If anyone thought that getting into space was routine now and the danger had been eliminated they should have been completely disabused of that idea over the last few weeks. I have covered some of the private space companies in these posts and so far it has always been good news. In the space of a week Orbital Sciences Corporation's unmanned Antares rocket blew up seconds after launch to the international space station and Virgin Galactic's SpaceShipTwo suffered a catastrophic failure killing the co-pilot and injuring the pilot.

Virgin Galactic

It is only right to start with Virgin Galactic. It is still not clear what exactly happened to cause this accident. Indeed the National Transport Safety Board (NTSB) say their investigation will take a year to report on the cause. Certain facts are known. The vehicle was crewed by two employees of Scaled Composites; the company which built it rather than by employees of Virgin Galactic. The rocket fuel used for this flight had never been flown before. It had been used successfully in ground trials but it is clearly controversial in some circles as "experts" were blaming it on Twitter immediately after the accident including at least one who claimed to have warned Virgin Galactic not to use it.

Because this was a technical test flight there was a lot of telemetry recorded and downloaded. There were six video cameras transmitting live and several flight recorders so those investigating the accident have a very clear picture of what happened on board.

As always the vehicle was flown to 50,000 feet hanging under its carrier plane White KnightTwo. Two seconds after it was released from the plane its rocket engine was fired and everything seemed normal. Several seconds later a catastrophic failure occurred resulting in the vehicle being destroyed and the co-pilot being killed. What is clear is that the two tail stabilisers, normally used at the start of the descent from space, activated which destabilised the aerodynamics. To deploy the stabilisers the pilot has to first unlock it then use another control to activate it. There is video of the co-pilot unlocking the stabiliser but neither pilot used the activation control. Despite this the stabilisers activated. It will be some time before we know the full details but hopefully this accident does not halt the progress of the private space companies. Something like 20 of 700 people have asked for Virgin Galactic to return their deposits and take their name off the waiting list. You have to wonder if these people didn't realise it was dangerous before.

Scaled Composites have made some unique planes and the projects section of their website is well worth a browse if you have any interest in matters aerospace.

Antares

A few days before the Virgin Galactic accident Orbital Sciences Corporation's launch of their Cygnus vehicle on top of the Antares rockets seemed to be going perfectly. It had been delayed from the day before when a ship sailed into the range. Its countdown and lift off went exactly according to plan. Then a few seconds into the flight there was a huge explosion near the bottom of the rocket that left the safety people with no option but to press the self destruct buttons. All rockets manned or unmanned launched from America have a self destruct system. Explosive charges are placed along the length of the rocket and can only be set off if two separate people press their buttons at the same time.

The self destruct was set off to break the rocket into smaller pieces to try and minimise the damage it could cause. Because it was so low it was still full of fuel and that meant lots of flaming wreckage landed on and around the pad causing a lot of damage.

There are a lot of good photos and video of the accident including one showing reporters stationed two miles away running to get away from any debris from the blast. One thing I learned reading about this accident was that people who get access to close viewing of rocket launches in Japan are issued with a hard hat and an armband with a number. The number is only there to help identify the body if things go wrong.

The one piece of good news from this accident is that despite how it looked at the time the pad survived almost intact. Watching live it looked like it would be destroyed.

ISS

Enough bad news. Time for some good news. Imagine 20 years ago someone had told you that a group of countries would get together and construct a space station. Then imagine if you were told that there would be days when 5 vehicles would be docked to it. Sounds like science fiction but it happened. When there is a full crew of 6 on board the station there are 2 Soyuz vehicles docked to it to return them to Earth and to act as temporary life boats when space debris is in the area. There are a range of unmanned delivery vehicles that visit the station now. The major space agencies in USA, Russia, EU and Japan all have unmanned vehicles. Then there is Spacex's Dragon which one day will be a manned vehicle capable of going to the moon and Orbital's Cygnus.

A major milestone was passed recently. The ISS has been continuously occupied for 14 years. 14 years seems a long time ago and some members of the original crew look very young compared to modern astronauts.

China goes round the moon

Despite there being numerous excellent sites with details of every space mission even the supposedly top secret ones there is still the odd one that I only find out about after the event. The latest mission to fall into that category is a Chinese mini-Soyuz vehicle called Chang E5T1 that went once around the moon then returned to Earth and landed in Inner Mongolia. I have no idea why it was sent round the moon or what China learned from it as they are not exactly forthcoming.

Europa

Every time NASA submits proposals for its next set of missions there is one to Jupiter's moon Europa. Every time it gets rejected. I have no idea why that is as if I had one choice of where to send a mission Europa would be the only choice. It is a fascinating world which has a huge sub-surface ocean with twice as much water as there is in all the oceans on Earth. This time there are several influential congress members who are backing a mission to Europa.

I am convinced that eventually life will be found all over the solar system but without doubt the best chance of finding it is on Europa. It is bound to be a very interesting mission because as well as all the usual navigation and landing challenges once a vehicle lands there it has to find a way to sample the underground ocean. I wonder if they will be able incorporate a drill and a nuclear powered submarine on the mission.

The Cassini mission to Saturn's system has been fascinating especially some of the information we have learned about Saturn's moon Titan. Titan is an incredible world and it is great that we have started exploring it but Europa for me is much more interesting. If ever NASA has a binding online poll on where to send future missions expect me to be pestered to vote for Europa.

It's Bruce Willis time

Everyone who inhabits Sidepodcast knows that if a space rock is about to splatter the Earth you send Bruce Willis up to land on it then blow it to bits. Until this week landing on a space rock had never been done before so Bruce would have had no previous missions to learn from.

The European Space Agency's Rosetta vehicle took a decade to arrive at comet 67P/Churyumov-Gerasimenko. It launched on March 2nd 2004 but did not arrive at the comet until August 6th 2014. I am not sure Bruce would be happy to sit around a capsule that long. Rosetta will spend a year and a half orbiting the comet and has already sent lander called Philae to its surface. Landing on a comet is not as easy as you may think. For one thing they are very small and its gravity is 0.001% of Earth's. To overcome that Philae is fitted with harpoons and ice screws to solidly attach itself to the surface. Unsurprisingly with so little gravity the landing was a bit bouncy. Some of these devices did not activate properly but Philae was still able to send photos from the comet's surface. The lander is very small and will only transmit info for a couple of days.

For its second day on the comet's surface Philae received a batch of new orders from mission control in Darmstadt to make use of its limited power supply and its awkward landing position. Because of the way the lander is sitting its solar panels are not working as efficiently as planned and therefore the power that is there has to be used to maximum effect.

Comets are often described as cosmic snowballs. One thing we learned about this comet late on Rosetta's approach is that it is not at all spherical. It is made of two distinct lobes and viewed from the right angle it looks like a rubber duck. No-one expected that to be the case but as often happens in space exploration reality and theory have little in common.

So despite two accidents and one death there is still a lot of good news in the space business and there are still firsts being achieved. I just hope that soon we will have good news about a mission to Europa.