Wilson da Silva

Science journalist, feature writer and editor.

Dec. 24, 1995
Published on: Sunday Age
15 min read
Galileo, the little spacecraft that could

The big space missions of recent history are about to become just that - history. Wilson da Silva reveals how we plan to have fewer bucks for Buck Rogers.

THE wild applause was spontaneous and the tears very real. Twice during that morning on 8 December, hope and anticipation at NASA’s Jet Propulsion Lab could have been dashed in a split second. Instead, history was made.

Mr Jan Ludwinski had worked for 10 years waiting for the moment. “It’s been an incredibly long countdown to Jupiter, “ the chief of mission planning for the Galileo robot spacecraft told The Sunday Age.

“Everything went perfectly, just by the book. We were relieved, but we were also extremely proud.” 

For the first time, a spacecraft had been put into orbit around an outer planet, exactly as calculated by its designers six years before and 3.7 billion kilometres away. For the first time, human beings had sent a probe plunging into the gaseous inferno that is the planet Jupiter.

While the Galileo spacecraft fought the powerful gravity of the giant planet to establish a stable orbit, its detachable probe - a hardy 339-kilogram package of instruments and shielding - struck the gas giant’s turbulent clouds at a speed of 170, 000kmh. It was, for a brief moment, the fastest object ever built, travelling 50 times faster than a rifle bullet.

It descended into a maelstrom like nothing on Earth: winds of 350kmh and atmospheric pressure that, deep below, turns the hydrogen and helium of its clouds into liquid metal. A planet so big it could fit 1400 Earths inside it, that emits enough radiation to kill a human being and fry the average personal computer within minutes.

Once through the worst of it, the probe ditched its shield and sent a message to the mother craft high above, then began collecting data with its six on-board instruments.

Back on Earth, technicians at the Tidbinbilla space tracking station outside Canberra - their radio dishes trained on the morning sky - waited for the signal from Galileo that the probe had survived its fiery fall. This was due at 10am, but nothing came. Via a satellite link to the Jet Propulsion Lab in California, to whom the station was relaying the signals, they watched the faces of their NASA colleagues screw up with tension.

Ten excruciating minutes passed. Then came a solitary radio burst, a signal from Galileo saying it had begun to receive data from the probe.

“Everyone started clapping and shaking hands and slapping each other on the back,” Mr Peter Churchill, director of Tidbinbilla, said of the scene in California. “We were fairly relieved.”

The probe, now trapped by Jupiter’s awesome gravity and committed to its suicide mission, was falling deeper and deeper, transmitting readings to Galileo as it went. It had been designed to survive 40 minutes - it transmitted for 57 before being crushed by the pressure.

The precious data was now recorded in Galileo’s computer banks. But its two-year mission studying the great planet and its 16 moons had only just begun.

“Is this a great day or what?” a beaming NASA administrator, Mr Dan Goldin, asked a press conference broadcast around the world.

IT WAS the bravura of old, not seen at NASA since its moonshot heydays. And Galileo also belonged to an earlier age, a probe conceived in the 1970s, readied for launch in 1982 but, thanks to delays with the space shuttle and the 1986 Challenger tragedy that grounded the fleet, did not fly until 1989.

Along the journey, it had the first close encounter with two asteroids, Gaspra and Ida - large chunks of primordial rock, left over from the creation of the solar system, floating between the planets. The data collected is the most detailed of these plentiful yet little-understood interplanetary wanderers.

It made a flypast of Venus, two of Earth and the dark side of the Moon as it slingshotted its way between planets picking up speed for its Jovian assault.

And last year, Galileo had a grandstand view of the spectacular impact into Jupiter of Comet Shoemaker-Levy, an event obscured from astronomers on Earth as it happened on the dark side of the gas giant.

But Galileo has been teetering on the brink of disaster.

