Archive for NASA

Honoris Causa, Dr Chryssa Kouveliotou

Posted in Education, The Universe and Stuff with tags , , , , , on July 10, 2014 by telescoper

This morning I had the privilege of participating in a graduation ceremony at the University of Sussex. It was great to get to shake the hands of all the successful graduates as they crossed the stage to receive their degrees. I hope I’ll be able to collect a few pictures of the occasion and post them in due course.

 

Kouveliotou

I also had the privilege of being able to present an extremely distinguished honorary graduand, Dr Chryssa Kouveliotou. Here the oration I delivered, which I’m posting simply to record her amazing achievements and to underline that she is one of many people who have done the MSc in Astronomy at Sussex University and gone on to do great things…

 

Vice-Chancellor,

It is both a pleasure and an honour to present for the award of the degree of Doctor of Science, Dr Chryssa Kouveliotou.

Inspired by watching Neil Armstrong take his first step on the moon, Dr Kouveliotou always wanted to be an astronaut but, with no such opportunities apparently on offer in her native, she instead chose a career in astronomy. However, when she completed college Greece her astronomy professor (who shall remain nameless) advised her that there was no future for her in astrophysics. She has never known whether he really thought it was a poor choice or whether it was because she was a woman. Determined to follow her own path, she disregarded him completely and, even though her open-minded parents’ preference was for her to settle down and stay in her home country, she left to study for her Master’s degree in Astronomy at the University of Sussex; the topic of her dissertation was “The Sodium emission cloud around Io: mapping and correlation with Jupiter’s magnetic field”. She received the MSc in Astronomy in 1977. Although the topic of her subsequent research was rather different, the connection with magnetic fields remained strong.

Dr Kouveliotou then moved to Germany to do postgraduate research on the-then very new topic of gamma-ray bursts. Indeed, she may well have been the very first person to complete a thesis on this, which remains to this day an extremely active and exciting field of research. Gamma-ray bursts are considered to be the most powerful explosions in the universe, second only to the Big Bang itself.

After completing her PhD, Dr Kouveliotou returned to Greece to teach Physics and Astronomy at the University of Athens. All the while she knew that she really wanted to do research so spent her free time pursuing this goal. Every vacation and on her one-year sabbatical she went to the USA to undertake research at the National Aeronautics and Space Administration (NASA). Her work was on solar flares but she moonlighted during evenings, nights and weekends researching her ‘first love’ gamma-ray bursts. Because of the research she undertook outside her “day job”, she found a series of bursts which all came from the same part of the sky and, as a result, became part of the discovery team for a brand new phenomenon called a soft gamma-ray repeater.

By observing gamma rays produced in space, her team discovered an example of a new class of exotic astronomical object called a magnetar, an object which has a magnetic field trillions of times stronger than that of the Earth. A magnetar is now known to be a type of neutron star, a burnt-out relic resulting from the death of an ordinary star in a supernova explosion.

Dr Kouveliotou has always loved to ask big questions, to look at the universe and ask how nature expresses itself. By overcoming obstacles in her path she really has reached the stars. In January 2013 Dr Chryssa Kouveliotou was named the Senior Scientist for High Energy Astrophysics, Science and Research Office at NASA’s Marshall Space Flight Center in Hunstville, Alabama.

She has received many awards for her work, including the Dannie Heineman Prize for Astrophysics and the NASA Exceptional Service Medal in 2012 and the NASA Space Act Award in 2005. She was also named amongst Time Magazine’s 25 Most Influential People in Space in 2012. In 2003 she was honoured with the annual Rossi Prize by the High Energy Astrophysics division of the American Astronomical Society for a significant contribution to high-energy astrophysics. In 2002 she received the Descartes Prize which recognises scientific breakthroughs from European collaborative research in any scientific field. In the awards bestowed upon her she has also been recognised for her effectiveness at creating the sort of large collaboration needed to make effective use of multi-wavelength astronomical observations.

Dr Kouveliotou has published almost 400 papers in refereed scientific journals and has been amongst the top 10 most-cited space science researchers in the academic literature across the world. She has been elected chair of the Division of Astrophysics of the American Physical Society and is a member of the Council of the American Astronomical Society, of which she chairs the High Energy Astrophysics Division.

Vice-Chancellor, I present to you for the degree of Doctor of Science, honoris causa, Dr Chryssa Kouveliotou.

 

 

Article of the Day!

Posted in The Universe and Stuff with tags , , , , , , on July 31, 2013 by telescoper

Back in the office today, the heatwave having given way to grey drizzle and cool breezes (at least for the time being). I’ve got stacks of paperwork to catch up on, but fortunately I’ve got time to post a quick congratulatory message to Ian Harrison, who is author of today’s NASA ADS Article of the Day! Ian is a PhD student in the School of Physics & Astronomy at Cardiff University and was supervised by me until I abandoned ship to come here to Sussex earlier this year; he’s got a postdoctoral research position lined up in the Midlands (Manchester) when he finishes his thesis. The other author, Shaun Hotchkiss, is coming to Sussex as a postdoctoral researcher in October.

