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New Results from Euclid

Posted in Euclid, Maynooth, The Universe and Stuff with tags , , , , on May 23, 2024 by telescoper

As it was foretold, exciting new results from the European Space Agency’s Euclid mission have now been released.

You can read more about these images here.

Together with the five images released last November that makes a total of ten Early Release Observations from the pre-survey phase of Euclid. It’s not all about the pictures, however. Today also saw the release of ten scientific papers to go with these images, as well as five reference papers for the main survey. You can find them all, with accompanying information here. They will be announced on arXiv tomorrow.

You might also be interested to read my Euclid piece on RTÉ Brainstorm which has just appeared. This is not just about the new images, but gives an update on what Euclid has been up to since launch, and what we can expect in the future. There’s also a version adapted for Maynooth University PR purposes here. It includes this quote:

Today’s release of new data and technical papers from Euclid is exciting in itself but also marks the start, after months of painstaking calibration and testing of the instruments, of Euclid’s main cosmological survey. We are on the threshold of a new era in cosmology. Maynooth is the only University in Ireland to be involved in this mission and it is very exciting to be at the forefront of such an important scientific development.

I’m also quoted in a piece in the Irish Times. You’ll probably find the article blocked by a paywall but my bit is:

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Gearing up for Thursday’s Euclid News

Posted in Euclid, Maynooth, The Universe and Stuff with tags , , , , , , , on May 21, 2024 by telescoper

It’s a hectic time ahead of a Big Event on Thursday 23rd May, which will include the publication of five new Early Release Observations (EROs). I’m not at liberty to say what they are until after 12 noon (CEST) on Thursday except that they’re very pretty. You can watch the live stream here:

Including the five released on November 7th 2023 that will bring the total to ten. All the ERO pictures will be available on the ESA archive here.

Thursday will also see the release of ten scientific papers related to the EROs; they will appear on arXiv on Friday 24th May. These will be the first science results from the Euclid mission.

But that’s not all! Thursday will also see the publication of five papers from the Euclid Consortium (of which I am the sole member based in Ireland). These will be the principal technical reference papers aimed at the astronomical community about the Euclid mission, covering the instruments, cosmology and other astronomy science possibilities, as well as the cosmological simulations used to assist the analysis of the mission. One of these, the main overview paper for the mission, has over a thousand authors (one of whom is your truly).

Thursday’s announcements are likely to significant level of press interest. That’s not only due to the European Space Agency’s own social media feeds and the like, but also local activities in Ireland. For example, there’s this from Science Foundation Ireland using this, from the Little Book of Irish Research:

I have also written a piece for RTÉ Brainstorm, as a kind of update on the one I wrote last year on the occasion of the launch; this will go live after the embargo is lifted on Thursday.

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Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , on May 18, 2024 by telescoper

It’s time once more for the usual  Saturday roundup of business at the  Open Journal of Astrophysics. The latest batch of publications consists of three papers, taking the count in Volume 7 (2024) up to 39 and the total published by OJAp up to 154. We’re still on track to publish around 100 papers this year, compared to last year’s 50.

All three of this week’s papers involve use of data from the European Space Agency’s Gaia mission, which is proving an immensely rich resource for astrophysics.

First one up is “Asymmetric Drift Map of the Milky Way Disk Populations between 8 -16 kpc with LAMOST and Gaia datasets” which is by  Xin Li (Nanchong, China), Peng Yang (Chengdu, China) , Hai-Feng Wang (Nanchong, China), Qing Li (Jiangmen, China), Yang-Ping Luo (Nanchong, China), Zhi-Quan Luo (Nanchong, China), Guan-Yu Wang (Nanchong, China). This is a study  of the asymmetric drift, the difference of the local circular speed and the mean rotational speed of the stellar population, for various stellar populations in the Milky Way. It is in the folder marked Astrophysics of Galaxies and was published on Tuesday 14th May 2024.

Here is a screen grab of the overlay, which includes the abstract:

 

 

You can read the paper directly on arXiv here.

The second paper to announce is “On the formation of a 33 solar-mass black hole in a low-metallicity binary” by Kareem El-Badry (Caltech, USA). It discusses theoretical models for the formation of a black hole in a particular binary system discovered in Gaia data.