Its large radio antenna refused to unfurl after launch, forcing mission controllers to use the tiny small-gain antenna that could transmit only a thousandth of the data. NASA engineers painstakingly re-programmed the computer as it flew, installing a new operating system that could compress the data and allowed it to achieve 70 per cent of its original goals.

Two months ago, its on-board data storage tape refused to stop rewinding, so the end portion cannot be used lest it snap and cripple the mission. All this in a piece of engineering that cost American taxpayers $1.8 billion to build and operate.

That had come on the heels of the failure of the Mars Observer, a similarly ambitious $690-million NASA spacecraft that fell silent in August 1993, before it had even arrived at its destination.

In an economic climate where there are fewer “bucks for Buck Rogers”, costly programs like these are on the way out, and NASA is designing smaller and leaner missions. It has had to: US President Bill Clinton has proposed slicing its budget by $6.5 billion over five years from 1996.

The US Congress, even more determined to cut the budget deficit, has been squeezing NASA fairly hard: it has a counter proposal that could see NASA slim its workforce by 40,000, and privatise its fleet of five space shuttles.

Ironically, NASA is feeling the heat just as it was learning to do more with less, thanks to Mr Goldin, a former aerospace executive who took the helm in 1992. He has sliced its annual budget by a quarter to $18.7 billion, trimmed 25 per cent from the space shuttle’s operating costs and reduced the managerial bureaucracy by up to 75 per cent in some areas.

NASA's Jet Propulsion Lab control room

At the same time, NASA has a revitalised space program that includes more missions than ever before: next year, two probes - including an automated rover - will be sent to Mars, and a satellite to study cosmic X-rays from space will be launched.

In 1998, it is preparing a series of permanent space probes orbiting Earth to study the environment, another to rendezvous with a massive asteroid, as well as the launch of an advanced astronomy platform for deep space study. It also has plans for a launch in 1999 of a flyby mission to Pluto, the ninth and furthest planet still not visited by spacecraft, and for a floating infrared observatory by 2001.

All this with less staff than NASA had in 1962.

Mr Goldin is therefore peeved at the additional cuts Congress is forcing on him. “Well, maybe they ought to cancel the space program,” he has said. “Then we could all sit in the bleachers and watch the rest of the world go by. Japan’s space budget is increasing.” Japan is indeed spending more on space, in contrast to the European Space Agency (ESA), which has sought to trim its budget.

Russia’s space program had been on the edge of collapse following the dismembering of the Soviet Union, until the West agreed to co-operate with it on planned missions, lessening the chance of space engineers being lured away to Third World missile programs.

Other countries have also had strong space programs. China’s is largely military with a healthy sideline in commercial satellite launches as a way of gaining hard currency. India has an active and burgeoning space program with a budget approaching Russia’s. It is one of the few countries with locally developed weather satellites, has its own locally-built fleet of rockets and has made 16 launches since 1988.

Russia, which holds the world record for the greatest number of launches with more than 4000, has had its former superpower status diminished, and now sells rides to its ageing Mir space station to would-be cosmonauts for $13 million to $20 million a pop.

Canada, Sweden and Brazil have had growing space programs for some years. Australia lags far behind, spending just over $5 million a year, mostly on scientific instrumentation that flies on other countries’ spacecraft and managing space tracking stations. It has lost ground since it became the third nation to launch a satellite from its own soil in 1967. The most memorable event of late was to fly a small ultraviolet telescope aboard the space shuttle some years ago. It has a total space budget that is 3 per cent that of Brazil’s and 5 per cent that of Sweden’s.

But only NASA, the Russians, ESA and the Japanese are really in the space exploration business. And they are co-operating like never before. A prime example is space station Alpha, a $22-billion project to build humanity’s first permanent outpost in space, orbiting just above Earth.

About 100 metres across in its intial stages, and an interior volume of almost two jumbo jets, it is a massive undertaking involving 13 nations and not due for completion until 2002. It will be used for a wide range of experiments, from Earth and stellar observation to the commercial development of new materials.

