JUICE is Go!

OXFORD UNIVERSITY NEWS RELEASE:

The Jupiter Icy Moons Explorer (JUICE) will explore the giant planet and its diverse collection of icy worlds, from volcanic Io, to the waterworlds Europa and Ganymede, to the ancient cratered terrain of Callisto.

Billion euro Jupiter mission approved

Joint release on behalf of Imperial College London, Oxford University, University of Leicester, and University College London; with thanks to Pete Wilton of the Oxford University Press Office.

The European Space Agency (ESA) has approved a new mission to explore Jupiter and its icy moons to reveal fresh insights into the habitability of the ‘waterworlds’ orbiting the giant planets in our solar system and beyond.

On 2 May 2012, at a meeting in Paris, ESA’s Science Program Committee voted to go ahead with the project, the Jupiter Icy Moons Explorer (JUICE), the first European-led mission to the outer solar system, and the first spacecraft destined to orbit an icy moon. The JUICE spacecraft is scheduled to launch in 2022, arriving in the Jupiter system in 2030.

Approval for the estimated billion euro contract for the mission came with UK researchers deeply involved in the leadership and planning for JUICE and playing a vital role in gaining approval for the mission ahead of rival bids. The proposal was led by a UK scientist and UK scientists make up four of the 15 members of the ESA Science Study Team for JUICE with the team including researchers from Imperial College London, Oxford University, University of Leicester, and UCL (University College London). 

The primary target of the mission is the solar system’s largest moon, Ganymede, an icy world 8% larger than the planet Mercury. Ganymede is unique within the solar system – it is thought to harbour a deep ocean under the icy crust, it has its own internally generated magnetic field, and it has an ancient surface littered with more individual types of crater than anywhere else in the solar system. 

If moons are common features of giant planets around other stars, then Ganymede may represent a whole class of potentially habitable environments in our galaxy. JUICE will carry experiments designed to study the sub-surface ocean, the geology and composition of the surface, and its interaction with its plasma environment, to assess its potential as a habitable environment in our solar system. The spacecraft will also investigate Jupiter’s other icy worlds, Callisto and Europa, as well as the giant planet’s complex atmosphere and extended magnetosphere.

Imperial, Oxford, Leicester and UCL will be among the UK institutions working to propose experiments to be carried as part of the spacecraft payload. These instruments will be specifically designed to study the gas giant, its icy moons and charged particle environment to an unprecedented level of detail, giving our most detailed characterisation of the Jovian system ever obtained.

Professor Michele Dougherty of Imperial College London, lead scientist for the JUICE proposal, said: ‘Ever since Galileo’s discovery of the four largest moons of Jupiter, we’ve wondered what it must be like on their icy surfaces, looking into a night sky dominated by the gas giant Jupiter. From the volcanic moon Io, to the potential sub-surface oceans of Europa and Ganymede and the ancient cratered terrain of Callisto, these four moons are fascinating worlds in their own right.’

As well as making close measurements of the surface, sub-surface, magnetic and plasma environment of Ganymede the mission will also focus on the other icy moons; performing multiple flybys of Callisto and two flybys of Europa. By studying all three of these icy environments the mission’s studies of Ganymede will take on a broader significance. 

Dr Leigh Fletcher of Oxford University, a member of the ESA Science Study Team for JUICE, said: ‘Scientists have had a lot of success detecting the giant planets orbiting distant stars, but the really exciting prospect may be the existence of potentially habitable ‘waterworlds’ that could be a lot like Ganymede or Europa. One of the main aims of the mission is to try to understand whether a ‘waterworld’ such as Ganymede might be the sort of environment that could harbour life.’ 

In order to assess whether Jupiter and its moons could provide habitable environments, and provide a model for gas giant systems orbiting other stars, the spacecraft will make an extensive study of the planet’s dynamic, evolving atmosphere, with its belts, zones and gigantic swirling storms, over the 3-year duration of the mission. JUICE will also study the magnetic and charged particle environment of Jupiter, which has the largest magnetosphere in the solar system, and its coupling to the moons (particularly Ganymede).

