Archive for the Euclid Category

The Little Book of Irish Research

Posted in Euclid, Maynooth, The Universe and Stuff with tags , on November 18, 2023 by telescoper

Yesterday, the last day of Science Week, saw the launch by Simon Harris TD, Minister for Further and Higher Education, Research, Innovation and Science, of the Little Book of Irish Research. This book, which is aimed at school students, so is written at an elementary level, gives quick summaries of areas of research that the general public said that they were interested in, grouped into sixteen themes, and it will be distributed to schools all round Ireland.

I was very gratified to see myself get a mention (on page 41), though it’s not really about me but about Euclid which has generated considerable interest in the general public already and is set to continue doing that for many years. As you can see, there’s also a double-page spread of JWST, though unfortunately it does not name the scientists involved; Paddy Kavanagh is the main man at Maynooth for matters JWST.

I understand The Little Book of Irish Research will be the focus of a social media campaign over coming weeks, which will hopefully make more people more aware of the research going on in all disciplines in Ireland. I think we’ll find it useful for our own outreach events, open days, etc, in the Department of Theoretical Physics, and so will the many colleagues in other Departments whose work is also featured.

I haven’t seen hard copies of the book yet, as I’m in Barcelona, but if you want to read it here is a PDF file of the whole thing for you to download at your leisure.

Euclid, the Perseus Cluster, and Beyond!

Posted in Euclid, The Universe and Stuff with tags , , , on November 8, 2023 by telescoper

I see that the Euclid Early Release Observation of the Perseus Cluster is today’s Astronomy Picture of the Day:

The Perseus Cluster seen by Euclid

The Perseus Cluster (Abell 426) – a dense concentration of over a thousand galaxies with a total mass of about 1.2 × 1015 M⊙ – is impressive in its own right, especially because the picture was taken in a single exposure, but the staggering thing about this image is that it contains hundreds of thousands of galaxies. In other words there are as many galaxies in this picture as there are words in a book. Most of these galaxies are in the background, not associated with the cluster, and many of them extremely distant. With so many objects in one field, you can perhaps see how much data we will get from the entire survey, which will last more than 6 years. It is these distant sources – billions of them – that Euclid will survey to glean information about the expansion history of the Universe.

P.S. Yesterday’s press conference resulted in a lot of media attention worldwide, even some in Ireland. There is a piece on the RTÉ website, for example, and another on Silicon Republic (which includes a quote from yours truly).

Euclid Early Release Observations

Posted in Euclid, The Universe and Stuff with tags , , , , , , , , on November 7, 2023 by telescoper

So today’s the day. The first science-quality observations from Euclid have now been released to the public. The official press release is here, and the press conference showcasing the new observations can be viewed here:

The images themselves can be found in this repository. In summary they are (in no particular order):

  1. Galaxies in the Perseus Cluster
  2. Spiral galaxy IC 342
  3. Irregular galaxy NGC 6822
  4. Globular cluster NGC 6397
  5. The Horsehead Nebula

And here they are – you can click on them to make them bigger:

A few points of my own.

First, it is important to realise that these observations are not part of the full Euclid survey, which will start in early 2024, but were produced during the process of verification the capabilities of the telescope and detectors. They are all very short exposures, taking up less than a day to make all the images, but they demonstrate that Euclid is performing very well indeed!

Euclid is designed to achieve very sharp optical quality across a very wide field of view, so its strength is that it will produce beautiful images like these not only of a handful of objects but for billions. We need to map very large numbers of galaxies to perform the careful analysis needed to extract information about dark matter and dark energy, which is the main goal of the mission.

While these images are, in a sense, by-products of the Euclid mission, not specifically related to the main aims of the mission, they are interesting in their own right and there are proper scientific papers related to each of the five sets of observations released today. We expect many more non-cosmological spinoffs like these as the mission goes on.

There were some problems during the commissioning of the instruments carried by Euclid, the most serious of which was an issue with the Fine Guidance Sensor used to control the pointing of the telescope. This has been fixed by a software update and everything is now functioning well, as today’s new results confirm!

Euclid Update!

Posted in Euclid with tags , , , on November 6, 2023 by telescoper

Just one more sleep before the first actual science images from European Space Agency’s Euclid mission are released tomorrow. These are called the Early Release Observations (EROs) – they aren’t part of the full survey, but are to demonstrate the performance of the telescope and detectors.

There has been a slight change to the schedule advertised here so the press conference will now take place on Tuesday 7th November at 14.15 Central European (not Summer) Time, CET, which is 13.15 GMT. For more details, see here.

You can watch the press conference on the new ESA Web TV channel or on the Youtube Live Stream. I’ll post a quick update tomorrow after the images go public.

Preparing for Euclid’s First Images

Posted in Euclid, The Universe and Stuff with tags , , , on November 3, 2023 by telescoper

Another quick update about the release of the Early Release Observations (EROs) from Euclid, due to take place next Tuesday 7th November. For one thing, here is a little taster video.

Five images will be released on Tuesday. I know what the Early Release Observations are but you will have to wait until Tuesday to find out. If I told you now I’d have to kill you…

Euclid Update!

Posted in Euclid with tags , , , on October 30, 2023 by telescoper

Just a quick post to give advanced notice that, gremlins in the pointing system having been dispelled, the first actual science images from European Space Agency’s Euclid mission will be released on Tuesday 7th November at 14.00 Central European (not Summer) Time, CET. These are called the Early Release Observations (EROs) – they won’t be part of the full survey, but are just to demonstrate the performance of the telescope and detectors.

