen substance that gravitationally holds the universe together”. He hopes the glimpses of gamma ray bursts will provide clues as to how dark matter formed the universe. "When you look at the night sky with your eyes, it is fairly quiescent and peaceful," Michelson said. "The gamma ray sky is not. It's a very different view of the universe. We're seeing exotic things like black holes and neutron stars and coalescing binary systems at the end of their life when they collapse into a black hole and there's an explosion."

Christmas Eve

In Australia, as in many western countries, Christmas Eve is the epitome of the tension between capital and Christmas. The media usually presents this ‘last minute spending spree’ as an unalloyed positive. This may reflect the nature of the relationship between media and their customers, the retailers that spend so much in advertising. No thought is given to whether this consumption is a good thing. Scopical reported gleefully an $800 million spent across the nation today. They quoted the Retailers Association’s executive director who said, "It'll be a healthy Christmas for retailers, who want their cash registers ringing long and loud." The valid warnings from economists about rising inflation seemed almost carping in comparison.

The Fairfax outlets also today reported the NSW Business Chamber statement that Christmas shoppers have spent $6 billion across Australia in the month prior to Christmas, up six per cent on 2006. In particular, electrical goods such as plasma screens, DVD players and MP3 players did well - with sales up 13 per cent on last year. While the article did talk about debt-funded spending and increased petrol prices, there was nothing in the frame of this of how this fits in with global warming and the need to reduce consumption. The media, in collusion with their advertisers, will be a long time coming round to this argument.

But not all Christmas Eve activity is about commercial interests. For many cultures, the night of Christmas Eve is the highpoint of the Christmas festival. In Spanish speaking cultures, Christmas Eve is known as “La Nochebuena” (the Good night). Family members gather around nativity scenes common to most homes. Christmas dinner (often Pavo Trufado de Navidad – Christmas turkey with truffles), games and song are followed by La Misa del Gallo (Rooster’s Mass) at midnight. La Misa del Gallo is so called because of the tradition that the only time the rooster crowed at midnight was at Jesus’ birth.

In Scandinavia, Christmas Eve is also the highlight of the festive calendar. It gets dark in some parts of Sweden by 2pm at this time of year and the locals are anxious to make the most of the long evenings. Swedes hang lighted stars and put electric candleholders in the windows. On Christmas Eve (Julafton) homes are alive with the smell of baking which ends in a huge Christmas Eve dinner followed by present giving usually done by someone dressed up as a tomte or Christmas gnome.

But one Swedish consultancy firm are determined to turn a Christmas tradition on its head. Stockholm-based Sweco have done an analysis on population centres and the rotation of the Earth's axis and worked out that the best place for Santa’s Grotto would be a remote location in northern Kyrgyzstan at latitude, (N) 40.40 longitude (E) 74.24 to be precise. The theory is if he starts there and travelled west against the rotation of the Earth, Santa then has twice as much time to deliver presents on Christmas Eve then if he had started at the North Pole. Given the Arctic melting issues, this may need to be looked into more seriously.

Back in the UK however, the rise of anti-social behaviour has claimed another casualty. Many churches have been forced to cancel their Christmas Eve midnight masses due to problems of violence caused by drunks and intruders. Church officials have reported attacks on clergymen in the run up to Christmas. Reverend Malcolm Liles said: "I have heard of several instances where clergy have been asked for money or have been assaulted in their churches." Liles and others are calling for better employment rights for ministers, including improved safety and an end to the situation where churches have no legal responsibility for the safety of the clergy, who are deemed to be employed by God.

Its not just the Christians who are celebrating, others are celebrating the ancient midwinter festival of Yule. Pagans gathered in Modesto, Kansas on 21 December to celebrate the winter solstice. It is the shortest day of the year in the northern hemisphere and the one where the Sun God supposedly dies and is resurrected. Twenty four druids, witches and warlocks walked through an archway while others wafted white sage smoke over them and before spraying holy water from the Irish Well of St. Brigid. The sage was meant to remove negativity while the water was a blessing.