Dr Emma Bunce of the University of Leicester, deputy lead scientist for the JUICE proposal, said: ‘We need to place the possible habitability of these “waterworlds” into some broader context, and JUICE will do that by also studying the surrounding environment. Ganymede is strongly coupled to its parent Jupiter - through gravitational and electromagnetic forces – studying this interaction gives us further insight into its unique place in the solar system.’

Professor Andrew Coates of UCL, a member of the ESA Science Study Team, said: ‘Studying these watery worlds is the next vital step beyond Mars in the search for the conditions for life in our solar system. Ganymede’s unique magnetic shield helps protect it somewhat from Jupiter’s harsh radiation belts and rapidly rotating magnetosphere, and we want to understand its effectiveness. Europa and Callisto provide key comparisons as we search for the solar system’s ‘sweet spots’ for habitability.’

The data JUICE will send back about the varied environments of Jupiter and its icy moons will benefit many areas of science with geologists, astrobiologists, space and atmospheric physicists all queuing up to see how the mission’s findings will affect their disciplines.

The announcement will lead to further opportunities for British companies as they look to bid for contracts to build elements of the JUICE spacecraft and its instruments. The UK Space Agency estimates that the space industry's overall contribution to UK GDP is £7.9 billion and that it employs nearly 27,000 people, with around 60,000 more jobs enabled by the space sector.

For further information contact:

Professor Michele Dougherty of Imperial College London on mobile; +44 (0)7990 973761 or email m.dougherty@imperial.ac.uk OR Simon Levey on +44 (0)207 5946702 or email s.levey@imperial.ac.uk

Dr Leigh Fletcher of Oxford University on +44 (0)1865 272089 or email fletcher@atm.ox.ac.uk

Dr Emma Bunce of the University of Leicester on +44 (0)116 2523541 or email emma.bunce@ion.le.ac.uk

Professor Andrew Coates of University College London on mobile; +44 (0)7788 448318 or email ajc@mssl.ucl.ac.uk

Alternatively contact the University of Oxford Press Office on +44 (0)1865 283877 or email press.office@admin.ox.ac.uk

Notes to editors

*Suggested images:  More JUICE images are available here: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=50086&farchive_objecttypeid=18,19,22&farchive_objectid=30912&fareaid_2=129

*The selection of the Jupiter mission is the culmination of five years of hard work by the ESA team of scientists and engineers. ESA’s Cosmic Vision L-class competition started in March 2007 with a call to the scientific community to propose new ideas for future exploration.  A previous incarnation of JUICE was selected as one of three finalists (JUICE, Athena, and NGO), which have been going head-to-head in the ESA studies since 2010. At that time, all three proposals had significant US involvement, and the Jupiter mission was known as the Europa Jupiter System Mission (EJSM/Laplace). However, in March 2011, NASA withdrew from the L Class missions in general, and the reformulation phase began to rework the three proposals into European-led missions, leading to the evolution of the JUICE spacecraft.

*The JUICE mission relies on a strong heritage of outer solar system exploration by UK scientists, such as those involved in the Cassini-Huygens mission to Saturn and Titan.

*For more on how the space industry benefits the UK see: ‘The Size and Health of the UK Space Industry’, November 2012: http://www.bis.gov.uk/assets/ukspaceagency/docs/industry/oxecon%20executive%20summary%20for%20final%20web%20version.pdf

Destination: Ganymede

Galileo views Ganymede

Oxford Science Blog By Pete Wilton & Leigh Fletcher, to accompany the press release here.

It’s official: it was announced today that Oxford University scientists will help to prepare a mission to Jupiter and its icy moons.

But whilst the JUICE spacecraft will beam back valuable data on several of the planet’s satellites, it will give special attention to one in particular: Ganymede.

I asked Leigh Fletcher of Oxford University’s Department of Physics, one of the JUICE team, about the appeal of Ganymede, what they hope to find there, and how Oxford scientists will probe the secrets of this enigmatic ‘waterworld’…

OxSciBlog: What makes Ganymede so interesting?
Leigh Fletcher: When people think of moons in our solar system, they often imagine them as being inferior to the main planets, and somehow less interesting. The moons of Jupiter show how wrong that misguided assumption can be - the four largest Jovian moons (Io, Europa, Ganymede, and Callisto) are the size of planets, and each has a fascinating and rich geologic and chemical history. 

