Archive for the The Universe and Stuff Category

A Pembrokeshire Dangler

Posted in Biographical, Maynooth, The Universe and Stuff on November 28, 2021 by telescoper

I checked the weather app on my phone last night and noticed the unmistakable cloud formation over the Irish Sea known as a Pembrokshire Dangler:

The Dangler is the strip of rain  over the Irish Sea extending North from the Pembrokeshire coast in Wales. I knew I had mentioned this phenomenon before on this blog and when I check it turns out to have been almost exactly four years ago. That’s not very surprising as winter is definitely the season for dangling. There has been a northerly airflow over Ireland for a few days now, which is why it has been so cold here, though in relatively sheltered Maynooth we have been spared the worst of the effects of Storm Arwen.

The situation required for the formation of a Pembrokeshire Dangler (which quite often involves snow rather than rain) is a cold northerly airflow down into the Irish Sea from the Arctic. This combines with slightly warmer air in the form of land breezes from the Irish coast to the North West and the Scottish coast to the North East, funneling the airflow into a narrow channel over the Irish Sea in which convection cells form, leading to precipitation. The configuration is quite stable as long as the dominant northerly airflow continues so although the strip of cloud tends to persist for some time once it has formed.

A Free Online Course in Cosmology from SISSA

Posted in Education, The Universe and Stuff with tags , , , , on November 25, 2021 by telescoper

The nice people at the Scuola Internazionale Superiore di Studi Avanzati (known to its friends as SISSA for short) have made available a free online course in cosmology. You can get all of it on Youtube.

The course comprises 16 professionally edited video-lectures delivered by lecturers of the SISSA Astrophysical and Cosmology and Astroparticle PhD Programs and some of their collaborators. I know some of the participants personally, including Paulo Salucci (who introduces the course though I haven’t met him in person for ages so it was nice to see him on camera.

Cosmology is a big subject, of course, and a short-ish course can’t cover everything so there is an emphasis on the research topics covered by SISSA scientists. I haven’t watched all the videos but those I have seen are pretty good. There are actually 17 videos in the playlist below but that includes a very short prelude to introduce the series. The others are between about 25 and 45 minutes in length so you probably don’t want to watch them all in one sitting!

Clusters and Superclusters of Galaxies 1991

Posted in Biographical, The Universe and Stuff with tags , , on November 23, 2021 by telescoper

As part of an occasional series of blasts from the past down memory lane of days gone by I present this, which was taken in Cambridge in July 1991 – 30 years ago!!! – at the NATO ASI Clusters and Superclusters of Galaxies:

Picture Credit: Alberto Fernandez Soto

There are no prices for putting names to faces because the names are all along the bottom but it’s still fun to try doing it without looking at the answers!

The Curious Incident of the JWST and the Clamp Band…

Posted in The Universe and Stuff with tags , , , on November 23, 2021 by telescoper

 

Just a quick newsflash to pass on the news that the launch of the James Webb Space Telescope has been pushed back until at least 22nd December 2021 owing to an “incident” that occurred during preparations for its launch.

It seems the sudden release of a “clamp band” – or is it band clamp? – caused unwanted vibrations through the observatory and it now has to be thoroughly checked before it can be declared safe for launch.

This is not the news anyone wanted to hear, but the previous launch date was 18th December, so hopefully the few days’ delay won’t cause too much difficulty.

I was going say that for JWST to work there has to be something incident on its mirror, but on reflection I decided that wasn’t a very good joke.

 

 

Astrophysics & Cosmology Masterclass – The Video!

Posted in Education, Maynooth, The Universe and Stuff, YouTube with tags , , , on November 15, 2021 by telescoper

As promised here is the video recording of the Astrophysics & Cosmology Masterclass we held by Zoom last Friday.

That Was The Masterclass That Was

Posted in Education, Maynooth, The Universe and Stuff with tags , , , on November 12, 2021 by telescoper

This morning we did the Astrophysics and Cosmology Masterclass advertised here. I think it went quite well. Apparently we had over sixty schools registered – at least one in every County – about a 1,000 schoolkids altogether. Certainly there were lots and lots of questions, which is a good sign!

Here is a screen grab of part of the event. I didn’t realize my camera was a bit wonky!

In case anyone is interested here are the slides I used for my part of the talk:

I’ll post a recording of the whole event when it becomes available. Here is the recording of the workshop:

I had to leave before the end to go to a vector calculus lecture that was interrupted by the arrival of the Power Rangers, but that’s a different story…

New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , on November 5, 2021 by telescoper

Time to announce yet another publication in the Open Journal of Astrophysics. This one is the 14th paper in Volume 4 (2021) and the 45th in all.