Meanwhile much larger numbers were gathering for another religious rite. Over one million Muslims have made the pilgrimage to Makkah (Mecca) for the annual Haj. They completed the rituals which included stoning the Jamrat in Mina before performing the farewell tawaf in Makkah. Those left will stay in Mina to stone the Jamrat for the fourth day. Authorities were on high alert and imposed a strict one-way system to ensure there was no repeat of the incident at Jamrat bridge during the 2006 Haj when 362 people were killed in a crush. Makkah’s governor Prince Khaled Al-Faisal warned he had noticed that many pilgrims have sneaked into holy places without having a Haj permit. “We will find solutions to all these problems,” he warned.

And on a night traditionally associated with a guiding star, astronomers have gotten their own present for Christmas Eve. Tonight is the night the planet Mars is in syzygy and will be the second brightest object in the sky next to the Moon. Syzygy is when a planet is in opposition which means it lines up with the Earth and sun, with the Earth in the middle. Mars is in opposition once every 780 days. Michael Fauerbach, associate professor of physics and astronomy at Florida Gulf Coast University, says it will appear a couple of hours after dark. “It's impossible to miss,” he said. “It's a bright orange-ish object, and it's obviously not a star”.

Don’t tell that to the wise men. Happy Christmas.

Sputnik – 50 years on

Russia held celebrations yesterday at Star City to mark the 50th anniversary of the launch of the world’s first artificial satellite Sputnik 1. Scientists, engineers and cosmonauts gathered at the space training facility near Moscow to recall the launch of the small spiky module that began the world’s space race. Military officials also laid flowers at the grave of the father of the Soviet space programme, Sergei Korolyov, who is buried at the Kremlin walls.

Sputnik is Russian ("Спутник") for “travelling companion”. Sputnik 1 was an 83 kilo, 56cm diameter sphere with four antennas connected to battery powered transmitters. The transmitters broadcast a continuous "beeping" signal to a suitably impressed earthly audience for 23 days. Sputnik was tiny, barely twice the size of a football, but it could orbit the Earth in 96 minutes.

In 1952, the International Council of Scientific Unions (ICSU) decided to establish the International Geophysical Year (IGY) to coincide with the high point of the 11 year solar cycle of sunspot activity later that decade. By some quirk of science, this “year” lasted a whole 18 months from July 1957 to December 1958. The US embraced the IGY program with investigations of aurora and airglow, cosmic rays, geomagnetism, glaciology, gravity, the ionosphere, determinations of longitude and latitude, meteorology, oceanography, seismology, solar activity, and the upper atmosphere. But the ICSU called on its members to do something more: it wanted nations to launch a satellite to map the Earth’s surface.

By 1957 Russia was ready to answer the challenge. In August the Soviets tested their R-7 Semyorka the world’s first intercontinental ballistic missile. While the test failed, they designed a modified version of the R-7 for its first space test. Two months later, the R-7 launched Sputnik from the Baikonur cosmodrome in Kazakhstan. The US was so disturbed by this apparent victory for communism, President Eisenhower gave the go-ahead to create a new federal agency to co-ordinate its space program. NASA was born a year later.

But while the Americans played catch up, the Russians went on to further success. Within a month of Sputnik 1, the Soviets launched the dog Laika into orbit aboard Sputnik 2. Laika was a stray dog picked off the streets of Moscow to become the first living being in space. She didn’t last long. Although Russian authorities told the world, she survived for four days in space, in truth she died within hours of take-off as her pulse rate increased to three times its normal level probably due to overheating, fear and stress. Laika was the first of 13 dog launched into space by the Russian in the next ten years. Scientists used dogs because they could best stand the long periods of inactivity. All thirteen were female as they did not lift their leg to urinate.

The Sputniks led to a string of successes for the Russian space program. In 1961 the tiny Yuri Gagarin became a giant figure as the first man in space – it helped he was just 157cm tall. In 1965 cosmonaut Alexei Leonov exited the airlock of the Voskhod 2 spacecraft to make the first spacewalk. It wasn’t until the late 1960s that the US finally took the lead with its Apollo missions to the moon with its crowning achievement of Neil Armstrong landing on the surface of the Moon.

