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Following its loss of contact on 8 April, and a subsequent failure to recover the spacecraft, the European Space Agency (ESA) has formally declared that the Envisat environmental and remote sensing satellite mission is now over. 

Since the failure, engineers and scientists from ESA and Envisat's manufacturer Astrium have struggled to recontact the craft. The attempt at fault finding and recovery even enlisted ground radar and telescopes on Earth and Pleiades imaging satellites in space.  However, in the end all the effort was fruitless. 

Artist's impression of the Envisat spacecraft.  Courtesy: Astrium

Despite the formal ending of the mission, engineers will continue to investigate the failure and carry on with attempts to recontact the craft.  For the time being, an internal power regulator failure or short circuit is suspected of causing the sudden failure of the telemetry and command system or its safe mode solar pointing default procedure; failures that there would normally be no way back from.    

Launched in March 2002, Envisat exceeded its five year minimum design life by over five years.  During its ten year life the spacecraft has yielded valuable Earth monitoring data covering weather, atmospheric and temperature measurements as well as providing optical and infrared imagery.  Concerns remain within the climate change science community that the dataset will now be significantly interrupted until ESA's new Sentinel spacecraft from Europe's Global Monitoring for Environmental Security (GMES) programme, can come online.

 

In early May, teams of rocket enthusiasts were at the Big Range 2012 Launch Campaign in Sutherland, Scotland to hold suborbital high altitude experimental rocketry tests.  The event is a collaboration between the Scottish Aeronautics & Rocketry Association (SARA), UK Rocket Association (UKRA) and AspireSpace. 

 

Of the teams, one from Cambridge University made an attempt at taking the current UK altitude record for an amateur rocket.   The record currently stands at 24,500 feet and the Cambridge hoped to better that by 10,000 feet using a two stage solid fuel rocket using 15kg of ammonium perchlorate - the same fuel that were used by the Solid Rocket Boosters (SRBs) on the Space Shuttle launch system.  The Cambridge team's rocket's light weight structure was made from carbon fibre and red anodised aluminium.  The total mass of the rocket was 40kg.

 

After a one day delay due to ignition failure, the launch and stage separation went well on 3 May.  However, sadly, the team could not tell whether the altitude record had been breached as they could not find the second stage with the altimeter recording system aboard.   The science writer, Dr. Lucy Rogers, who was observing the launch, amusingly commented: "We hope the gamekeeper will come across it sometime."

 

The team was not disheartened however and gained plaudits from rocket experts including James Macfarlane, Chairman of the UK Rocket Association (UKRA) and Director of the rocket research firm Airborne Engineering Ltd:  "I am very impressed with this group. Every problem they have encountered they have designed and built elegant and professional solutions."

 

Given the altitude targets involved, a special NOTAM air traffic warning was issued for the event which is now expected to become an annual gathering.   Next year, the Cambridge University Spaceflight Rocket Team is promising to return with a three-stage rocket capable of reaching 50,000 feet.  

 

 

 

The European Space Agency remains hopeful that it can regain contact with its Envisat Earth observation satellite, which unexpectedly stopped sending data to the ground on 8 April.

Attempts to regain contact have so far been unsuccessful, but the spacecraft - one of the most sophisticated of its type and invaluable in such efforts as quantifying climate change - is in a stable orbit, ESA has determined by optical, radar and laser observation.

But earlier this week France's Pleiades Earth observation satellite passed within about 100km of Envisat and was successfully turned to gather images of Envisat that are being analysed along with ground-based observations to determine whether its solar panels are oriented to the Sun. If they are, ESA says, Envisat may have enough power to have entered a safe mode - and, possibly, enough power for re-establishing communication with Earth.

Information on Envisat's orbit is being provided by the US Joint Space Operations Center. In addition, multiple laser ranging stations on the ground are providing information to verify the stability of the satellite's orbit.

More than 4000 projects in over 70 countries have been supported with Envisat data, and even if contact is regained, many will have been affected by the loss of continuity of data. Should Envisat remain out of contact, a contingency agreement with the Canadian Space Agency will see some of the users assisted by data from its Radarsat.

But in any case Envisat, launched in 2002 with a planned life of five years has already exceeded its expectations. However, its current difficulties make the launch next year of the first in a series of replacements that much more urgent.

These Sentinel satellites are seies being developed for Europe's Global Monitoring for Environment and Security (GMES) programme and will provide the data needed for information services to improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security. ESA describes the Sentinal series missions thus:

Sentinel-1 is a polar-orbiting, all-weather, day-and-night radar imaging mission for land and ocean services. The first Sentinel-1 satellite is planned for launch in 2013.

Sentinel-2 is a polar-orbiting, multispectral high-resolution imaging mission for land monitoring providing, for example, imagery of vegetation, soil and water cover, inland waterways and coastal areas. Sentinel-2 will also deliver information for emergency services. The first Sentinel-2 satellite is planned for launch in 2013.

