Disturbing the Universe

David L Clements, science and science fiction


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Press Release: Four new galaxy clusters take researchers further back in time

I have a press release out today! Below is the text from the release from Imperial. So far it seems to have been picked up by:

The Daily Mail

The Financial Express

The Economic Times

Phys.Org

scientias.nl (in Dutch)

and there may be more to come.

Not sure what to think about the Daily Mail entry – it’s not my favourite paper, but, as a colleague said, ‘if your piece is next to “Lauren Goodger shows off the results of her new boob job in unflattering sheer dress at charity event” and “What happened to natural beauty, Kim? Kardashian overdoes her look with thick, heavy make-up arriving at Khloe’s house” you’re certainly reaching new audiences.’

News: science

Imperial College London

Four new galaxy clusters take researchers further back in time

by Gail Wilson12 February 2014

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Four unknown galaxy clusters each potentially containing thousands of individual galaxies have been discovered some 10 billion light years from Earth.

An international team of astronomers, led by Imperial College London, used a new way of combining data from the two European Space Agency satellites, Planck and Herschel, to identify more distant galaxy clusters than has previously been possible. The researchers believe up to 2000 further clusters could be identified using this technique, helping to build a more detailed timeline of how clusters are formed.

– Dr Dave Clements

Study author

Galaxy clusters are the most massive objects in the universe, containing hundreds to thousands of galaxies, bound together by gravity. While astronomers have identified many nearby clusters, they need to go further back in time to understand how these structures are formed. This means finding clusters at greater distances from the Earth.

The light from the most distant of the four new clusters identified by the team has taken over 10 billion years to reach us. This means the researchers are seeing what the cluster looked like when the universe was just three billion years old.

Lead researcher Dr David Clements, from the Department of Physics at Imperial College London, explains: “Although we’re able to see individual galaxies that go further back in time, up to now, the most distant clusters found by astronomers date back to when the universe was 4.5 billion years old. This equates to around nine billion light years away. Our new approach has already found a cluster in existence much earlier than that, and we believe it has the potential to go even further.”

The clusters can be identified at such distances because they contain galaxies in which huge amounts of dust and gas are being formed into stars. This process emits light that can be picked up by the satellite surveys.

Galaxies are divided into two types: elliptical galaxies that have many stars, but little dust and gas; and spiral galaxies like our own, the Milky Way, which contain lots of dust and gas. Most clusters in the universe today are dominated by giant elliptical galaxies in which the dust and gas has already been formed into stars.

“What we believe we are seeing in these distant clusters are giant elliptical galaxies in the process of being formed,” says Dr Clements.

Observations were recorded by the Spectral and Photometric Imaging Receiver (SPIRE) instrument as part of Herschel Multi-tiered Extragalactic Survey (HerMES). Seb Oliver, Head of the HerMES survey said: “The fantastic thing about Herschel-SPIRE is that we are able to scan very large areas of the sky with sufficient sensitivity and image sharpness that we can find these rare and exotic things.  This result from Dr. Clements is exactly the kind of thing we were hoping to find with the HerMES survey”

The researchers are among the first to combine data from two satellites that ended their operations last year: the Planck satellite, which scanned the whole sky, and the Herschel satellite, which surveyed certain sections in greater detail. The researchers used Planck data to find sources of far-infrared emission in areas covered by the Herschel satellite, then cross referenced with Herschel data to look at these sources more closely. Of sixteen sources identified by the researchers, most were confirmed as single, nearby galaxies that were already known. However, four were shown by Herschel to be formed of multiple, fainter sources, indicating previously unknown galaxy clusters.

The team then used additional existing data and new observations to estimate the distance of these clusters from Earth and to determine which of the galaxies within them were forming stars. The researchers are now looking to identify more galaxy clusters using this technique, with the aim of looking further back in time to the earliest stage of cluster formation.

The research involved scientists from the UK, Spain, USA, Canada, Italy and South Africa. It is published in the Monthly Notices of the Royal Astronomical Society.

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Waking Up

Yes, it has been a bit quiet around here of late. Summer holidays happened, with a nice long weekend spent at the Moseley Folk Festival, and then ten days working on our friends’ ‘croft’ on the lovely Isle of Skye.

But all good things come to an end, and term starts in a bit less than a week, so it’s time to wake up.

Things that have happened in physics of late that are of interest include a new way to calculate particle interactions in particle physics that use a geometric object dubbed the amplituhedron. If correct it will be massive.

I’ve also got a rather interesting paper close to acceptance by the journal. More news on that when it’s done.

There will also be news on an exciting new writing project for me very soon, I hope!

And just to get things started interestingly for the new academic year, I had an impacted wisdom tooth removed today. I’m still at that stage where the surgery has been done but the local anaesthetic has yet to wear off. Fingers crossed that it doesn’t get too painful.

