Smooth Moves at 17,500mph

This is a beautiful image of ATV-3 ‘Edoardo Arnaldi’ docking at the International Space Station the other day. You can see the green haze of the atmosphere, the great stars of the galaxy and the bright lights of ATV-3. I think this will be my new desktop wallpaper!

ATV-3 Docking at the ISS

ATV-3 is the third ‘Automated Transfer Vehicle‘, an unmanned supply capsule, created by the European Space Agency, used to deliver food, water, clothes and experiments to the space station. It holds a lot more than the more regular Russian Progress resupply ships. After a few months docked to the station the astronauts will fill it with rubbish and it will burn up in the atmosphere.

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War of the Worlds

ExoMars - Will it happen?

The new NASA budget isn’t looking good. $1b less than usual. That places less than 0.5% (I think actually less than 0.1%) of the federal budget in NASA. That’s despicable! What does it mean for NASA though? Well it means a lot for the branch of science I care most about, planetary science. As a result of this budget NASA have pulled all co-operation with ESA on the ExoMars project. This would see a rover and a satellite launched to Mars between 2016 and 2018. Well, maybe not anymore. What’s important about this mission is that it does so much more than what has been done before. The rover can drill 2m down into the ground, a key milestone, and the satellite would trace methane in the atmosphere. Both would help significantly in the search for life. ESA are trying to get the Russians involved instead now and the ExoMars project will probably be radically re-designed and drawn back. Shame.

Worse though, this budget demolishes a Mars Sample Return mission this decade. NASA have been told that this is their most important goal, for humans won’t be able to visit Mars until this has been done, for a variety of reasons. The next most important after that is a Europa mission (the moon of Jupiter). It is assumed that Europa has a liquid-water ocean below it’s icy surface, an ideal habitat for life. We need to find out what’s there. I haven’t seen any plans though, not even for a little orbiter.

Do NASA have their priorities in a twiddle or not? They’re investing more money in commercial spaceflight, which is good. More money in green aviation (such as blended-wing technology), which is good. More money in developing their new rocket(s), again good. But we’re not doing what we do best, explore! We need to send ambassadors, robot spacecraft, to visit the planets. There’s so much we don’t know and don’t understand. We need to find out.

Book Review: My Life on Mars

My Life on Mars: The Beagle 2 Diaries - Click image to be redirected to Amazon

My Life on Mars: The Beagle 2 Diaries by Prof Colin Pillinger.

First of all, please bear in mind that it has taken me quite a while to read this book – I’ve been rather busy over the last few months with OU studies and so on.

I was 13 on Christmas Day 2003, when Beagle 2 was due to land on Mars. I had got up extra early to pop and the news and see what had happened. It wasn’t good news.

Since then though I have always been astonished that we actually sent a mission to land on Mars, we the British people had made a lander to look for the signs of life on another world. I needed to know how it was done – finally Colin’s book came out.

It’s quite an intense book, there’s a lot of information, a lot of names to follow. I found at times that this made it slightly difficult to read, having to head back a few pages to figure out which person was being discussed now. I understand that in a project as grand as this a lot of people are involved, and at the end of the day the story needs to be told.

In this book we learn about Colin’s family history, his youth, how he became interested in science and eventually how he sent a lander to Mars. I had no idea how difficult it could be. The meetings, the letters, the phone calls, the arguments. I was very surprised about the European Space Agency, this book has changed my opinion of them, and not in a good way. Infact near the end I quite liked this quote regarding ESA ‘The way things are going the Universe will end before ESA arrives on Mars’, this referring to their Aurora programme.

If you’re interested in space exploration and want to understand how a space mission works and is put together this is a must read. It had me laughing and gasping in shock, you’ll enjoy it.

It’s 4 out of 5 from me!

Next book – The God Delusion by Prof Richard Dawkins (finally!)

Water: Where did it come from?

I haven’t done a proper science post for a while and I’m sorry for that. I saw a news story pop up on Twitter from the ESA Science Team (@esascience) about the origin of Earth’s water. Just where did it come from?

This is an area that really interests me, in fact I get rather too excited about it. We had a long and detailed question on it pop up in S283 (an OU planetary science course) and I thoroughly enjoyed researching and developing my answer. I leapt at this chance to discuss it further.

The origin of Earth's water?

The origin of Earth’s water?

It’s pretty obvious surely? Comets right? They’re mainly composed of water ice, we know the planets were pummeled by them in the late heavy bombardment about 4 billion years ago, its got to be them hasn’t it?

There has been no way to test this hypothesis until very recently. You need to send a spacecraft to a comet to test it – a very expensive but totally worthwhile test.

Now we’ve finally managed to study 4 comets in detail and the results are interesting. What we need to study is what’s called the deuterium/hydrogen isotope ratio. Deuterium is just basically a slightly heavier version of hydrogen, it has an extra neutron (technically not an extra one because hydrogen doesn’t have any neutrons).

If comets are the origin of the Earth’s water we’d expect there to be a very similar ratio of hydrogen and deuterium to the ratio of these isotopes in ocean water. From the comets that have been studied it turns out that this probably isn’t the case. Comets appear to have twice as much deuterium than ocean water, meaning that comets are an unlikely cause for our waters origins. As we’ve said already though, only a few comets have been analysed in detail. They might not be representative of all comets.

Another theory states that water-bearing grains are responsible. The distance from the Sun at which the Earth formed though casts doubt on this. It would have been so warm that water couldn’t have existed here. Not if they were incorporated within hydrated minerals though. As the planet formed (and after) these hydrated minerals would, over time, degas out into the atmosphere via volcanic eruptions. Eventually, enough was degassed  to form today’s oceans. This has been held as the most plausible explanation.

A spanner seems to have been thrown in the works though, the debate has been reignited. The Herschel infrared space observatory has been looking at comet Hartley 2 and has found that its deuterium/hydrogen ratio is pretty much exactly the same as Earth’s oceans. This comet is suspected to originally have been a trans-Neptunian object flung into the inner solar system have a gravitational tug of war. These comets, forming under different conditions to those that formed between Jupiter and Saturn, probably have slightly different compositions, specifically the deuterium/hydrogen ratio.

A recent study shows that there was likely a 5th giant planet in the solar system, but after gravitational encounters with other planets was flung out of the solar system, stirring up all the trans-Neptunian comets on its way. Is this the reason for the late heavy bombardment? It lends weight to comets being the origin of Earth’s water.

I’m still sceptical though. This is only one comet. We’re going to need to study many, many more before we reach a definitive conclusion. From what I’ve studied, hydrated minerals seem to fit best with the available evidence, but as more comes in I’m willing to change my mind.

The report from the ESA science can be read here
The report on a possible 5th giant/ice giant can be read here