Fifty years after Sputnik, there are now more than 800 satellites orbiting the Earth. NASA now acknowledges the debt they owe to the pioneer spacecraft. Michael Griffin, NASA’s head, went to Moscow for the 50th anniversary celebrations. He told the Russian Academy of Science how important the early Russian work was. "Without Sputnik there would have been no Apollo,” he said. “Indeed, when the space race of the 1960s was over, it may be said that we in America lost some of our own momentum."

Moonage Daydreams

America will go back to the Moon in order to prepare for a trip to Mars in two decades. NASA announced yesterday they plan to resume manned missions to the Moon by 2020 with a view sending to a manned mission to Mars by 2037. NASA administrator Michael Griffin made the claim at the 58th International Astronautical Congress (IAC) in the Indian city of Hyderabad. But Griffin stated they would need help from the private sector to make it happen. He said greater private investment in satellite and rocket launches is needed to make such missions commercially feasible. “Space tourism may be the only way out to make space transportation economical,” he said. “[but], we have to evolve a mechanism to train the prospective tourists and ensure their safety”.

America is not alone as at least four other countries are planning moon missions. However, a top Indian scientist warned the same IAC conference we should not colonise the Moon or Mars. Dr MYS Prasad said their resources should be shared for the common good. Prasad, who is an Indian Space Research Organisation ISRO deputy director, said the space community needed to avoid the temptation to mine minerals from Moon or Mars until we create an environmentally friendly base. “The biggest ethical question before the space-faring nations is whether mankind is looking at ‘habitation or colonisation’ of Moon and Mars,” he said. “The construction and occupation of bases should be fundamentally treated as habitations rather than colonies in the conventional sense.”

Griffin's 'back to the moon by 2020' statement is a reiteration of a George W Bush claim in 2004. But with a Mars mission like to cost in excess of $1 trillion, it remains speculative at best without commercial or international support. The arguments for and against colonisation of the Moon are likely to hot up as the Asian countries enter the space race. India and China have plans to launch space probes in the next 12 months and Japan has already launched a spacecraft to the moon.

On 14 September Japan launched its Selenological and Engineering Explorer (SELENE for short) from its Tanegashima Island spaceport off the country’s south coast. Better known by the Japanese by its nickname “Kaguya” (for a mythical princess that visited the Moon) the three ton craft is powered by a Mitsubishi H-IIA rocket, the 3 ton rocket. It will orbit the Earth twice before setting off on a two week trip to the Moon. Expected to arrive in a Moon orbit by 3 October, Selene will map and analyse the satellite’s surface, interior and gravitational field.

China will follow suit when it launches Chang’e 1 before the end of the year. Named for the Chinese goddess of the Moon, it will be the first phase of China’s ambitious lunar program. It will be launched before the end of this year. Chang’e 1 represents the “orbiting” phase of the Chinese program and will be followed by a “landing” phase in 2012 and a “returning” phase in 2017. A fourth “manned” phase remains off the agenda for now.

India will also launch its Chandrayaan-L lunar probe in early 2008. And the US’s traditional space rival Russia should not be discounted either. Although their program has been impoverished since the end of the Soviet Union, in 2006 the Duma (parliament) voted a 33 percent increase for Roscosmos, the Russian Space Agency. The will bring its budget, including income from the sale of launch services, to $1.7 billion a year. That is serious money and has given Russia the opportunity to consider returning to the Moon, where no cosmonaut has yet to land. It plans a permanent research base by an ambitious 2012.

But as NASA’s Griffin hinted in his IAC speech, private enterprise will play a large part in all future endeavours. Google have offered $20 million to someone who can send a robotic rover to the moon and beam back a gigabyte of data of the trip. But Google have placed a time limit on the prize in an incentive to speed up the race. It drops to $15 million in 2012 and expires altogether in 2014.

The moon has many attractive properties that would attract private investment but perhaps the most precious of these is Helium 3. Helium 3 is a light isotope of helium with two protons and one neutron. This configuration is rare on Earth but is abundant on the Moon. Its value to an energy hungry world is as a fusion power source. Its major advantage is that it is not radioactive. Some scientists estimate there is about 1 million tons of helium 3 on the moon, enough to power the world for thousands of years. Gerald Kulcinski, has grand ambitions for the isotope. The Director of the Fusion Technology Institute (FTI) at the University of Wisconsin said Helium 3 could be a cash crop on the Moon. "Today helium 3 would have a cash value of $4 billion a ton”, he estimates. "When the moon becomes an independent country, it will have something to trade."