Anyway, the paper is a nice one, called A consistent approach to falsifying ΛCDM with rare galaxy clusters. Here’s the abstract:

We consider methods with which to answer the question “is any observed galaxy cluster too unusual for ΛCDM?” After emphasising that many previous attempts to answer this question will overestimate the confidence level at which ΛCDM can be ruled out, we outline a consistent approach to these rare clusters, which allows the question to be answered. We define three statistical measures, each of which are sensitive to changes in cluster populations arising from different modifications to the cosmological model. We also use these properties to define the “equivalent mass at redshift zero” for a cluster — the mass of an equally unusual cluster today. This quantity is independent of the observational survey in which the cluster was found, which makes it an ideal proxy for ranking the relative unusualness of clusters detected by different surveys. These methods are then used on a comprehensive sample of observed galaxy clusters and we confirm that all are less than 2σ deviations from the ΛCDM expectation. Whereas we have only applied our method to galaxy clusters, it is applicable to any isolated, collapsed, halo. As motivation for future surveys, we also calculate where in the mass redshift plane the rarest halo is most likely to be found, giving information as to which objects might be the most fruitful in the search for new physics.

In case you’re wondering, the rather Popperian nature of the title is not the reason why I’m not among the authors. I’m just not the sort of supervisor who feels he should always be an author of papers done by his research students even when they had the idea and did all the work themselves. From what I’ve heard talking to others, we’re a dying breed!

Cosmic Swirly Straws Feed Galaxy

Posted in The Universe and Stuff with tags , , , , , on June 5, 2013 by telescoper

I came across this video on youtube and was intrigued because the title seemed like a crossword clue (to which I couldn’t figure out the answer). It turns out that it goes with a piece in the Guardian which describes a computer simulation showing the formation of a galaxy during the first 2bn years of the Universe’s evolution. Those of us interested in cosmic structures on a larger scale than galaxies usually show such simulations in co-moving coordinates (i.e. in a box that expands at the same rate as the Universe), but this one is in physical coordinates showing the actual size of the objects therein; the galaxy is seen first to condense out of the expanding distribution of matter, but then grows by accreting matter in a complicated and rather beautiful way.

This calculation includes gravitational and hydrodynamical effects, allowing it to trace the separate behaviour of dark matter and gas (predominantly hydrogen).  You can see that this particular object forms very early on; the current age of the Universe is estimated to be about 13 – 14 billion years. When we look far into space using very big telescopes we see objects from which light has taken billion of years to reach us. We can therefore actually see galaxies as they were forming and can therefore test observationally whether they form as theory (and simulation) suggest.

Sic Transit Gloria Monday

Posted in The Universe and Stuff with tags , , , on June 11, 2012 by telescoper

I can never resist a terrible pun, so thought this would be an especially  good day to post this video from NASA’s Solar Dynamics Observatory,  showing views of last week’s Transit of Venus taken at several different wavelengths..

 

Tinker Tailor Soldier…Astronomer?

Posted in Science Politics, The Universe and Stuff with tags , on June 4, 2012 by telescoper

telescoper:

Tinker Tailor Soldier…Astronomer?

Originally posted on The e-Astronomer:

Not often I write two posts in one day, but here is an unexpected piece of news. It seems that the US National Reconnaisance Office have given two free telescopes to NASA. Its all explained at this NY Times article. They are as big as HST but have a wider field of view. They were designed for looking down of course.  Apparently there has been a secret study team and their conclusion is that one of these beasts would be perfect WFIRST, which had seemed to be kicked into the long grass.

They don’t exactly have the rest of the money yet or an actual approval … but the WFIRST fans are talking about shooting for 2020 … a year behind Euclid.

Ooooo what fun. Spot of healthy competition.

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JWST: Over and Out?

Posted in Science Politics, The Universe and Stuff with tags , , , , on August 23, 2011 by telescoper

News filtered through recently that the cost of the James Webb Space Telescope, which is already  threatened with cancellation owing to cuts in NASA’s budget, is now estimated to be around $8.7 billion dollars, about $2.2 billion higher than previous figures. In fact about a decade ago, when I was a lad, and chair of the old PPARC Astronomy Advisory Panel, the price tag of  the NGST (Next Generation Space Telescope), as it was then called, was put at significantly less than one billion dollars.

The implications of cancelling JWST are profound on both sides of the Atlantic. As Mark McCaughrean explains in detail over on the e-astronomer, the European Space Agency has already made a substantial investment in JWST and planned future contributions include the launch and substantial operating costs. The instrument development is nearly finished, but whether there will actually be a telescope to put instruments on remains to be seen. It’s clear that this, together with previous unilateral decisions by NASA, is putting some strain on the relationship with ESA.

There were many who reacted to the initial suggestion that JWST should be cancelled by arguing that it was mere political posturing by Republicans in the House of Representatives and that it could and would be reversed if appropriate campaigning took place. To this end there has been, e.g.,  a letter to the White House Science Advisor (here for non-US astronomers and there for US ones). There’s also been a letter of support from the President of the Royal Astronomical Society. NASA’s administrators have also apparently come up with a plan to divert funds from other projects to support it. These efforts notwithstanding I get the distinct feeling that cancellation of JWST is a very real prospect and it goes without saying that the chances of avoiding it are not helped by  the increased estimated expense.

