Europe plans asteroid sample grab
By Jonathan Amos
Science reporter, BBC News
European scientists and engineers are working on a potential new mission to bring back material from an asteroid.
The venture, known as Marco Polo, could launch in the next decade, and would be designed to learn more about how our Solar System evolved.
The plan is to select a small asteroid - less than 1km across - near Earth and send a spacecraft there to drill for dust and rubble for analysis.
Mission plans are being worked on by UK Astrium and OHB in Germany.
Both satellite manufacturers have been asked to undertake a feasibility study, to assess the type of spacecraft architecture that would be needed to carry out the project.
Esa says the mission could fly towards the end of the next decade
A final decision on whether to approve the mission will be made by the European Space Agency (Esa) in a few years' time. The mission would launch towards the end of the next decade, in about 2017.
Asteroids are the debris left over from the formation of the Solar System about 4.6 billion years ago.
Asteroids are the rubble left over after the planets formed
Rosetta probe makes asteroid pass
Studying their pristine material should provide new insights about how the Solar System came into being and how planets like Earth evolved.
"We'll be looking at the best solution for getting there and back," UK Astrium's Dr Ralph Cordey told BBC News.
"We've got to look at all elements of the mission - how we would design the mission, how to design the trajectory to one of a number of possible asteroids, how to optimise that so we use the smallest spacecraft, the least fuel and the smallest rocket."
Marco Polo might work like this:
• After the launch on a Soyuz rocket from Europe's Kourou spaceport, a propulsion unit would take the mission out to its target asteroid
• The main spacecraft unit would undertake a remote-sensing campaign, gathering key information on shape, size, mass and global composition
• It would then attempt to land, drilling a few cm into the surface. Up 300g of dust and pebbles would be stored away in a sealed capsule
• After lifting off the asteroid, the spacecraft would put itself on a homeward trajectory, releasing the capsule close to Earth for a re-entry
• The capsule would land without parachutes. It would be opened in a clean facility to ensure there was no Earth contamination
Marco Polo would map the asteroid as well as grabbing a sample
Esa has an exploration roadmap for the missions it wishes to conduct in the coming years. Marco Polo is being considered under its Cosmic Visions programme, and is one of a number of competing ideas in a class of missions that could cost in the region of 300 million euros.
It is quite possible that Marco Polo, if approved, could be undertaken in partnership with Japan.
Sample return missions are of significant interest to scientists. Although in-situ measurements provide remarkable insights, so much more would be learnt if materials were brought back to Earth laboratories, where the full panoply of modern analytical technologies can be deployed.
The small return capsule would be released just prior to re-entry
An asteroid sample return mission would have huge scientific merit in its own right but it would also help develop the technology needed for the more challenging task of getting down and up from a large planetary body that has a much bigger gravitational pull - such as Mars.
Not that getting down on to a small, low-gravity body is easy. The wrong approach could crush landing legs or even result in the vehicle bouncing straight back off into space.
Such problems were amply demonstrated by the recent Japanese attempts to grab samples off the surface of Asteroid Itokawa.
It is still not clear whether Japan's Hayabusa spacecraft managed to capture any material and the probe's return to Earth is still haunted by uncertainty.
The Americans deliberately crash-landed their Near-Shoemaker probe on to Asteroid Eros at the end of the spacecraft's mission in 2001.
They have also sent the Dawn spacecraft to rendezvous with Asteroid Vesta in 2011 before going on to visit Asteroid Ceres in 2015. This is a remote-sensing venture, not a sample return attempt.
There is even feasibility work going on in the US space agency to look at how astronauts could be sent on an asteroid mission one day.
vrijdag 19 september 2008
zondag 14 september 2008
Breaking the ice
37,552 tourists visited Antarctica between 2006 and 2007
A new radar satellite imaging system is helping ships navigate safely through sea ice in one of the planet's last great wildernesses, Antarctica.
More tourists than ever before are visiting the great white continent.
The International Association of Antarctica Tour Operators shows that 37,552 tourists visited Antarctica between 2006 and 2007, with the majority arriving by sea.
However, the water around the continent is a dangerous place, as the passengers on board the M/S Explorer found out last year when the liner hit and iceberg and sank in the Antarctic.
With more people visiting and the concomitant increase in the number of ships, it is becoming increasingly important to find ways of navigating safely and avoiding future collisions.
The Antarctic Polar View project is using satellites to map the sea ice, to help ships find the best way through to the vast White Continent.
Anna Lacey went to the British Antarctic Survey in Cambridge to find out about a new project that's using satellite technology to improve navigation in the Southern Ocean for the BBC World Service's Digital Planet programme.