These moons truly are worlds in their own right, with a diverse range of unusual landscapes and features that can keep scientists busy for decades. ESA has chosen to focus on Ganymede, the largest example of an icy moon in our solar system. It is thought to be made of roughly equal measures of rocks and water ice, and is likely to harbour a saltwater ocean beneath its icy crust. For those searching for habitable environments in our solar system, the mantra has always been to follow the water, as the vital solvent for the chemical reactions of life.

Ganymede's surface has a mixture of ancient, dark, cratered surfaces, and brighter water-ice-rich regions of ridges. The biggest feature is a dark plain called Galileo Regio, visible from Earth even through amateur telescopes, and may even have polar caps of water frost.  Furthermore, Ganymede has an extremely tenuous oxygen atmosphere, and is the only moon in our solar system with a magnetic field, probably caused by convection within a liquid iron core.

OSB: How does it compare to Jupiter’s other moons?
LF: To better understand Ganymede, it's important to consider the processes which shaped its evolution and surface features by comparing it to the other Galilean moons: although these four worlds of fire and ice probably had the same origins in the Jovian sub-nebula, their present-day structure is the end of product of aeons of subsequent evolution. Jupiter's immense gravity causes tidal flexing of the moons (strongest at Io, weak or absent at Callisto), providing energy to liquefy the water ice crusts and produce internal activity.

Io is mostly rocky, lacking the water ice of the other satellites but featuring hundreds of active volcanoes. Europa is the smallest of the four, with a smooth geologically-young icy surface overlying a water ocean, heated by the tidal flexing from Jupiter. Ganymede's ocean is likely to be deeper than Europa's, under a thicker ice crust. Callisto is further away and experiences less tidal heating, resulting in an ancient terrain, one of the most highly cratered surfaces in the solar system.

OSB: What do we hope JUICE will find out about it?
LF: JUICE will be the first orbiter of an icy moon, and provide a full global characterisation of its surface composition, geology and structure. An ice-penetrating radar will peer through the icy crust for the first time, providing us with our first access to the water ocean of a Galilean moon. Our key goal is to assess the potential habitability of Ganymede as a representative of a whole class of ‘waterworlds’ which may exist around other stars, building upon the discoveries of habitable environments on the Earth's deep ocean ridges.  So JUICE will be looking for key characteristics of habitability on Ganymede - sources of energy, access to crucial chemical elements, liquid water, and stable conditions over long periods of time.

It's a crucial step in our reconnaissance and exploration of our solar system, and towards answering the question of 'What are the necessary conditions that make a planetary body habitable?’ By comparing the three potentially ocean-bearing Galilean moons, we hope to identify the physical and chemical characteristics driving the evolution of this planetary system.

JUICE will study the extent of Ganymede's ocean, its connection to the deep interior and ice shell; the global distribution and evolution of surface materials, geologic features, and present-day surface activity; and the interaction with the local environment and magnetosphere. In addition, JUICE will explore recent activity and composition on Europa, and characterise Callisto as a remnant of the early Jovian system. Finally, JUICE will be capable of exploring the wider Jovian system, from the complex and dynamic Jovian atmosphere, the magnetosphere, the minor satellites and rings.

OSB: What instruments will be needed to study it?
LF: The proposed JUICE payload has cameras to take images of the icy moon surfaces and swirling Jovian clouds; spectrometers covering ultraviolet, near-infrared and sub-millimetre wavelengths to determine moon compositions and temperatures, winds, composition and cloud characteristics on Jupiter; a magnetometer and plasma instruments to conduct an investigation of Jupiter's magnetosphere; and a laser altimeter, ice-penetrating radar and radio science instrument to probe below the surface of the Galilean moons and through the Jovian cloud decks. 

The payload is just a model right now, and other instruments could be added. All this will be launched on a 5 tonne spacecraft in 2022, with solar arrays to provide power and a large high-gain antenna to return the data to Earth. It will take 7.5 years to reach the giant planet, before going into orbit around Jupiter to conduct an extensive survey of the whole planetary system. Then, in the final phase in 2032, it will enter orbit around Ganymede.