I’m off to a Planck meeting tomorrow, so the dental surgery will make things rather interesting, though maybe not more painful, knowing how these meetings tend to go.


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Royal Society Show

Some people seem to think that academics don’t do anything in their long ‘vacations’. I think I’d quite like to go back to term term, as I’ve pretty much been non-stop ever since term ended at the end of June.

The main reason for this, and for my absence from these pages, is that I was running the Planck stand at the Royal Society Summer Science Exhibition. This is a week long extravaganza, where scientists from about 23 selected teams show off their science to the public using exhibition stands set up in the Royal Society’s building, just off the Mall. I’ve been part of shows before, most recently last year’s Herschel exhibit, but this was the first time I had run a stand. The experience of being in charge is very different!

Things that were new to me, at least with respect to running the stand, was sorting the budget, ordering piles of stuff from many different people, getting artwork sorted from our excellent graphic designer and much more. The most stressful, from my point of view, was ensuring that everything we needed was going to be there on time. Mostly this worked, and, at the end of the Sunday before the exhibition opened, we had a stand.

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I think we had one of the nicest stands, though I would say that. We had the centrepiece, which is a 1/4 scale model of Planck, we had videos running above, a Planck version of Chromoscope running around the side of the stand to the right, some examples of flight hardware in a display box, two touchscreens running appropriate games/demos, one of which can be found here, and even a telephone where you can dial up the sound of the Big Bang!

We also had lots of freebies – pens, fridge magnets, bookmarks, leaflets, and even papercraft models of Planck to cut out and build. All of those even arrived on time. However, what was meant to be the piece de resistance did not arrive on time. I ordered small inflatable beachballs with the Planck CMB map printed on them. I was promised delivery the Friday before the exhibition opened and they did not turn up. They also didn’t turn up on the Monday or Tuesday. By the Wednesday, my first full day away from the stand since it started, I was on to the suppliers playing – well not exactly Dr Angry, but certainly Dr Disappointed.

It turned out that the company was disappointed too, since our universes, and several other customers’ orders, were unaccountably being held by HMRC for no readily apparent reason.

They didn’t turn up until the Monday after the show had ended, and there are some production problems with them as well as the delivery issue. Still, some novel uses have already been found for them…

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This is what happens when graduate students get to play with too many universes!

Despite the lack of beach balls, the show went very well. This is what was left of the stand late into the packing up process, as we awaited the van to collect the model.

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According to the Royal Society we had over 11000 people through the front door, and a further 30000 who looked at our web material during the show, and you can still look at the stuff on the web.

The visitors were very varied, from 5 year olds to Fellows of the Royal Society and everything in between, so you have to think on your feet when answering questions. It was a lot of fun, but exhausting to be in charge. I’ll happily stand aside so that someone else can have that pleasure next time.


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Planck Day!

Things are, as you would imagine, busy. My colleague, Andrew Jaffe, is off to Channel 4 in half an hour, and a posse of Planck scientists is sitting in our coffee room watching presentations from Paris.

The ESA pages on the Planck release are here, and BBC coverage can be found here.

And if you want to play with the Planck maps yourself, I can recommend the Planck Chromoscope.

Bottom line of the results from my point of view: the era of precision cosmology has arrived!

More will accrete over the next few days.


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Planck: Release Details

No – not the content of the release, that’s still embargoed, but how you can watch the press conference yourself…

This is what I’ve been told are the arrangements for Planck Day, Thursday 21 March:

There is an ESA Press Conference in Paris from 9am UK time, with talks from the ESA Director General and George Efstathiou. There will be a simultaneous press event at the RAS here in London which will stream the Paris talks, and will be followed by a panel discussion and Q&A featuring Andrew Jaffe (Imperial), Mark Ashdown (Cambrdige), Richard Battye (Manchester), Anthony Challinor (Cambridge), Jo Dunkley (Oxford), Steve Gratton (Cambridge), Paul Shellard (Cambridge) and Locke Spencer (Cardiff).

There will also be an afternoon session in Paris with more technical talks.

Both morning and afternoon Paris talks will all be streamed at http://www.esa.int.

Papers will be up on the ESA site at about noon Thursday, and on astro-ph Friday morning.


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Planck: The Teaser Trailer

As you all already know (and if you don’t you’ve not been paying attention to this blog!), the first Planck cosmology results are coming out on 21st March.

Just to make sure absolutely everybody knows this is going to happen, ESA have produced a trailer. Go and watch it now…

I think this is the first time there’s been a teaser trailer for a set of scientific results. I don’t think even the LHC did that.

And as for the cod 70s soundtrack? Sounds more appropriate for a Shaft movie to me. The possibilities for remixes are endless…