Sentinel-3 is polar-orbiting, multi-instrument mission to measure variables such as sea-surface topography, sea- and land-surface temperature, ocean colour and land colour with high-end accuracy and reliability. The first Sentinel-3 satellite is planned for launch in 2013.

Sentinel-4 is a payload that will be embarked upon a Meteosat Third Generation-Sounder (MTG-S) satellite in geostationary orbit scheduled to be launched in 2019. Sentinel-4 is dedicated to atmospheric monitoring.

Sentinel-5 is a payload that will be embarked on a MetOp Second Generation, satellite, also known as Post-EPS, to be launched in 2020. Sentinel-5 is dedicated to atmospheric monitoring.

Sentinel-5 Precursor satellite mission is planned to launch in 2015, thereby avoiding data gaps between Envisat (Sciamachy data in particular) and Sentinel-5. This mission will be dedicated to atmospheric monitoring.

Reports in the Russian Novosti Kosmonavtiki website state that the Russian Federal Space Agency is willing to go ahead with Phobos-Grunt 2 after the failure of the original Phobos-Grunt spacecraft in November 2011. The mission will be included in future plans but no date for the launch has yet been set. The original mission was intended to fly to the Martian Moon Phobos, collect some soil samples and return them to Earth.

 

Having previously collaborated on the Extreme Ultraviolet Imaging Spectrometer (EIS) instrument for JAXA's  Hinode (Solar B) mission, and with the UK having provided disaster monitoring imaging via the Disaster Monitoring Constellation (DMC) system after the Japanese earthquake and tsunami in March 2011, Japan and the United Kingdom have announced that they are going to collaborate further on space research.  

During April, the UK Minister for Universities and Science, David Willetts signed an agreement with the Japanese Economy Minister Motohisa Furukawa for greater collaboration on space research and technology,  This is likely to include working on on earth observation technology, such as the NovaSAR  space radar programme or the Disaster Monitoring Constellation (DMC) run by Surrey Satellite Technology Limited

Space Station astronauts are probably more disappointed than we imagined by the delay - from 9 to 23 March - of the European Space Agency's launch of its third Automated Transfer Vehicle robotic supply ship. Named Edoardo Amaldi after the late Italian physicist considered a pioneer of European spaceflight, ATV-3 is loaded with some 2.5t of dry cargo, water and oxygen, in addition to 5.4t of fuel to power itself and "re-boost" the Station to its full altitude. Another 860kg (1,900lb) of fuel will be carried for transfer to the Russian part of the Station.

But now we learn a bit more about that cargo. According to the ATV's builder, Astrium, one of the items the ATV-3 will be carrying is a new ventilator for the European Columbus laboratory, a component that needs regular replacement.

But of much more pressing concern to the astronauts are toothbrushes of different bristle hardness and toothpaste of various flavours - sort of a care package designed to make them feel at home 400km above the ground.

And, they'll also find some Lego Technic sets, part of a range of experiments that NASA is conducting for a special series of lessons for school pupils back on Earth.

Let's just hope the 153 bags containing 1,062 individual items are well labelled, and that the toothpaste and Lego aren't buried too deep in the ATV's hold.

If you're interested in the future of spaceflight, it's worth taking the time to watch this video from The Amazing Meeting (TAM) 2011. Lightly moderated by Phil Plait of the blog Bad Astronomy, the panel features Bill Nye (the science guy), famed astrophysicist Neil deGrasse Tyson, legendary physicist Lawrence Krauss and astronomer Pamela Gay.

At issue is whether human spaceflight is as valuable as robotic probes, and whether or not to go ice fishing on Europa.

It's important to note that although panelists mention the James Webb telescope, the panel took place before the SLS decision.

Don't let anybody tell you the people at Surrey Satellite Technology aren't very serious about what they do - or don't have a sense of humour. Herewith one of the bins at their Guildford headquarters:

The European Space Agency just released this video to show how its Galileo satellite navigation system works. I love the part about how a nanosecond error in the onboard clocks would translate to a 30m error on the ground - but if that error were a second, the position error would amount to 300,000km, enough to leave driver wondering whether they were approaching the house or cruising on the Moon.


The first two spacecraft are due for launch on 20 October, and then ESA will be making a fast-track push to provide near-global coverage in 2014 and, in 2019, a full constellation of 27 spacecraft and three orbiting spares.

Unlike the USA's GPS system, Galileo will be fully under civilian control. The idea is to ensure that Europe is self-sufficient in a technology that is becomming increasingly indispensible. Galileo will also do a better job than GPS at high latitudes, so Nordic Europeans should really notice the difference. Everybody else can be sure sure of continuous service - no worries about the US military degrading the signal in an emergency - and, combined with the ground-based signal enhancement system called EGNOS that went live earlier this year, can get position information accurate to less than 1m. EGNOS signals are free, too, and Brussels is encouraging companies to develop receivers and services to exploit them.

Budget wrangles will have delayed Galileo by seven years by the time coverage goes global in 2014, but it should be well worth the wait. Satnav services are already coming down in price, so the combination of an added layer of reliability and better geographic coverage should make them cheap and easy to use for any conceivable application.