Pretty dangerous
"There are very large lumps of heavy ice in the water, that might look pretty in white with penguins dancing on top of it, but trust me you don't want to hit it very fast with a ship," said Andrew Fleming from the British Antarctic Survey who is leading the research.
"If you do, you are going to damage your ship and therefore navigating through it is a problem, not only in terms of the safety of the ship but in terms of the speed of the ship and the efficiency of the ship.
"So, you don't want to spend an excessive amount of time going through an area of very thick ice when you could be taking a quicker and therefore cheaper route," he added.
Antarctica may look beautiful but it can be a dangerous place
The quickest way to travel through the Antarctic is via clear water channels. However, finding these routes is a difficult task.
"The area we're dealing with is absolutely enormous, the only way of monitoring that area of ocean effectively is using satellites.
"We use a satellite called ENVISAT, which is a radar satellite that picks up differences in ocean surface roughness and that allows us to see the difference in open water and the sea ice," said Mr Fleming.
The radar allows the team to see straight through the clouds down to the surface of the sea. With detailed images, it's even possible to see the cracks in sea ice, which can lead to dangerous ice falls.
Robb Clifton, who works for the Australian Antarctic Division as a voyage leader, is someone who knows how useful these satellite images are in practice.
"Wherever possible, we would use helicopters quite a lot and put them up in the air to map the ice and look for where we might find what we call 'leads', you know which are large areas of clear water, that the ship might be able to move through," he said.
"But it was certainly a much more difficult, time-consuming operation," he added.
Making the most of it
Although the Antarctic Polar View Project is hugely useful, there are some ways in which it could be improved.
"We can't yet determine the thickness of the sea ice but one of the science programmes that we were doing last summer was looking at doing some of that work using satellites as well and that's going to be quite an exciting development," said Mr Clifton.
The maps of the sea are coloured in various shades of grey, with the dark areas being the smooth open water and the light areas identifying the textured areas of sea ice.
However, taking the image is only the first step as it then has to be sent to the ship.
"Internet connections in the Antarctic and on ships are notoriously poor and that has meant that we have ended up cropping the image, compressing it a lot and losing a lot of the detail in the image as a result," said Mr Fleming.
Internet connections in the Antarctic and on ships are notoriously poor
Andrew Fleming
"So, we have to find a way of getting imagery that is very large - down that very narrow bandwidth to the users on the ship," he added. One way they're doing this is by compressing the images into a format known as JPEG2000.
"JPEG2000 allows us to compress the image a lot more and secondly it allows us to preserve the geographic position of the image, so it knows where the image is and allows us to position it on a map.
"On the other hand we are using a system that now allows us to deliver that image in bite size chunks.
"What we deliver first of all is just a low resolution image of the entire area and then the user can choose what he wants detail of, zoom into that area and then our system only delivers the higher resolution information of that particular area," said Mr Fleming.
Although the system is fairly new, it's already making an impact for those who sail the seas.
"I mean we now know fairly well the kind of sea ice conditions we are likely to encounter, so it's a fantastic and very easy to use and easy to interpret system that we just run off a laptop on the bridge of the ship," added Mr Clifton.
37,552 tourists visited Antarctica between 2006 and 2007
A new radar satellite imaging system is helping ships navigate safely through sea ice in one of the planet's last great wildernesses, Antarctica.
More tourists than ever before are visiting the great white continent.
The International Association of Antarctica Tour Operators shows that 37,552 tourists visited Antarctica between 2006 and 2007, with the majority arriving by sea.
However, the water around the continent is a dangerous place, as the passengers on board the M/S Explorer found out last year when the liner hit and iceberg and sank in the Antarctic.
With more people visiting and the concomitant increase in the number of ships, it is becoming increasingly important to find ways of navigating safely and avoiding future collisions.
The Antarctic Polar View project is using satellites to map the sea ice, to help ships find the best way through to the vast White Continent.
Anna Lacey went to the British Antarctic Survey in Cambridge to find out about a new project that's using satellite technology to improve navigation in the Southern Ocean for the BBC World Service's Digital Planet programme.
Pretty dangerous
"There are very large lumps of heavy ice in the water, that might look pretty in white with penguins dancing on top of it, but trust me you don't want to hit it very fast with a ship," said Andrew Fleming from the British Antarctic Survey who is leading the research.
"If you do, you are going to damage your ship and therefore navigating through it is a problem, not only in terms of the safety of the ship but in terms of the speed of the ship and the efficiency of the ship.
"So, you don't want to spend an excessive amount of time going through an area of very thick ice when you could be taking a quicker and therefore cheaper route," he added.
Antarctica may look beautiful but it can be a dangerous place
The quickest way to travel through the Antarctic is via clear water channels. However, finding these routes is a difficult task.