The Hunt for New Earth

The search for life in the universe began a new phase on Wednesday in Kazakhstan with the launch of Corot, the French space telescope. Corot's role will be to seek and find small rocky planets which have a similar size and composition to that of our own Earth. The European Space Agency (ESA) says that's about as difficult as detecting a candle burning next to a lighthouse from a distance of 1000 kilometres.

Corot is an acronym of “COnvection ROtation and planetary Transits” but the name is also a passing nod to the great French 19th century landscape painter Jean-Baptiste Camille Corot. The spacecraft’s mission will be to look for rocky worlds about twice the size of Earth that lie in what space scientists call habitable zones. These are the regions of space in each solar system where heat from the nearest star is neither too hot nor too cold to sustain liquid water which scientists consider the holy grail for sustaining life. Any planets found by Corot will be studied intensely by future missions scheduled for the next decade. Scientists are hoping to gain a better understanding how planets form and how common other earth-like planets may be.

The study of planets outside our solar system began in 1995 when Swiss astronomer Michel Mayor discovered 51 Pegasi b, a gassy giant that orbits the star 51 Pegasi in the Pegasus constellation. Pegasi’s discovery opened the floodgates. In the last 12 years astronomers have found over 200 “exo-planets” which are all gas giants similar to Jupiter. However the problem with all of these planets is that they have no surface and are therefore incapable of supporting life. Small planets are too difficult to detect from Earth due to our atmosphere which blurs the picture. The Hubble Space Telescope was launched to gain clearer pictures of outer space. But Hubble’s mission is to search for stars in deep space not to look for tiny planets in our immediate neighbourhood. Hence Corot.

The Corot space telescope project is led by CNES (Centre National d'Études Spatiales - the French Space Agency) in conjunction with several European partners and Brazil. The spacecraft is equipped with a 27 cm diameter afocal telescope and a camera sensitive to tiny variations of the light intensity from stars. A Russian rocket lifted the satellite into a circular polar orbit with an altitude of 827 km where it will stay for the next two and half years. It will observe perpendicular to its orbital plane, meaning there will be no Earth eclipse (properly called an “occultation”), allowing 150 days of continuous observation. Beyond 150 days, the Sun's rays can interfere with the results.

Corot will focus on two parts of the universe which are relatively close to Earth. The first is the centre of our own galaxy, the Milky Way; the other is the constellation Orion. Like Hubble, it will measure how much light comes from a star. Corot will be hoping to spot a small eclipse that would indicate a planet crossing in front of the star. So Corot will only be able to indirectly detect the presence of a planet. But it is an important stepping stone in the effort to find habitable, Earth-like planets around other stars.

To verify light variation from a star found by Corot, we will have to wait until Project Darwin, the ESA most ambitious long-term adventure. Darwin is scheduled to launch in 2015 and will comprise of at least four separate components. There will be three, or possibly more, space telescopes, each at least 3 metres in diameter, and another spacecraft will serve as a communications hub. The multiple crafts will be placed in an orbit about 1.5 million kilometres from the Earth. Darwin will require telescope of roughly 30 metres in size and this is way beyond the current limits of technology. By comparison Hubble is barely 2.3 metres. Scientists are using a technique known as interferometry first developed in the 1950s. Inferometry uses a number of smaller telescopes and combines their individual signals to mimic a much larger telescope. The technique will be applied to the infrared telescope to be used by Darwin. It will have a second benefit in that it will cut out the blinding light from the nearby star.

NASA is also planning a mission similar to Darwin. Called the Terrestrial Planet Finder (TPF) it plans to study all aspects of planets outside the solar system. There is no planned launch date at this time and NASA may well decide to combine this project with Darwin. As the 2001 review which recommended the TPF said “"The discovery of life on another planet is potentially one of the most important scientific advances of this century, let alone this decade, and it would have enormous philosophical implications.”