OSB: How are Oxford scientists likely to contribute?
LF: Oxford has a strong heritage of contributing instrumentation and data analysis techniques for outer solar system missions, notably with the near infrared mapping spectrometer (NIMS) on Galileo and the composite infrared spectrometer (CIRS) on Cassini.  We also have a long-term campaign of giant planet studies from ground-based observatories in Hawaii and Chile and space-borne telescopes (Spitzer, Herschel, Hubble). This has allowed us to contribute to the science case for a return mission to Jupiter and its icy moons, identifying the key questions and mysteries left unanswered by previous generations of spacecraft.

Oxford, along with many other UK institutions, will hope to contribute instrumentation to fly to Jupiter to address some of these questions. Involvement with Galileo and Cassini enabled Oxford to build up a rich planetary science group, with a broad range of experience from lab spectroscopy to spacecraft hardware, and from icy moons to gas giant dynamics. This expertise will help us to solve the challenges presented by the JUICE mission.

OSB: What is the next big milestone for the JUICE mission?
LF: Now that the mission has been officially selected by ESA as the L-class mission for 2022, the hard work really begins. Industry will be invited to design and build the spacecraft systems, and an announcement of opportunity will be issued to call for instrument designs. Teams will be assembled to thrash out ideas for instruments that address key scientific questions, all hoping to see their particular design on the launch pad when we lift off for Jupiter in a decade's time.  The final go-ahead for the mission from ESA, known as 'adoption', should come in the next 2-3 years.

Pythagora's Trousers

At the end of April, Chris North (University of Cardiff, BBC Sky at Night, @chrisenorth) interviewed me for the Pythagoras’ Trousers radio podcast, which was broadcast on Monday April 30th on Radio Cardiff.  We spent 20 minutes discussing the outer solar system, with themes ranging from the formation of the giant planets and why the gas and ice giants appear so different; future missions to explore the giant planets and their icy moons; and professional-amateur collaborations on giant planet storm tracking.  We focussed for a while on future Jupiter missions, including Juno (en route and due to arrive in 2016) and JUICE (the ESA Jupiter Icy Moons Explorer, due to arrive in 2030).

The podcast can be downloaded from the following website.  Here’s their write-up:

Small businesses in Wales and astronomy
On this week’s programme, Rhys talks to Peter King from DPI Limited about job opportunities for science and engineering graduates amongst small businesses in Wales and our STEM Ambassador of the Week is Brij Geerjanan from Tata Steel. Later on, Chris North talks to Leigh Fletcher from the University of Oxford about the outer solar system and Hugh Lang guides us through the night sky throughout May. Finally, this week’s Subject of Science looks at the history of the zip.

http://www.rhysphillips.co.uk/pythagoras-trousers/episode-78/

Pythagoras’ Trousers is a radio show from the South Wales Networks of theInstitution of Engineering & Technology and Radio Cardiff. Each week, presenter Rhys Phillips takes a look at stories of interest from the worlds of science, technology, engineering and mathematics, bringing these fields to a wider audience and promoting these subject areas to school pupils.
The show is broadcast on Radio Cardiff every Monday evening 8-8:30pm and repeated Tuesday nights 11-11:30pm.

University College Movies

Back in February I was visited by a film crew working for University College Oxford to showcase some of the work we do in Atmospheric Physics here in Oxford.  You can see the finished product on vimeo.com.  Hats off to Kerry Harrison of kerryharrisonphotography.com for some great footage!



Dr Leigh Fletcher from University College Oxford on Vimeo.

At Univ... from University College Oxford on Vimeo.

School Explorers

Recently I received a package of 30 or so letters from primary school students in Hinckley, Leicestershire (my old home town), and so I set about replying to them.  The letter I sent in reply is recorded below, as I think it’s a great insight into how powerful space exploration can be in inspiring the next generation of explorers.  I hope it’s helpful to others too!

