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Thanks Dominic.
You are likely correct about the WHT. I just assumed it might be trying to look at the sky without actually checking on its current status.
Travel to and from La Palma is straightforward for fully vaccinated European citizens. SWMBO and I had no problem getting there in late June and coming back the UK required us to have PCR tests before and after the flight this week. Passenger location forms were required by both the Spanish and UK governments. The tourist industry is recovering and accommodation levels are about 80% at peak; most visitors are from Germany and The Netherlands, but that has long been the case.
Kevin’s all-sky camera is reporting a light dusting of ash at Tacande.
The INT and NOT (at least) are not opening up tonight because of ash in the air. Not yet head about the WHT and GTC.
Eruption now becoming quite explosive. Pyroclasts reaching 300m in altitude according to my rough and ready observations and trigonometry.
Certainly much noisier and brighter tonight, though the noise is mostly coming in pulses and the background roar is noticeably lower.
Now that more information is becoming available I have been able to pinpoint the location of the eruption to within a few metres. As best I can make out, it is at latitude 28°36’54″N, longitude 17°52’02″W which is 3.2±0.1 km almost due south of here. (Here being Tacande Observatory which is labelled on Google Maps.)
The view is quite impressive after dark but the volcano has caused no trouble at all for Kevin and me as yet.
The location is very close to this point in Google Maps:
https://www.google.es/maps/@28.6154215,-17.8670681,268m/data=!3m1!1e3?hl=en
Absolutely typical. Politicians always like to come rubber-necking when something mildly interesting occurs.
Further, they invariably promise that help and monetary compensation will be made available instantly. True in this case too.
There is still a very noisy pillar of hot ash visible from the window next to where I am typing.
It is a bit noisy and we have Bortle 9 skies to the south at present. I now have some more images and a few videos which are perhaps of interest.
Ah well. It all adds a modicum of interest to an otherwise tedious existence.
Incidentally I, SWMBO and two in-laws were stuck in La Palma for several days when Mount Unpronounceable erupted in Iceland a few years aback and closed down almost all European airspace. That one definitely increased the sky background brightness and reduced the transparency in the UK.
It is noisy and there is a wonderful illustration of the old saying: Red sky at night, vulcanologists’ delight but everything else is just fine. The camera has lost its cooling (as has Kevin’s in the neighbouring dome) so we wouldn’t be observing anyway but otherwise there is no good reason not to open up the domes.
This one is taken within 3 minutes of the start of the eruption. My dome is to the left, Kevin’s to the right, largely hidden by the tree.
“provided the directions are indicated”. A very very important point. Thank you for drawing it to our attention.
I understand the reasoning behind why planetary images are generally shown “upside down” but (with one major exception) most everything else these days is displayed with north to the top and east to the left. Look at any major atlas, either on paper or on-line, and it will follow this convention. As far as I can tell, most images in the BAA gallery are similarly aligned though, to be sure, some are not but those exceptions seem to show no particular pattern.
My own images are generally N-up, E-left but that is primarily because that is the result of SWarp’s stacking algorithm rather than any conscious choice of mine. The raw subs are at whatever angle the camera happened to be at the time but a single sub is rarely of much use except perhaps for photometry where the angle and parity doesn’t matter for reporting purposes.
Now the major exception;: M31. Images generally appear East-up & South-left or NE-up & SE-left. My favoured explanation is that some people prefer to see the galaxy in a landscape view rather than portrait. Hubble’s famous frontispiece to The Realm of the Galaxies adheres to the N-up & E-left convention.
Does the absence of C, O, etc, indicate that the progenitor star was of relatively small mass and so significant He burning hadn’t started before it lost its hydrogen envelope in the red giant phase?
Or does it mean that all the heavy material has sunk into the core and that convection is insignificant?
I’d love to. My last attempt was 2021-09-01 and taken through thin cloud. Not so thin, actually, as I needed several 1-minute exposures to get anything measurable. It would normally take a single exposure of somewhere between 2-5 seconds.
Clouds even thicker since then with the same forecast for several days. I hope UK observers have better luck.
The 2021-09-01 observation will be processed and uploaded RSN, honest guv.
Everything went well with the installation, though sudo was needed to complete the installation as expected.
However, when run the code crashes with
ImportError: cannot import name ‘ImageTk’ from ‘PIL’ (/usr/lib/python3/dist-packages/PIL/__init__.py)
There was lots more diagnostic output which can be provided on request.
Anyone any ideas? I’ve contacted the Exoclock team but without any response so far.
There has been some speculation that it may have been a Venus Trojan in the past. It seems that Venus Trojans aren’t stable on gigayear timescales, largely due to perturbations by the Earth, but may well be metastable for a good number of megayears.
Thanks Richard. I will try to have a go next March. The elongation is 40 to 50 degrees that month if I read the MPC ephemeris correctly.
I am still missing some of the long-published but out of print volumes. as I collect books, I will doubtless pick up the entire series if and when the volumes become available.
Good point about Dorado, etc, but robotic observatories are becoming rather popular …
Publications by Willmann-Bell should become available again within a few months. The news report is at https://aas.org/press/aas-acquires-willmann-bell-titles
One interesting snippet reads: The AAS also plans to publish new volumes in the popular Annals of the Deep Sky series; Volume 8 is already printed and bound and will be available for immediate shipment once we begin accepting new orders.
Although I stated I can reach 20.5 in 51.5 minutes on a decent night, tonight was not decent with poor seeing and ok-ish transparency some of the time. The killer, though, was intermittent thin cloud going by. Not yet had chance to go through the subs and through out the particularly bad ones. I had difficulty imaging (50000) Quaoar at V=18.9 in 102 minutes. Most certainly not helped by it being 3 arcseconds away from a star which is 0.7 magnitudes brighter.
An image may appear on my personal page eventually but it will not be pretty.
That is very impressive! I also love how the vibrational structure of the telluric molecular bands is so well resolved.
Thanks Richard.
To be honest, the possibility of occultations had completely skipped my mind. This is probably because I have never tried observing one because I am not geared up for accurate timing on a cadence of several Hertz. Unfortunately there are no TNO occultations predicted for here until after I return to the UK.
(174567) Varda, (225088) Gonggong, (145452) 2005 RN43 and (50000) Quaoar are all reported by the MPC as having 3 variant orbits available with discrepancies between them of up to 3 arcsec though are also status 1. They are mag 20.2, 21.4, 19.9 and 18.9 respectively. (523692) 2014 EZ51 is status 4 and mag 21.5 right now.
Incidentally, why are TNOs et al. ordered by H in the Handbook? It would seem to me to be more useful for observers if they were ordered by opposition date or magnitude.