Corot is the first small step to this discovery.

Squirting guns on Mars

The scientific community is digesting the consequences of yesterday’s discovery of water sources on Mars. NASA’s Mars Exploration Program lead scientist Michael Meyer said the latest evidence appears to reveal recent water flow on the surface of the planet. Scientists examined photos sent by Global Surveyor and compared them with those taken seven years ago in the same spot. They observed water had flowed through the 20 new craters they detected recently. NASA say water may have come up from under the surface and flowed long enough to have left traces. However water would quickly freeze at the surface of the cold planet.

Mars has always excited watchers with the possibility it may contain forms of life. 19th century telescopes allowed for detailed study of the planet. Astronomers saw icecaps at the poles and light that changed colour with the seasons. Some saw the grooves in the planet and imagined they were irrigation channels of liquid water. In 1877 Italian astronomer Giovanni Schiaparelli used a new high resolution telescope to produce the first detailed map of Mars. These maps contained features he called canali. The word meant channels but was mistakenly translated into English as canals.

The American self-funded astronomer Percival Lowell was fascinated by Sciaparelli’s theories and spent much of his life studying Mars from his massive observatory at Flagstaff, Arizona. Lowell was convinced the Martian channels were irrigation canals built by a highly intelligent civilisation. His work captured the imagination of the general public and the idea of canals spread under the influence of the science-fiction of Jules Verne and H.G. Wells.

Not everyone was fooled by Lowell’s enthusiasm for the canals. In 1903, the sceptical English astronomer Edward Maunder conducted visual experiments using marked circular disks which led him to the conclusion the canals were an optical illusion. He also said the lack of temperature-equating winds and low mean temperatures meant Mars could not support Earth-like life. It took another sixty years for Maunder to be proved right.

The first flyby by a spacecraft finally dispelled the idea of canals forever. In 1965 Mariner 4 passed over the planet at an altitude of almost 10,000kms above the surface. It took almost eight months to reach its destination and carried a television camera. It returned 22 television pictures which revealed a vast, barren wasteland of craters on a rust-coloured sandy surface. There were no canals. After Mariner 4, scientists accepted the hypothesis that Mars was a dead planet.

Viking 1 was the next Earth expedition to Mars. Launched in 1975, it was planned to land on Mars to celebrate the bicentennial July 4 the following year. However the landing was delayed after the primary site was deemed too rough by NASA. It was followed by Viking 2 three months later. They scooped up samples of the soil and looked for by-products such as oxygen and carbon dioxide. But neither craft found any evidence to support life. However a seismometer aboard Viking 2 did record a marsquake.

Another 20 years would pass before the Pathfinder probe bounced onto the planet with airbags inflated to soften the landing. Aboard the Pathfinder was Mars’ first rover, the Sojourner. Sojourner contained an on-board camera which relay signals back to the base and then on to Earth. It discovered Mars has a crust, mantle, and core, with the heavier elements nearer to the centre. It also encountered evidence of wild weather in the shape of 200 kph winds which had sandblasted rocks.

Meanwhile back on Earth, scientists discovered a Martian meteorite in Antarctica. This rock with the prosaic name of Alan Hills 84001 was scooped off Mars 16 million years ago and after a long trip in space landed on Earth a mere 13,000 years ago. Of most interest were small worm-shaped structures called chondrules the scientists found on the rock. These structures formed billions of years ago when water seeped into the rock. Inside the chondrules were what appeared to be fossilised worms, organic material, and another possibly life-based compound called "magnetite." They declared this might be a form of primitive Martian bacteria, proving life exists on Mars. These findings were later disputed and most scientists now believe the rock has been “contaminated” by its recent life on Earth.

The water discoveries were made by the planet’s most recent visitor. Launched on November 7, 1996, the Mars Global Surveyor is now orbiting Mars. Between 1999 and 2001, it has mapped the entire surface of the planet. It discovered the upper half of the northern hemisphere of Mars was almost entirely flat. Scientists theorised oceans may have flattened it, as the only areas on Earth that are this flat are at the bottoms of deep oceans. In November this year NASA lost contact with the spacecraft after commanding it to adjust its solar panels. The craft’s final gift to NASA was the photos of two craters called Terra Sirenium and Centauri Montes which appear to show the presence of water on Mars within the past seven years.