“Thank you very much for all the letters you sent to me here in Oxford, it's so nice to know that people out there are interested in the work that we do, using our telescopes to look up at the night sky, trying to understand what it must be like on the other planets in our solar system.  What would it be like to stand on the red dusty landscape of Mars under pink skies with blue sunsets?  What would you hear if you stood in the middle of a gigantic lightning storm on Jupiter?  Are there other worlds out there with life forms, walking around, sitting in schools, and asking questions about the night sky, just like you?  I love my job as a space scientist, dealing with these sorts of questions every day.   So I'll do my very best to answer all the questions you sent!

Questions about my job:

Lots of you wanted to know what NASA stands for - it's the National Aeronautics and Space Administration, an American government institution that manages the US space program.  There's lots of NASA centres throughout the United States, and I work closely with two of them - Goddard Spaceflight Center near Washington DC, and the Jet Propulsion Laboratory in California.  Lily, Anjan, William, Alisha and Joe wanted to know where I was based in America - we lived in California, and I worked for the Jet Propulsion Laboratory.  Sakithya and Eden wanted to know how many people work at NASA  - the answer is thousands, it’s a huge effort to send things into space.  Here in Britain we have a much smaller agency called the UK Space Agency (UKSA), and with the rest of Europe we're all part of the European Space Agency (ESA).   

Many of you asked what it's like to be a space scientist.  I work in an office with lots of other scientists, using computers to understand what it's like on other planets.  We build spacecraft to launch to other worlds and fly around them, sometimes to land on them to explore like a mini car on the surface.  We also build big telescopes to fly in space and look out at the planets (you may have heard of Hubble), and we get to use big telescopes on Earth (some of them in Hawaii and Chile).  It's a very exciting time, as telescopes and spacecraft get better and better, and we're learning more every day. One of the things we're looking for is a sign of life elsewhere in our solar system, but more on that later. Eden and Spencer wanted to know about the computers we use: I have about 3 different computers for different things, but we wouldn't be able to do our job without them - it's essential to be good at maths, and good at computing, to be a space scientist.

Joe, Daisy and William wanted to know how I got this job.  When I left school in Hinckley at 18 years old, I went to university to study science, specifically physics.  Once I was trained, I became a Doctor at the age of 26 (not of medicine, but a doctor of science), and started figuring out new ways of studying the planets.  I spent a few years living in America, working for NASA, and that landed me the job I have today, as a researcher at Oxford University.  K. Galloway wanted to know if the students at Oxford are well-behaved: I can tell you that they are most of the time, but every now and then they'll get into trouble!  Keerthan wanted to know how long I've been a space scientist - the answer is about 8 years now.  

About Astronauts:

Ruby, Holly, Lily and M. Brookes wanted to know if I ever get to go into space.  Sadly not, because I'm not trained as an astronaut.  I tried once, when the European Space Agency wanted astronauts to work on the International Space Station, but it's very hard to get a job like that.  So I do the next best thing, sending big robotic spacecraft into space.  Daisy wanted to know how you get to be an astronaut - you have to be physically fit, with good eyesight and excellent problem solving skills.  They want you to be able to think quickly and make good decisions.  Typically people are between the age of 18 and 28 when they apply, and it takes years to train before you get your first mission to fly into space.

Callum wanted to know if NASA sends astronauts into space - they certainly do, but now that the American space shuttle has stopped working, they have to fly on Russian rockets.  Anjan and Francesca wanted to know how many space shuttles there were - there are three still in existence (Discovery, Endeavour and Atlantis), but two blew up during missions (Columbus and Challenger), showing you just how dangerous space travel is today.  To answer Beth's and Francesca's question about how many people have flown in space, about 530 people have flown up there so far (an altitude of 62 miles up).  Francesca wanted to know what's the longest time anyone has spent in space - 438 days, a record set by a Russian named Polyakov on the Mir space station in 1994.  Lily and Aryana wanted to know when the first astronauts went into space - it all started in 1961 with Yuri Gagarin, a Russian who was the first man in space, over 50 years ago.  Jude and Beth asked questions about the first man on the moon, Neil Armstrong:  he was selected as a NASA astronaut when he was 32, flew on a Gemini mission when he was 36, and landed on the moon when he was 39.  The total time he spent in space was 8.6 days.