The recent flights by American and European astronauts on Russian spacecraft, and the docking of a US space shuttle with the Russian Mir space station, have all been in preparation for Alpha. In all, another 10 flights to Mir are expected before the first pieces are assembled in space.

ELSEWHERE, international co-operation is a must for most new missions. The biggest is Cassini, probably the last of the big all-purpose probes that will make its long journey to the ringed gaseous planet Saturn in 1997. It is a joint American- European project that will orchestrate a “slingshot” swing past Venus, Earth and Jupiter before arriving at Saturn in 2004.

It will orbit the planet for four years, launch a European- built probe on a two-and-a-half hour suicide mission into the dense clouds of the most intriguing of Saturn’s 18 moons, Titan. The large moon has a frigid atmosphere with an organic chemistry that may hold clues about the early development of life on Earth. Cassini itself will make 30 close flybys of Titan and at least four other of Saturn’s moons.

The Hubble Space Telescope, the multi-billion dollar optical observatory that has revolutionised astronomy since its faulty optics were repaired in 1993, is already under joint American- European management. And there are plans for a host of medium- sized and smaller missions involving many nations, such as INTEGRAL, a laboratory to study cosmic gamma radiation to be launched in 2001, and Radioastron, a Russian-led project with Australian participation to put a radio-telescope in space.

The Hubble Space Telescope in orbit

So there’s the irony: at a time of budget cutbacks in almost every country with a space program, a record number of space missions are being readied. Dr Louis Friedman, a former Jet Propulsion Lab scientist who is now executive director of the powerful US-based lobby group Planetary Society, said he was hopeful. Although the days of big-budget programs like Galileo and Viking, the probe that landed on Mars in 1976, are past, a lot of good science can still be done.

“There is a lot of activity, and a lot of good missions, “ he told The Sunday Age. “Even four Mars launches . . . don’t begin to add up to the cost of Viking. The jury’s still out on all that will be accomplished in these smaller missions, but I’m quite hopeful.”

Last week, Jupiter passed behind the Sun, plunging Galileo into silence. The planet will not emerge from the other side until February.

When it does, NASA engineers will re-program the spacecraft ahead of its first close-up encounter in June with the Jovian moon of Ganymede, and then Callisto and the very strange Europa in November.

It will be flying 350 times closer than the Voyager probes of the 1980s did, and observe their atmospheres over long periods. Galileo will make flybys of these many times before its batteries die out and it finally crashes into Jupiter thousands of years from now.

Long before that - 7 December, 1997, to be exact - Mr Jan Ludwinski and his Galileo team will be out of a job as the funding runs out. The probe may well be working and transmitting data, if the intense radiation from Jupiter hasn’t fried the instrumentation; but no-one may be around to listen.

WHERE NO MAN HAS GONE BEFORE
A short history of space exploration.

  • 1946: US army fires 60 V2 rockets in near-vertical trajectories, reaching a maximum height of 240km.
  • 1957: Soviets launch Sputnik, first man-made satellite. In December, Sputnik 2 carries dog ‘Laika’ into orbit.
  • 1961: Yuri Gagarin becomes first man in space. President Kennedy commits US to landing on the moon ‘before this decade is out’. Apollo program unveiled.
  • 1964: Mariner 4 photographs surface of Mars.
  • 1969: Neil Armstrong steps on to Moon surface at 12.56pm (AEST) on 21 July.
  • 1973: First US station, Skylab, launched. First close-up photographs taken of Mercury by Mariner 10.
  • 1976: Vikings 1 and 2 land on Mars. Conduct experiments including unsuccessful tests for extra-terrestrial life.
  • 1983: Pioneer 10 becomes the first man-made object to leave solar system.
  • 1986: Challenger shuttle explodes, killing all seven crew. Voyager 2 flies past Uranus.
  • 1990: Hubble space telescope launched.
  • 1995: Galileo space probe starts to orbit Jupiter.