I’ve talked about this to a number of astronomers and cosmologists over the summer and found very mixed views not only about  (a) whether JWST will be cancelled or not but also about (b) whether it should be cancelled or not. Even astronomers have expressed exasperation with the spiralling cost of JWST and pointed out that if we had known a decade ago that it would take so long and involve such an outlay then it would never have gone ahead in the first place.

So let me try a straw poll:

Not Now, Voyager

Posted in The Universe and Stuff with tags , , , , , , on July 10, 2011 by telescoper

Last week I found myself a bit perplexed by the frenzy of twitter angst surrounding the last ever launch of the Space Shuttle. It’s not the first time something like this has happened. I’ve often felt like there must be something wrong with me for not getting agitated over such things. After Altantis returns to Earth in a couple of weeks’ time she will be taken out of service and, for the foreseeable future, America will no longer have the ability to put humans into orbit. This does mark the end of an era, of course, but is it really something to get all upset about?

I find myself agreeing with the Guardian editorial, which I’ve taken the liberty of copying here:

Fewer than 600 people have been admitted an exclusive club: space travel. Now, with the last flight of the space shuttle under way, the membership list is harder to join than ever. When Yuri Gagarin orbited the earth, half a century ago, and when astronauts landed on the moon eight years later, it would have been inconceivable to think of a time when manned space flight began to slip from the present to the past. But America, at least for the moment, no longer has the capacity to send people into space. In terms of national pride, this may be a failure. In terms of scientific advancement, it may not matter that much at all. Deep space exploration – using robot probes – is a very different and more useful thing than the expensive and unreliable effort to send human beings into low earth orbit, no further from Cape Canaveral than New York. The shuttle has been an icon of its age, but its human passengers – however brave and skilled – have made their flights as much to show the world what America could do as for any particular and necessary purpose. Even the International Space Station, extraordinary though it is, could operate without a human presence, its experiments automated. The only good argument for sending people into space is the simple daring of it – the need, as Star Trek used to claim, “to boldly go where no man has gone before”. Visit Mars, by all means – but there is little to be gained by sending astronauts to orbit this planet, not all that far above our heads.

For me, the most remarkable thing about the Space Shuttle is how matter-of-fact it has become. It’s rather like Concorde, which was an engineering marvel that people would drop everything and gawp at when it  first appeared, but which soon became a part of everyday life. Technology is inevitably like that – what seemed remarkable twenty years ago is now pretty commonplace.

I had similar feelings a couple of  years ago, when Planck and Herschel were launched. Of course I was extremely nervous then , because many of my colleagues had invested so much time and effort in these missions. However, watching the behaviour of the mission control staff at ESA during the launch it struck me how routine it all was for them. It’s a great achievement, I think, to take something so complex and turn it into an everyday operation.

Incidentally, it always strikes me as curious that people use the phrase “rocket science” to define something incredibly difficult. In fact rocket science is extremely simple: the energy source is one of the simplest chemical reactions possible, and the path of the rocket is a straightforward consequence of Newton’s laws of motion. It’s turning this simple science into working technology where the difficulties lie, and it’s a powerful testament to the brilliance of the engineers working in the space programme that workable solutions have been found and implemented in working systems.

So now the era of the Shuttle has passed, what next? Should America (and Europe, for that matter) be aiming to send people to Mars? Should manned spaceflight resume at all?

Different people will answer these questions in different ways. Speaking purely from a scientific point of view I would say that manned space exploration just isn’t cost effective. But going to Mars isn’t really about science; going to the Moon wasn’t either. It’s partly an issue of national pride – note how loss of the Shuttle programme has effectively ended America’s dominance in space, and how keenly that has been felt by many US commentators.

Others argue that manned space flight inspires people to become scientists, and should be done for that reason. I can’t speak for anyone but myself, and I’m sure there will be many who disagree with me, but it wasn’t the Apollo missions that inspired me to become a scientist. When I was a kid I found the footage of people jumping around on the Moon rather boring, to be honest. What inspired me was the excellent science education I received at School. And just think how many physics teachers you could train for the cost of, e.g. the ESA Aurora program

Another argument is “because it’s there” or, as Walt Whitman put it,

THE untold want, by life and land ne’er granted,
Now, Voyager, sail thou forth, to seek and find.

As a species we have an urge to set challenges for ourselves, whether by asking difficult questions, by designing and building difficult devices, or by attempting difficult journeys – sometimes all three! This is our nature and we shouldn’t shy away from it. But we should also recognize that “going there” is just one of the ways in which we can explore the cosmos. Modern telescopes can see almost to the visible edge of the Universe, the Large Hadron Collider can probe scales much smaller than the nucleus of an atom. I worry sometimes that the political lobbying for manned space flight often seems to be arguing that it should be funded by taking money from other, more fundamental, scientific investigations. Astronomers and particle physcisists are explorers too, and they also inspire. Don’t they?

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