Keerthan and Spencer asked how long it takes to get to space - the space shuttle used to take about 8 minutes from launch in Florida to get into orbit.  Daisy, Ethan and Eden asked how long it takes to build the spaceship in the first place, and it's several years - the space probes I work on take at least 10 years to design, build and get to the launch pad, and they're about the size of an average car.  Eden wanted to know how much fuel it takes - well the space shuttle used about 2 million litres to launch into space, that's the same as about 50'000 cars!  Alisha wanted to know what you eat in space and why - well it's pretty much the same as on Earth, except they tend to dry it out so it doesn't weigh as much, then add water back to it later.  One day you must really try some freeze-dried strawberries!

About space:

Now we get to some of the more scientific questions.  Joe wanted to know when the universe began - well we don't know for certain, but we think that it was nearly 14 billion years ago, which is 14'000'000'000 years.  The Earth has only been around for about 4.5 billion years, for comparison.  M. Brookes wanted to know how big is space -  well that’s a hard one, as we think the universe is infinitely large, so if you set off in one direction, you'll carry on going forever and ever and never reach the end of it!  

Spencer asked how cold it is in space, and that's a good question - on Earth the air around us keeps us warm (it's an insulator), but as there's no air in space, there's no way to stay warm.  The temperature goes right down as low as it can go, about -270 degrees celcius (270 degrees below).  Eden asked why space is dark - it's because space is so empty and cold, there's nothing out there producing light except for the stars.  On a similar note, Kayleigh, Ethan and Spencer asked why the sun is so hot - the Sun is a big glowing ball of super-heated gas, so hot you can feel it's warmth from millions of miles away, and it's powered by something called nuclear energy, a little like the energy they produce in nuclear power stations here on Earth.  Jacob and Aryana wanted to know how big these stars are - the biggest are 2000 times bigger than our own Sun, but the smallest are about the same size as our planet Earth.  Our own star, the Sun, is 100 times wider than planet Earth!

About Planets:

OK, now we're onto my favourite topic, the planets in the solar system.  Lots of you wanted to know how big the solar system is - well, it's 3.7 billion miles to Pluto, which would take you 7000 years to drive in the car, but even that's not the edge of the solar system, as the effects of the Sun can be felt 25 times further out than Pluto. So the solar system is big, and there’s a lot to explore.  Aryana wanted to know how old the solar system is, and we think it's about 4.5 billion years old.  Some of the rocks on Earth (in Scotland, actually) are thought to be almost this old.

Ruby, Jude, Daisy, C. Sutton, Francesca and K. Galloway all wanted to know a bit more about Pluto.  We used to call Pluto a planet (the ninth in the solar system), but over the past few years scientists have begun to realise that there are many more objects like Pluto out there in the distant solar system.  We had a choice, we either call them planets (so you'd have to learn hundreds of names, rather than just the eight of Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune), or we call them dwarf planets, of which Pluto is the largest.  We chose to call them dwarf planets, but that doesn't stop them from being very interesting places!

Anjan, Joe and Francesca asked about moons in the solar system, and just like dwarf planets, these can be really interesting places.  Not all planets have moons, and most of the best ones orbit around the giant planets, Jupiter (63 moons), Saturn (62 moons), Uranus (27 moons) and Neptune (13 moons).  My favourites are Europa (a moon of Jupiter with an icy ocean) and Titan (a moon of Saturn with a thick, smoggy orange atmosphere).  Francesca wanted to know how many craters there are on our moon, but there are really too many to count, at least 300'000 we can see through our telescopes. On the same note, Freya, Kayleigh, William, Daisy and Aryana wanted to know how Saturn got its rings, and that's a really good question.  We don't really know, but we suspect that an old moon got torn apart by some big collision, and the debris formed the beautiful rings.

Lots of you asked about the sizes of the planets, so here's a good way to think about it.  If the Earth and Venus is about the size of a grape, then the Sun is about the size of a person, Jupiter is about the size of a grapefruit, Saturn an orange, and Uranus and Neptune the size of lemons.  Joe asked why Jupiter is so big - it's because it sucked in lots of hydrogen and helium gas and got all puffed up when it first formed.  