The latest publication is entitled  Ultra Fast Astronomy: Optimized Detection of Multimessenger Transients, and is in the section marked Instrumentation and Methods for Astrophysics.  The authors are Mikhail Denissenya of Nazarbayev University (Kazakhstan) and Eric V. Linder of the University of California at Berkeley (USA).

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

You can find the paper on the Open Journal of Astrophysics site here and can also read it directly on the arXiv here.

The 2020 Decadal Survey

Posted in Science Politics, The Universe and Stuff with tags , , on November 4, 2021 by telescoper

Delayed by a year, the 2020 US Decadal Survey of Astronomy -full title Pathways to Discovery in Astronomy and Astrophysics for the 2020s – is now out.

It’s a hefty document of more than 600 pages so I haven’t had time to do anything but skim it. The top priority for NASA for the next decade seems to be a 6-m class space telescope capable of imaging Earth-like worlds orbiting sun-like stars, something that can’t be done with much larger telescopes from the ground though the plan does involve bringing very large ground-based telescopes (the Giant Magellan Telescope in Chile and the Thirty Metre Telescope in Hawaii) into service more quickly than currently scheduled. Any new space telescope won’t be built and launched on the timescale of course: it probably won’t fly until the 2040s by which time I’ll probably be retired,

I also noticed in the section on the Cosmic Microwave Background we have

Recommendation: The National Science Foundation and the Department of Energy should jointly pursue the design and implementation of the next generation ground-based cosmic microwave background experiment (CMB-S4).The panel suggests that third-generation CMB experiments aligned with CMB-S4―specifically, the SPO (South Pole Observatory) and the “nominal” version of the SO (Simons Observatory)―be high priorities for federal support.

The clarifications in parentheses are my additions.

The shopping list is a lot longer than these items however. There is plenty of discussion in the media already. See, for example, here. I may comment further if time allows.

UPDATE: there is a very user-friendly interactive overview of the survey here.

This is of course an American survey but Astronomy is a truly international enterprise so astronomers all round the globe will be studying it and trying to work out its implications for their own research environment.

And of course there’s a box below for comments from you!

Astrophysics & Cosmology Masterclass at Maynooth!

Posted in Biographical, Education, Maynooth, The Universe and Stuff with tags , , on November 4, 2021 by telescoper

Regular readers of the blog – both of them – may remember that, after a couple of postponements due to Covid-19, we presented a Masterclass in Astrophysics & Cosmology in Maynooth on March 25th 2021. Well, owing to popular demand, we’ve decided to do a re-run of the event on Friday 12th November 2021 ahead of the forthcoming CAO cycle. That’s a week tomorrow!

This will be a half-day virtual event via Zoom. It’s meant for school students in their 5th or 6th year of the Irish system. There might be a few of them or their teachers who see this blog so I thought I’d share the news here. You can find more information, including instructions on how to book a place, here.

Here is the updated official poster and the programme:

I’ll be talking about cosmology early on, while John Regan will talk about black holes. After the coffee break one of our PhD students will talk about why they wanted to study astrophysics. Then I’ll say something about our degree programmes for those students who might be interested in studying astrophysics and/or cosmology as part of a science course. We’ll finish with questions either about the science or the study!

I’m told that with a week still to go we already have over 750 science students based in schools from An Daingean to Arranmore Island, from Monaghan to Mayo and many counties in-between. Fortunately it is online so no travelling is involved. Unfortunately the participants don’t get to see the wonderful campus so here’s a gratuitous picture!

(And at 12 noon I don’t turn into a pumpkin but do have to run off to give a lecture on vector calculus..)

A Question of Balance

Posted in Cute Problems, The Universe and Stuff with tags , , on November 3, 2021 by telescoper

Here’s an interesting physics problem for you, based on the idea that the mass of a set of bodies changes if the energy of their mutual interactions changes according to Einstein’s famous formula “E=mc2“.

Four identical masses are placed at rest in pairs either side of an extremely sensitive balance in a symmetrical way such that the distance between the members of a pair is identical for each pair and the centre of mass of each pair is equally spaced from the fulcrum of the balance. In this configuration the system is in equilibrium and the balance is level.

As illustrated schematically in the graphic, one pair of weights is adjusted by displacing each weight slightly away from the centre of mass of the pair by an equal and opposite distance, thus keeping the position of the centre of mass of the pair constant. The other pair of weights is not adjusted.

Assuming that the balance is sufficiently sensitive to detect the slight change in mass associated with the gravitational interactions between the masses in each pair, does the balance move?

If it does move which pair moves up: the displaced pair or the undisturbed pair?