This one is in the folder Solar and Stellar Astrophysics and was published on 16th May 2024. The overlay looks like this:

 

 

You can read this paper directly on the arXiv here.

The last paper of this batch, also in the in the folder Solar and Stellar Astrophysics, is entitled “Compact Binary Formation in Open Star Clusters II: Difficulty of Gaia NS formation in low-mass star clusters”  and it presents a discussion of the formation of binary neutron stars and black holes found in Gaia data based on their orbital properties. It was published on Friday May 17th 2024 (i.e. yesterday). The authors are Ataru Tanikawa (Fukui University, Japan), Long Wang (Sun-yat Sen University, China) and  Michiko S. Fujii (Tokyo University, Japan).

Here is a screengrab of the overlay:

 

 

To read the accepted version of this on the arXiv please go here.
That’s all for now. Another update next week!

 

 

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Examination Time in Maynooth

Posted in Barcelona, Education, Maynooth, The Universe and Stuff with tags , , on May 17, 2024 by telescoper

Today ( Friday 17th May) is the first day of the Summer Examination Period in Maynooth. Although I’m not there right now I thought I’d take the opportunity to wish all students the best for their examinations:

You shouldn’t really be relying on luck of course, so here are some tips for the examination period (especially for physics students, but applicable elsewhere).

  1. Try to get a good night’s sleep before the examination and arrive in plenty of time before the start. Spending all night cramming is unlikely to help you do well.
  2. Prepare well in advance so you’re relaxed when the time comes.
  3. Read the entire paper before starting to answer any questions. In particular, make sure you are aware of any supplementary information, formulae, etc, given in the rubric or at the end.
  4. Start off by tackling the question you are most confident about answering, even if it’s not Question 1. This will help settle any nerves. You’re under no obligation to answer the questions in the order they are asked.
  5. Don’t rush! Students often lose marks by making careless errors. In particular, check all your numerical results on your calculator at least twice
  6. Please remember the units!
  7. Don’t panic! You’re not expected to answer everything perfectly. A first-class mark is anything over 70%, so don’t worry if there are bits you can’t do. If you get stuck on a part of a question, don’t waste too much time on it (especially if it’s just a few marks). Just leave it and move on. You can always come back to it later if you have time.

Meanwhile, in Barcelona, Monday is a public holiday (Pentecost) so I am faced with the prospect of having to endure a long weekend break. Such is life…

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The Radio and Microwave Sky from Juno

Posted in The Universe and Stuff with tags , , , , , , , on May 16, 2024 by telescoper

I found out about an interesting paper by Anderson et al. at a discussion group this morning. The abstract reads:

We present six nearly full-sky maps made from data taken by radiometers on the Juno satellite during its 5-year flight to Jupiter. The maps represent integrated emission over ∼4% passbands spaced approximately in octaves between 600 MHz and 21.9 GHz. Long time-scale offset drifts are removed in all bands, and, for the two lowest frequency bands, gain drifts are also removed from the maps via a self-calibration algorithm similar to the NPIPE pipeline used by the Planck collaboration. We show that, after this solution is applied, residual noise in the maps is consistent with thermal radiometer noise. We verify our map solutions with several consistency tests and end-to-end simulations. We also estimate the level of pixelization noise and polarization leakage via simulations.

arXiv:2405.08388

For those of you unaware about Juno, it is a NASA space mission (launched in 2011) intended to study the planet Jupiter (which it is still doing). On the way there, however, this spacecraft made continuous measurements of the radiation field around it, at radio and microwave frequencies. The work described by Anderson et al. involved turning these observations into maps at a range of frequency; they also studied the polarization properties of the radiation.

The full maps and other relevant data can be downloaded here. Here are some pretty pictures (the grey bits represent the parts of the sky that were not covered; radio emission from our own Galaxy is the most obvious component at low frequencies, but it looks more complicated at higher frequencies).

It’s always fun when data sets are used for something so different from the purpose originally intended, and what has come out of this analysis are rather nice maps of the emission from the Milky Way. These might turn out to be useful for many things, such as foreground removal for extragalactic surveys or studies of our own Galaxy.