Eden asked why Mars is red - it's because the dust on Mars contains the same material as rust here on Earth, and it coats all the rocks to give the red colour.  William asked about the comet Hyakutake, a comet that came near Earth in 1996 but won't return for thousands of years - it's about 2.6 miles across, but gives off a tail that extends for hundreds of thousands of miles across the solar system.  William asked about the weight of the asteroid belt, the band of rocks that exists between Jupiter and Mars, and we think it weighs about 1/20th of the mass of our moon.  Freya asked about Jupiter's great red spot, a giant swirling hurricane that's been raging for centuries, but I'm afraid no one really knows why it's red, as we don't know what the chemical is that's responsible for the red colour!  But we do know the answer to her other question about Venus' poisonous clouds, as we know Venus' hot atmosphere contains lots of sulphuric acid droplets, which rain down like acid rain onto the surface.  Not a nice place to go on your holidays!

Life:

The last section is about life.  We said at the very beginning that the job of a space scientist boils down to two very simple questions - is there life somewhere else out there, and what made conditions just right here on Earth for you and me to be asking these questions?  Joe asked how has Earth got life on it, and we think that the conditions were just right for us to get energy from the Sun (causes plants to grow for us to feed on) without being too hot (like Venus) or cold (like Mars) for life to get started.  Kayleigh asked whether there is any life on Mars - all the Mars rovers and probes we've sent have suggested that Mars used to be a bit wetter, like the Earth, which might have been right for life to exist, but we've never found any evidence of even the simplest life forms, like tiny bacteria or viruses, so we think it's a dead world.  Sakithya and Holly also asked whether there was life on the moon, and I'm afraid that the answer is definitely not - there's no liquid water or any atmosphere that would allow life to exist, so it's dead and cold up there.

Spencer asked if we've ever found any intelligent life forms?  Not yet, but we're going to keep trying.  In the last ten years we've discovered hundreds of planets around other stars, some of them are Earth-like, but still not quite right for life to exist. We're listening with giant telescopes, just in case there is any intelligent life out there sending signals to us, but no signs yet.  But one thing's for sure - there are millions of planets out there, and if there's only life here on Earth, then the universe is a very lonely place.....

I hope that's answered some of your questions, and that it's encouraged you to keep on exploring!

Best wishes,

Dr. Leigh Fletcher,

Oxford University

April 2012"

Long Distance Storm Chasing - A Plea for Help!

Last spring, Saturn’s gigantic springtime disturbance was characterised for the first time in the infrared, allowing us to measure the vertical temperature structure of a Saturnian storm system.  Our paper (Fletcher et al., 2011, Thermal Structure and Dynamics of Saturn’s Northern Springtime Disturbance, Science, 332, 1413--1417, http://dx.doi.org/10.1126/science.1204774), showed that the thermal infrared imaging yielded some surprises - not least was the dramatic effect that this churning, tropospheric storm system had on the usually calm and quiescent stratosphere (see Saturn image on the far right).  It spawned two warm airmasses, which we termed ‘beacons’ because of their impressive emission at infrared wavelengths.  These heated airmasses were tracked throughout 2011 by Cassini, the Very Large Telescope in Chile, and the Infrared Telescope Facility in Hawai’i.

Today (February 2012), a single large hot airmass remains in Saturn’s stratosphere, but there’s a big question remaining - does this have any impact on the visible cloud tops?  Indeed, one of the big challenges for giant planet science is relating visible changes in albedo and cloud colouration to environmental changes (e.g., changes in temperature, cloud formation or chemistry).  So far, our comparisons with visible light observations have suggested that the effects of the hot stratospheric beacon are completely invisible.  The chart above shows the expected longitude (System III West) of the beacon, and an Excel spreadsheet listing the longitude on each date through the rest of 2012 can be found here:
http://www.atm.ox.ac.uk/user/fletcher/io/saturn/beacon_location_27feb2012.xls  

As Saturn reaches opposition on April 16th 2012, the next few months provides an excellent opportunity to search for any unusual goings-on beneath the hot beacon.  To find the System III Longitude visible from Earth at any time, use the JPL Horizons Ephemeris Generator (with option 14 for the table settings).

Wishing you clear skies and happy storm chasing!