"The area we're dealing with is absolutely enormous, the only way of monitoring that area of ocean effectively is using satellites.
"We use a satellite called ENVISAT, which is a radar satellite that picks up differences in ocean surface roughness and that allows us to see the difference in open water and the sea ice," said Mr Fleming.
The radar allows the team to see straight through the clouds down to the surface of the sea. With detailed images, it's even possible to see the cracks in sea ice, which can lead to dangerous ice falls.
Robb Clifton, who works for the Australian Antarctic Division as a voyage leader, is someone who knows how useful these satellite images are in practice.
"Wherever possible, we would use helicopters quite a lot and put them up in the air to map the ice and look for where we might find what we call 'leads', you know which are large areas of clear water, that the ship might be able to move through," he said.
"But it was certainly a much more difficult, time-consuming operation," he added.
Making the most of it
Although the Antarctic Polar View Project is hugely useful, there are some ways in which it could be improved.
"We can't yet determine the thickness of the sea ice but one of the science programmes that we were doing last summer was looking at doing some of that work using satellites as well and that's going to be quite an exciting development," said Mr Clifton.
The maps of the sea are coloured in various shades of grey, with the dark areas being the smooth open water and the light areas identifying the textured areas of sea ice.
However, taking the image is only the first step as it then has to be sent to the ship.
"Internet connections in the Antarctic and on ships are notoriously poor and that has meant that we have ended up cropping the image, compressing it a lot and losing a lot of the detail in the image as a result," said Mr Fleming.
Internet connections in the Antarctic and on ships are notoriously poor
Andrew Fleming
"So, we have to find a way of getting imagery that is very large - down that very narrow bandwidth to the users on the ship," he added. One way they're doing this is by compressing the images into a format known as JPEG2000.
"JPEG2000 allows us to compress the image a lot more and secondly it allows us to preserve the geographic position of the image, so it knows where the image is and allows us to position it on a map.
"On the other hand we are using a system that now allows us to deliver that image in bite size chunks.
"What we deliver first of all is just a low resolution image of the entire area and then the user can choose what he wants detail of, zoom into that area and then our system only delivers the higher resolution information of that particular area," said Mr Fleming.
Although the system is fairly new, it's already making an impact for those who sail the seas.
"I mean we now know fairly well the kind of sea ice conditions we are likely to encounter, so it's a fantastic and very easy to use and easy to interpret system that we just run off a laptop on the bridge of the ship," added Mr Clifton.
No aid for next-gen network firms
Amsterdam's ambitious internet plan
There is no need to use public money to bankroll next-generation broadband in the UK, says a report.
The six-month long review of the UK's readiness for high-speed net access said the case for government intervention was "weak".
The review said there were "promising signs" that the market was already delivering high-speed broadband.
But, it said, the government must oversee initiatives that will smooth the route to high-speed access.
Speed boost
"There is little evidence that in the short term the UK is going to suffer from the lack of an extensive next generation access network," said review author Francesco Caio as he unveiled his conclusions.
Rather than hand over public money to telecoms firms that will be laying fibre-optic cables to homes and businesses, Mr Caio said the government should ensure the regulatory regime encourages firms to take the financial risks themselves.
Next-generation broadband would boost the speed of connections to 100 Megabits per second (Mbps) and beyond.
In the UK the average speed of high-speed fixed line net access is 3-4 Mbps - but this fluctuates widely depending on where people live. Telecoms firms will boost speeds by replacing ageing copper cables with fibre that use light to carry data.
But this city is betting that it will be cheaper to get into the fast lane now, rather than wait and see the costs of the labour to dig up all those roads - and canals - rise later.
Rory Cellan-Jones
dot.life blog
Japan tops world broadband study
The cost of putting in a basic next-generation broadband is likely to top £5bn according to analysis by the Broadband Stakeholder's Group. Laying cables to every home and business could push costs to £28bn.Mr Caio said BT's plan to spend £1.5bn on laying fibre and Virgin's plans to improve its network were "promising signs" that the UK was on track to update its broadband infrastructure.
However, a report from net firm Cisco suggests that the UK's net infrastructure is already falling short of what users want to do with it. Cisco drew up a net quality index which looked at whether the infrastructure was reliable enough to become the bedrock for existing or future web-based services and applications.
"Notably the UK, Spain and Italy didn't cut that threshold, even for today's applications," said Fernando Gil de Bernabe, a spokesman for Cisco.
The government's role in next-generation broadband should be to support local groups keen to signal their interest in getting high-speed access. It should also relax rules that stop high-speed access being offered via overhead and work with building firms to ensure all new build homes have next-generation access.
Antony Walker, head of the Broadband Stakeholder Group, said although the report ruled out substantial subsidies it did charge the government and regulator Ofcom with significant duties to make sure next-gen broadband took off.