These images of gullies on Mars show evidence of new flows and deposits. They seem to indicate explosive events in which some form of water burst from crater walls and ran down their slopes. Researchers are talking about a "squirting gun" theory. Mars expert Phil Christensen from Arizona State University said "there is evidence to say, yes, there is subsurface water" but it will take years to prove or disprove”. He went on to say, "ten years ago, Mars scientists were talking about water billions of years ago. Now we can honestly talk about liquid water on the surface today."

Eyes on Titan

Voyager 1 is our farthest missile. Scientists reckon it is now almost ten billion miles away and officially out of the solar system, a resident of stellar space. Way back in 1980 it was our first close-up visitor of Saturn. While there, it examined the remarkable moon of Titan. It found Titan to be the first moon in the solar system with an atmosphere. Scientists now know that Earth and Titan are cousins or possibly even lovers that exist in sweet spots of the solar system. They know that wind, rain, volcanism and tectonic activity all occur on Titan. There are rivers. Titan is the second largest moon in the solar system. It’s bigger than our moon and smaller than the earth. But because Titan is so far away from the sun it’s a icy world. The sun lies about 1.3 billion kms away. That makes it ten times further away from the star than we are. It’s so cold that it is possibly perfect for methane to form rivers which erode the landmass of ice.

So as a laboratory Titan will be cold and slow going. Nothing much quickly occurs at -180 degrees. The temperature is so low that is easier to express in Kelvin: 94K. But despite these bitter conditions, the scientists who looked after Voyager saw that the best thing about the entire mission was the discovery of the atmosphere on Titan. It was obvious therefore that if we were going to the expense of sending another probe in that general direction then Titan was obviously the place to go. The NASA called this probe Cassini. Giovanni Domenico Cassini was an astronomer. He was born in the Republic of Genoa in 1625. He died in the capital of death, Paris, in 1712. Cassini shares the credit with Robert Hooke as Jupiter’s great spot spotters. On Saturn he was the first to see four moons of Saturn and discovered the Cassini Division, rings of Saturn. It is appropriate that the next visitor to these regions be named after him

Aboard American Cassini bound for Saturn would be a smaller European probe bound for Titan. Something had to go through the atmosphere and check it out. The Europeans called their probe Huygens. Christiaan Huygens was a Dutch contemporary of Cassini. Huygens was younger than Cassini but died before him. Huygens was first and foremost a mathematician. His main claim to fame was the invention of the splendid pendulum clock which was a reliable measure for the fourth dimension, time. But he was also an astronomer and it was he who first observed Titan in 1655.

Together Cassini-Huygens were a sailing ship and its boats. Cassini would get us to the coast but Huygens would get us ashore. That was the theory anyway. The idea dates to 1982, when the European Science Foundation and the American National Academy of Sciences got together to investigate future missions together. But not much concrete was done on it in the years to follow. The idea got wings in 1987 when Sally Ride, the first American women in space four years earlier, wrote a report for NASA. NASA commissioned the Ride Report to outline a new forward-thinking strategy for the agency. It proposed four areas of study: 1. Earth and the Space Station 2. Exploration of the Solar System 3. Outpost on the Moon and 4. Humans to Mars. As part of point 2. the idea of Cassini around Saturn was dusted off the plans and advised to go with the Europeans so that Huygens could be landed on Titan.

Cassini-Huygens needed to get to Saturn as quickly as possible. It was decided that the perfect planetary alignments of the late 1990s were ideal for providing the fuel necessary to get there. And so it took off in 1997 appropriately on a Titan rocket, the biggest on Earth. It set off in the direction of nearby Venus. It would get two almighty shakes of its gravity by passing around the planet twice. Then, incredibly the plan called for a return trip home to get the benefit of our sling shot effect. Cassini-Huygens bounced off us in August 1999 and the danger of a very fast Earth-bound missile, capable of scoring a vast own goal, passed. That wasn’t the end of its mathematical manoeuvres however. Saturn is a long way from earth and it was time for a mega-swing off Jupiter by twirling once around the daddy planet. The alignment and the maths worked. The mother ship arrived in the waters of Saturn’s orbit just in time for the start of the financial new year on July 1, 2004 some seven years.