Cheers,
Leigh

Becoming a Planetary Scientist

In 2012, I was asked a series of questions about how I became a planetary scientist, and what advice I’d give to school students wanting to get involved in this exciting field.  I’ve reproduced my answers here, just in case it serves to help any visitors to this site!

Job Title: Planetary Scientist

What do you actually do? 
I’m a planetary weather man, studying the physics and chemistry of all the atmospheres in our solar system to better understand the worlds around us.

What did you choose to do once you could leave school, ie at age 16?
Stay on at sixth form college to study A Levels – Maths, Further Maths, Physics, Chemistry, Biology and General Studies

What did you choose to do next?
Went to University:  Emmanuel College Cambridge to study for a BA and MSci in Natural Science, specialising in Physics.

How did you get to where you are now?  
When I left University, I really wanted to study a topic that I felt was close to home, that some day we could reach out and touch with our own hands, see with our own eyes.   Despite an interest in astronomy, I decided against studying the far reaches of our universe and chose instead to explore the planets of our own solar system.  In 2004, the Cassini-Huygens spacecraft was about to arrive at Saturn, and Oxford were looking for research students to help analyse the first data from the ringed world.  I spent my PhD characterising Saturn’s dynamic atmosphere, which then set me on a course to study all of the giant planets in our solar system in a series of short fellowships at NASA’s Jet Propulsion Laboratory and Oxford’s Planetary Physics department.  Today I use a variety of interplanetary spacecraft, orbital telescopes and giant ground-based observatories to learn more about the planets.

Were there other routes you could have taken to get this job?
Planetary science requires you to be a jack of all trades:  being a planetary scientist requires an excellent knowledge of physics, computing, maths and chemistry, so each of these topics would have allowed me to work in this exciting field, provided they’d been studied to degree level.

What do you like best about your job?  
Things can change quickly, and we have to be responsive to that.  If an asteroid strikes Jupiter, or a storm explodes in the atmosphere of Saturn, we have to bring all our experience to try to understand what’s happening.   So the days are never dull, and you rarely do the same thing from one day to the next!  I get to work as part of an international team of scientists, which means I get to travel far and wide to communicate my research and forge new collaborations.  Finally, we find ourselves in a revolution in this subject, with more missions and telescopes in flight than at any point in humankinds history – that means that the potential for new discoveries is enormous, and you never know when you might be the first human to observe a new phenomenon in our solar system.  The old adage is true – when you love what you do, you never work a day in your life!

What would your top tips be to a 16-year old considering working in this field?  
For any scientific subject, it’s essential to get a good grounding in maths and computing, as these topics go hand in hand.  So much of what we do requires the ability to write computer code and solve mathematical problems, that you really can’t escape it!  Without a doubt, you should forge ahead with A-levels, but never forget the bigger picture – there’s so much exciting science happening out there; if you read widely you might just stumble across a topic that really excites you.  That’s what happened to me with planetary exploration.

What would your top tips be to an 18 year old considering working in this field?
Think carefully about where you’d like to go for your degree, and make sure that the institution provides a good balance between science, maths and computing.  All three are needed to be a successful atmospheric scientist or meteorologist.  It’s all about building up a toolkit of experience, which you can then apply to new problems as they’re presented to you.  So be curious, don’t be satisfied with explanations that are unclear, and experiment for yourself.  Curiosity and the ability to solve problems are the traits that are essential in any independent research scientist, and will be vital as you head to university.

Tell us something about yourself.  
In the summer of 2009, I was having a barbeque on a sunny California day with my wife.  My boss called to say that an Australian amateur astronomer had spotted something rather odd near Jupiter’s south pole.  I raced to the office, where we could remotely use the telescopes in Hawaii to figure out what was going on, and we were in for a massive surprise.  A huge, super-heated plume of aerosols and debris had been lofted into Jupiter’s atmosphere by an asteroidal collision.  Without the data we took that Californian evening, we might never have been able to unravel the mystery of what had happened up there on Jupiter.  It was the chance of a lifetime, a stroke of luck, and provided us with fascinating scientific results for years to come.  It shows just how exciting this field is, and that there are so many surprises and marvels out there for us to explore.