Archive for Euclid

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.

From Einstein to Euclid: the Gallery

Posted in Biographical, Maynooth, The Universe and Stuff with tags , , on September 11, 2023 by telescoper

Last week I posted a photograph taken during my public lecture at Maynooth University. I thought I’d compound your collective misery by putting up more. I’m not sharing any pics of the audience because we didn’t ask them for permission, so you’re basically stuck with pictures of me (and one of Joost Slingerland, our Head of Department, in the first one).

Thanks to Dale for taking the pictures!

The Universe from Einstein to Euclid

Posted in Biographical, Talks and Reviews with tags , , on September 7, 2023 by telescoper

As we head into the Day 2 of the ITP2023 I thought I’d share the slides I used for the public talk I gave last night. We had an audience of around a hundred which wasn’t bad given that it is graduation week and the undergraduates aren’t back!

Here is the abstract used to advertise the talk:

Euclid is the name of a new scientific mission from the European Space Agency, launched on July 1st, designed to explore the composition and evolution of the Universe. The Euclid mission takes its name from the ancient Greek mathematician regarded by many as the Father of geometry. Until the last century, Euclid’s theorems were assumed not just to be mathematical notions, but to describe the geometrical structure of the physical Universe. Einstein’s general theory of relativity swept that idea aside and gave us new ways of describing space, by unifying it with time, and by allowing it to be affected by matter in a manner very different from that formulated by Euclid. Over the past century, this theory has proved to be very effective at describing the properties of the Universe as observed by modern astronomical telescopes, while also suggesting the existence of dark matter and dark energy.

The Euclid telescope will create an enormous map of the large-scale structure of the Universe across space and time by observing billions of galaxies out to 10 billion light-years, across more than a third of the sky. Euclid will explore how the Universe has expanded and how galaxies and clusters of galaxies have formed over cosmic history, and how space itself is distorted by these structures.

This talk will discuss our modern ideas of space and time, how the Euclid mission will try to test whether or not they are correct and shed light on the nature of dark matter and dark energy.

And here are the slides:

Obviously I cut a number of long stories very short, which probably contributed to why I had a lot of questions from the audience at the end of the talk. I always assume that’s a basically a good sign because it shows people are interested, but it also makes me worry that I didn’t explain things very well!

We didn’t finish until past 9 o’clock and it was a very warm evening, so I was very happy to have a few pints afterwards in O’Neills…

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.

The Challenges of Large Collaborations in STEM

Posted in Biographical, Harassment Bullying etc, Mental Health with tags , , , , , on August 12, 2023 by telescoper

There’s a new paper on the arXiv by Kamiel Janssens and Michiko Ueda that addresses some of the challenges that arise for people working in large STEM collaborations. Although the sample they use is drawn from gravitational-wave collaborations I think many of the patterns that emerge will also apply elsewhere, e.g. in the Euclid Consortium.

Here is the abstract:

Large-scale international scientific collaborations are increasingly common in the field of STEM (Science, Technology, Engineering, and Mathematics). However, little is known about the well-being of the members participating in these `big science’ collaborations, which can present unique challenges due to the scale of their work. We conducted a survey among members of three large, international collaborations in the field of gravitational-wave astrophysics in the summer of 2021. Our objective was to investigate how career stage, job insecurity and minority status are associated with reported levels of depressive symptoms as well as the desire to leave academia. We found that early-career scientists and certain minoritized groups reported significantly higher levels of depressive symptoms compared to senior members or those who do not consider themselves as a member of minoritized groups. Furthermore, relatively young members, staff scientists/engineers, and those experiencing high levels of job insecurity and lack of recognition were more likely to frequently consider leaving academia. Our findings suggest that improving recognition for personal contributions to collaborative work and providing clearer job perspectives could be two key factors in enhancing the well-being of young scientists and reducing the potential outflow from academia.

arXiv:2308.05107

I would like to add a personal note. When I was an early-career researcher in cosmology I was for the most part given a free hand to work on whatever I wanted to do. My first papers were either sole author or with one or two others, being people I’d met and wanted to collaborate with. Nowadays many opportunities – indeed, most – for postdocs are associated with very large teams into which one just has to fit. The work is also highly directed with little choice of what to do, and it is harder to individuals to shine even if the team is well managed, and not all senior scientists in such collaborations have good leadership skills. Theoretical astrophysics is challenging enough but sometimes the really difficult thing is the behaviour of other people!

I’m not saying that this way of working is necessarily bad, just that it is very different from what I experienced. It does not therefore surprise me to hear that many, especially younger, people struggle in the current environment and why it is important for large collaborations to do the best they can to help. I think part of that involves us oldies recognizing that things are very different now from what they were like back in our day.

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.