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R.I.P. Jim Simons (1938-2024)

Posted in R.I.P., The Universe and Stuff with tags , , , , , on May 13, 2024 by telescoper

I heard yesterday of the death, at the age of 86, of Jim Simons. Jim Simons started out as an academic in the fields of mathematics and mathematical physics. Together with Shiing-Shen Chern he developed the Chern–Simons form, which has been of interest recently in the context of cosmology because of the potential for parity violation, and also contributed to the development of a theoretical framework to combine geometry and topology with quantum field theory. He then moved to into the world of hedge funds, and became a highly successful investor on Wall Street, amassing a huge personal fortune. In later life he turned back to his first loves, however, and set up the Simons Foundation which supports, among many other things, the Simons Observatory and the Flatiron Institute both of which have had, and will no doubt continue to have, an enormous impact in the fields of cosmology and astrophysics. The Simons Foundation has also made large donations to the arXiv.

R.I.P. Jim Simons (1938-2024)

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Night of the Aurora

Posted in Biographical, Maynooth, The Universe and Stuff with tags , , , , , on May 11, 2024 by telescoper

My social media feeds have been buzzing all day with images of last night’s display of the Aurora Borealis (and Australis) resulting from a large solar storm. I saw some great pictures from Ireland, including many from Maynooth and environs. I really liked this one taken from one of the ships of the Irish Naval Service:

I also saw pictures of the Aurora Borealis from the UK (even as far South as the Midlands), USA and as far South in Europe as Marseilles, not to mention New Zealand (Aurora Australis).

It’s not that unusual for the Northern Lights to be visible from Ireland, but it is extremely rare to see them from Catalonia. They were visible last night from Sabadell, just a few km North of Barcelona, though not as far as I know in Barcelona itself. I didn’t see anything, but I was otherwise engaged. The Observatory at Montsec Astronomical Park recorded the strongest level of Auroral activity for 150 years.

Auroral activity seen from Sabadell, picture credit Albert Segura Lorrio

All this reminds me that many moons ago, I once stood directly under an auroral display, in Tromsø (Norway), and I can tell you ever the word “awesome” applied to anything, this was it. The curious thing is that I had the definite feeling that there was a booming and whooshing sound to go with the light show. I wasn’t the only one there who thought they could hear it as well as see it. And I wasn’t drunk either. Well, not very.

Whenever I asked anyone about the sound my questions were dismissed on the grounds that there is no physical mechanism that could produce sound waves at audible frequencies of sufficient power to reach ground level from the altitude at which the light is generated. It must have been psychological, as if the brain wants to add a backing track when it sees something as spectacular as this. However, read at least one researcher is not so sure…

Comments are welcome through the usual box.

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Four New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , on May 11, 2024 by telescoper

It is time yet again for an update of recent activity at the Open Journal of Astrophysics.
This week we have published four papers, which I now present to you. These four take the count in Volume 7 (2024) up to 36 and the total published by OJAp up to 151. I speculated last week that we would probably pass the 150 mark this week, and so we did. We’re still on target to publish around 100 papers this year.
In chronological order, the four papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.
First one up is “Ephemeris Matching Reveals False Positive Validated and Candidate Planets from the K2 Mission” by Drake A. Lehmann (U. Wisconsin-Madison, USA) and Andrew Vanderburg (MIT, USA). It presents a description and application of a technique for identifying false positives among candidate exoplanets. The paper was published on 7th May 2024, is in the folder marked Earth and Planetary Astrophysics, and can be found here.
Here is a screen grab of the overlay, which includes the abstract:


You can find the officially accepted version of the paper on the arXiv here.
The second paper to announce is “Accuracy requirements on intrinsic alignments for Stage-IV cosmic shear” which is by by Anya Paopiamsap, Natalia Porqueres & David Alonso (Oxford, UK) and Joachim Harnois-Deraps & C. Danielle Leonard (Newcastle, UK). This paper sets about quantifying the permissible level of disagreement between the true intrinsic galaxy alignments and the theoretical models thereof that can be allowed for future Stage-IV cosmic shear surveys. This one is in the folder marked Cosmology and Nongalactic Astrophysics. The paper was published on May 9th 2024 and you can see the overlay here:


The accepted version of this paper can be found on the arXiv here.
The next paper, is in the folder Instrumentation and Methods for Astrophysics and is entitled “Optimal Summary Statistics for X-ray Polarization”. The authors are Jeremy Heyl (Uni. British Columbia, Canada), Denis González-Caniulef (Uni. Toulouse, France) and Ilaria Caiazzo (Caltech, USA). This presents new statistical estimators for use in studies of X-ray polarization, with an analytic discussion of their efficiency. It can be found here and the accepted version can be read on arXiv here. Here is the overlay:

The last paper of this batch is called “B-modes from galaxy cluster alignments in future surveys” and is by Christos Georgiou, Thomas Bakx, Juliard van Donkersgoed and Nora Elisa Chisari, all from Utrecht University in The Netherlands. It presents a discussion of the possible detection of cosmic shear B-modes produced by intrinsic alignments in future galaxy surveys.
Here is the overlay:

You can find the full text for this one on the arXiv here. The primary classification for this one is Cosmology and Nongalactic Astrophysics.
And that ends this week’s update. More next week!

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Publishing Stats for Astrophysics Journals

Posted in Open Access, The Universe and Stuff with tags , , , , , on May 6, 2024 by telescoper

Somebody asked me about this recently so this afternoon while I was paying rapt attention to a Zoom call I was attending I did some quick sums and produced the table below. The request that was made was to give details of total numbers of papers published in the big astronomy and astrophysics journals last year. This is easy relatively easy to do using the excellent NASA/ADS search tool.

Name of JournalNumber of PapersNumber of CitationsAverage citations per paper
MNRAS413125,5406.18
A&A235415,9016.75
ApJ285915,7715.52
ApJL72610,22814.09
ApJS3382,6117.72
OJAp503717.42
Citations to papers published in 2023 (Data from NASA/ADS)

In case you weren’t aware of the standard abbreviations, MNRAS is Monthly Notices of the Royal Astronomical Society and A&A is Astronomy and Astrophysics; ApJ is the Astrophysical Journal, ApJL is the Astrophysical Journal Letters and ApJS is the Astrophysical Journal Supplement Series. The Open Journal of Astrophysics is OJAp.

Anyway, you can see that the big journals published many more papers last year than OJAp but in terms of citations per paper OJAp is doing well. We have a lot of ground to make up if we’re going to be a significant player in the game in terms of sheer quantity of publications, but since we don’t make a profit from APCs we have no reason to lower standards to achieve that.

If you’re interested, the average citations per paper so far this year (i.e. as of 6th May 2024) are: MNRAS (1.84); A&A (1.66); ApJ (2.29); ApJL (2.05), ApJS (2.09) and OJAp (2.90).

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Two New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, The Universe and Stuff with tags , , , , , , on May 4, 2024 by telescoper

It’s Saturday morning in Barcelona, and time to post another update relating to the  Open Journal of Astrophysics.  Since the last update we have published two more papers, taking  the count in Volume 7 (2024) up to 32 and the total published by OJAp up to 147. There’s every chance we will reach 150 next week.

The first paper of the most recent pair – published on  Monday 29th April- is “Supernovae in 2023 (review): possible breakthroughs by late observations” by Noam Soker of Technion in Haifa, Israel. It presents  a discussion of observations of the aftermath of supernovae explosions, such as supernova remnants, and how these may shed light on the explosion mechanism. This one is in the folder marked High-Energy Astrophysical Phenomena.

Here is a screen grab of the overlay which includes the abstract:

 

You can click on the image of the overlay to make it larger should you wish to do so. You can find the officially accepted version of the paper on the arXiv here.

The second paper was published on Thursday 2nd May and has the title “ΛCDM is alive and well” The authors are: Alain Blanchard (Université de Toulouse, France), Jean-Yves Héloret (Université de Toulouse, France), Stéphane Ilíc (Université Paris-Saclay, France), Brahim Lamine (Université de Toulouse, France) and Isaac Tutusaus (Université de Genève, Switzerland). This one, which is in the folder marked Cosmology and NonGalactic Astrophysics, presents a review of  review of the alleged tensions between observations and the standard cosmological model.

I did a post recently relating to a Royal Society Meeting on this topic. The first version of this paper appeared on arXiv about two years ago but the final version is extensively modified.

Here is a screen grab of the overlay which includes the abstract:

 

 

You can click on the image of the overlay to make it larger should you wish to do so. You can find the officially accepted version of the paper on the arXiv here.

And that concludes this week’s update. More next week!

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