On Christmas Day that year Huygens left Cassini and aimed for Titan and landed softly on a planetary plain three weeks later. The pictures it sent back were startling and seemed eerily familiar to photo shots on Earth. Scientists had speculated that conditions on Titan resemble those of early Earth, though at a much lower temperature. But now Huygens evidence is showing volcanic activity and suggests that temperatures are probably much higher in hotbeds, perhaps even enough for liquid water to exist. Titan's surface is relatively smooth. It has possibly been eroded by liquid methane. But the weight of evidence coming from this mission is that Titan is even more interesting a place than when we didn’t know what was under the atmosphere. It is looking increasingly like the second most interesting place in the solar system. Only the other sweet spot,our own astonishing planet, has more variety.

Earth's love affair with Titan has just begun.

the Solar System gets busier

A long-standing fact beloved of school-children across the world is about to change. Ever since American astronomer Clyde Tombaugh discovered Pluto in 1930, it has been commonly understood that the Solar System contains 9 planets. In order of distance from the Sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto (although Pluto occasionally goes nearer to the Sun than Neptune due to its eccentric orbit). However, that list is about to grow. On August 16, the International Astronomical Union (IAU) announced that it is planning to add three new members to the exclusive club of large celestial objects orbiting our Sun.

The additions come after the organisation concluded two years of work defining the difference between "planets" and the smaller "solar system bodies" such as comets and asteroids. If the new definition is approved by the astronomers gathered at the triennial IAU General Assembly in Prague (14-25 August 2006), the Solar System will include 12 planets, with more to come. These will be the 8 closest planets to the Sun, the largest asteroid (Ceres) and three remote ‘plutons’. This new category contains Pluto itself, its erstwhile moon and now double planet Charon and the provisionally sexy-named 2003 UB313. Plutons are distinguished from classical planets in that they reside in highly tilted orbits around the Sun that take longer than 200 years to complete (i.e. they orbit beyond Neptune). The draft "Planet Definition" Resolution will be discussed and refined during the General Assembly and then it will be presented for voting on 24 August.

The word "planet" comes from the Greek word for "wanderer”. There is no formal definition for the term but it is generally considered to be a relatively large mass of accreted matter in orbit around a star. Astronomers also drew a distinction between planets, and large asteroids (sometimes confusing called minor planets). With a diameter of almost a thousand kilometres, Ceres, discovered by an Italian monk in 1801, is by far the largest of the asteroids. For the next fifty years it was classified as a planet but once its true size was known, it was reclassified as an asteroid. Ceres has remained an asteroid for the last 150 years.

But the meaning of the word planet has come under increasing scrutiny due to recent discoveries. Pluto was initially added to the list of 8 planets because it was believed to be as big as Earth. Later its diameter was measured to be just 18% of Earth’s. Pluto is smaller than the Moon which is 25% of Earth’s diameter. From the 1990s onwards, astronomers became aware of a vast population of small bodies orbiting the sun beyond Neptune. But the trouble really started with the discovery of 2003 UB313. As the name would suggest it was discovered in 2003 by a team at Mt Palomar observatory in San Diego. Dubbed “Xena” by its discoverers, it is currently classified as a “Scattered Disk Object” but because it is slightly larger than Pluto and even has its own moon, many have argued that it too should be given planet status. Xena is three times further away from the Sun as Pluto.

The discovery drastically heated up the debate over how to define a planet. Some astronomers claim Pluto is just an overgrown Kuiper-belt object and there are really only eight planets. However, if the new definition is accepted, then the list will rise quickly from 12. Currently a dozen other "candidate planets" are listed on IAU's "watchlist" which keeps changing as new objects are found and the physics of the existing candidates becomes better known. The number could rapidly accelerate to the thousands as objects in the Kuiper belt are identified by prospective planet-finders. This should make an interesting dilemma for those attempting to stay within the current naming convention: all planets must be named after Roman gods.

The days of an easily memorised and numbered Solar System are itself numbered.