You can watch the press conference on the new ESA Web TV channel. I’ll post more about the EROs after they become public, but not before.

Euclid Update

Posted in Euclid, The Universe and Stuff with tags , , , , on October 7, 2023 by telescoper

Having settled in to my new apartment on the Gran Via I’ve got time for a another quick update on the European Space Agency’s Euclid mission. For full details about what follows you can see here. Everything I mention here is already in the public domain, so I am not disclosing any secrets!

The last update I posted contained some frustrating and potentially worrisome news: the Performance Verification (PV) phase of the mission had to be put on hold in order to troubleshoot an intermittent problem with the Fine Guidance Sensor (FGS), which is supposed to help to maintain correct pointing of the telescope. This wasn’t working correctly as demonstrated vividly by the following image:

Obviously the survey couldn’t proceed without accurate control of the pointing of the telescope so it was urgently necessary to find out what was going wrong and fix it. It turns out that the software was getting confused by the flashes caused by cosmic ray protons hitting the detectors, think they were the gude stars it was supposed to be steering by. After identifying the problem, new software was written and uploaded to the spacecraft.

I wasn’t sure how this had gone until I saw via an internal communication that the PV phase had restarted. That announcement would not have been made had the upgrade not worked and sure enough it has now been made public that all is well. Congratulations to the instrumentation and software teams for this success. They’ve been working phenomenally hard on this.

There was an additional problem with stray light in the telescope that I have also mentioned before. That was only an issue for specific orientations of the telescope and has been dealt with by simply redesigning the survey a little to minimize the occurrence of the effect.

So the gremlins have been dispelled, and we go on into the PV phase after a delay of about a month. The survey is due to last 6 year so this hiccup is not a big deal really. We can in fact anticipate some early science results from this phase in a month or so, although they will not be part of the full survey which will start after the PV phase is complete, after a few months.

Euclid Update

Posted in Euclid, The Universe and Stuff with tags , , , , on August 27, 2023 by telescoper

Time for a quick update on the European Space Agency’s Euclid mission. For full details about what follows you can see here. Everything I mention here is already in the public domain, so I am not disclosing any secrets!

The last update I posted mentioned that Euclid had moved into what is called the Performance Verification phase of its mission. That has now been put on hold in order to troubleshoot an intermittent problem with the Fine Guidance Sensor (FGS) which helps to maintain correct pointing of the telescope. This issue can probably be fixed by software updates, but these will have to be tested, hence the pause. This is rather irksome, but the instrument teams are confident they can find a solution soon.

Anyway, while we’re waiting, here is a video from Launch Pad Astronomy explaining about the mission. It was actually released about six days ago but I didn’t have time to post it until now. About 15 minutes long, it’s a big longer than previous official Euclid videos I’ve posted, but I think it’s very informative:

Oh, I almost forgot to mention that I’ll be talking a little bit about Euclid among other things at this event on 6th September.

Euclid Update

Posted in Euclid with tags , , , , , on August 15, 2023 by telescoper
ESA/Euclid/Euclid Consortium/NASA. Background galaxies: NASA, ESA, and S. Beckwith (STScI) and the HUDF Team.

Since I’ve been working today on stuff related to ESA’s Euclid mission, I thought I would post a brief update on the mission status before I go home. The official channel to which I refer you for full updates is here.

A message was sent out on Saturday to member of the Euclid Consortium indicating that the commissioning phase of the Euclid satellite was essentially completed, although with some issues still to be fixed. In particular, as has previously been reported, there is an issue with stray light in the VIS instrument, which will have to be coped with. To prevent stray sunlight getting onto VIS detectors, Euclid will be configured to operate at a range of specific angles with respect to the Sun. This means that the survey strategy will have to be adapted in order to be as optimal as possible with this new constraint.

The next phase after the commissioning phase is called performance verification, for which control switches over to the science ground segment. The operations team will then operate the spacecraft in the same way as required for the full survey in order to assess the performance of the instruments and obtain calibration data ahead of the start of the full survey.

How Euclid will map the Universe

Posted in Euclid, The Universe and Stuff with tags , , on August 10, 2023 by telescoper

Time for another nice little video explainer about Euclid. This one is largely about the role of large computer simulations (particularly the Flagship simulation) in preparing for (and in future in analyzing) the Euclid survey.

The full blurb accompanying the video is appended here:

ESA’s Euclid mission will create a 3D-map of the Universe that scientists will use to measure the properties of dark energy and dark matter and uncover the nature of these mysterious components. The map will contain a vast amount of data, it will cover more than a third of the sky and its third dimension will represent time spanning 10 billion years of cosmic history.

But dealing with the huge and detailed set of novel data that Euclid observations will produce is not an easy task. To prepare for this, scientists in the Euclid Consortium have developed one of the most accurate and comprehensive computer simulations of the large-scale structure of the Universe ever produced. They named this the Euclid Flagship simulation.

Running on large banks of advanced processors, computer simulations provide a unique laboratory to model the formation and evolution of large-scale structures in the Universe, such as galaxies, galaxy clusters, and the filamentary cosmic web they form. These state-of-the-art computational techniques allow astrophysicists to trace the motion and behavior of an extremely large number of dark-matter particles over cosmological volumes under the influence of their own gravitational pull. They replicate how and where galaxies form and grow, and are used to predict their distribution across the celestial sphere.

Explore the Euclid Flagship simulation in this video and get a sneak preview of the structure of the dark Universe, as we currently model it. New insights will be brought to you by the Euclid mission in the coming years.