"The government needs to come off the fence about next-generation broadband and be very clear that it thinks it is of real, fundamental importance to the UK economy for the next 5-10 years," said Mr Walker.
The government needed to adopt a leadership role to create the right environment for next-gen broadband to take off, he added.
It was very unlikely that any single telecoms firm would be wiring up the whole of the UK for fibre. Instead, he said, different firms would upgrade different parts of the UK.
"Making sure that patchwork fits together seamlessly - that's where government and Ofcom have a role to play," he said.
Also, he said, the government and Ofcom should get behind the local initiatives that will try to take high-speed broadband to rural areas. Backing such schemes would help stimulate demand in areas where some firms may have been reluctant to upgrade cables, he said.
"Demand stimulation initiatives are going to be very important and in many areas will make a significant difference," he said.
The review was kicked off on 22 February 2008 by Business and Competitiveness Minister Shriti Vadera.
It aimed to find out what the government should do to ensure next generation broadband technology does get rolled out in the UK in a timely fashion.
The review was tasked with discovering what, if any, barriers existed that would stop firms taking on the financial risk of investing in the technology.
The government said it would respond to the review and its recommendations in "due course".
Amsterdam's ambitious internet plan
There is no need to use public money to bankroll next-generation broadband in the UK, says a report.
The six-month long review of the UK's readiness for high-speed net access said the case for government intervention was "weak".
The review said there were "promising signs" that the market was already delivering high-speed broadband.
But, it said, the government must oversee initiatives that will smooth the route to high-speed access.
Speed boost
"There is little evidence that in the short term the UK is going to suffer from the lack of an extensive next generation access network," said review author Francesco Caio as he unveiled his conclusions.
Rather than hand over public money to telecoms firms that will be laying fibre-optic cables to homes and businesses, Mr Caio said the government should ensure the regulatory regime encourages firms to take the financial risks themselves.
Next-generation broadband would boost the speed of connections to 100 Megabits per second (Mbps) and beyond.
In the UK the average speed of high-speed fixed line net access is 3-4 Mbps - but this fluctuates widely depending on where people live. Telecoms firms will boost speeds by replacing ageing copper cables with fibre that use light to carry data.
But this city is betting that it will be cheaper to get into the fast lane now, rather than wait and see the costs of the labour to dig up all those roads - and canals - rise later.
Rory Cellan-Jones
dot.life blog
Japan tops world broadband study
The cost of putting in a basic next-generation broadband is likely to top £5bn according to analysis by the Broadband Stakeholder's Group. Laying cables to every home and business could push costs to £28bn.Mr Caio said BT's plan to spend £1.5bn on laying fibre and Virgin's plans to improve its network were "promising signs" that the UK was on track to update its broadband infrastructure.
However, a report from net firm Cisco suggests that the UK's net infrastructure is already falling short of what users want to do with it. Cisco drew up a net quality index which looked at whether the infrastructure was reliable enough to become the bedrock for existing or future web-based services and applications.
"Notably the UK, Spain and Italy didn't cut that threshold, even for today's applications," said Fernando Gil de Bernabe, a spokesman for Cisco.
The government's role in next-generation broadband should be to support local groups keen to signal their interest in getting high-speed access. It should also relax rules that stop high-speed access being offered via overhead and work with building firms to ensure all new build homes have next-generation access.
Antony Walker, head of the Broadband Stakeholder Group, said although the report ruled out substantial subsidies it did charge the government and regulator Ofcom with significant duties to make sure next-gen broadband took off.
"The government needs to come off the fence about next-generation broadband and be very clear that it thinks it is of real, fundamental importance to the UK economy for the next 5-10 years," said Mr Walker.
The government needed to adopt a leadership role to create the right environment for next-gen broadband to take off, he added.
It was very unlikely that any single telecoms firm would be wiring up the whole of the UK for fibre. Instead, he said, different firms would upgrade different parts of the UK.
"Making sure that patchwork fits together seamlessly - that's where government and Ofcom have a role to play," he said.
Also, he said, the government and Ofcom should get behind the local initiatives that will try to take high-speed broadband to rural areas. Backing such schemes would help stimulate demand in areas where some firms may have been reluctant to upgrade cables, he said.
"Demand stimulation initiatives are going to be very important and in many areas will make a significant difference," he said.
The review was kicked off on 22 February 2008 by Business and Competitiveness Minister Shriti Vadera.
It aimed to find out what the government should do to ensure next generation broadband technology does get rolled out in the UK in a timely fashion.
The review was tasked with discovering what, if any, barriers existed that would stop firms taking on the financial risk of investing in the technology.
The government said it would respond to the review and its recommendations in "due course".
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