Forum Replies Created
-
AuthorPosts
-
Jeremy ShearsParticipant
Great stuff, Max.
Jeremy ShearsParticipantProbably flickering, as you suggest Max. All very interesting
Jeremy ShearsParticipantChanges in periods of Miras is a very active field of research as it might shed further light on stellar evolution in the Asymptotic Giant Branch (AGB) of the HR diagramme. One popular view is that period decrease is due to contraction during the initial stage of the thermal pulse in the helium burning shell, as you indicate.
Another period changer is T UMi. Coincidently there is an MRAS pre-print on ArXiv only today on “Hydrodynamic modelling of pulsation period decrease in the Mira-type variable T UMi” which pursues the matter. It considers hydrodynamic models and non–linear stellar pulsations. The references therein are worth following: https://arxiv.org/abs/2206.08360
Keeping up with ideas and literature in this area could be a fulltime job, but we are lucky to have the monthly AGB Newsletter to help us as it summarises recent literature. You can subscribed to it here: https://www.astro.keele.ac.uk/AGBnews/
The June edition is the 299th, and celebrations are promised for the July edition. It is available here: https://www.astro.keele.ac.uk/AGBnews/issues/AGB299.pdf
The last chapter on this fascinating topic has yet to be written! But it is interesting to note that the research, and the associated models, depend on amateur observations of Miras over many years.
Jeremy ShearsParticipantNo problem submitting, Max. Researchers can subsequently apply any data quality selection criteria they wish. Without any data they have no choice. The other consideration is that your data, at the very least, provide a snapshot of the system status at that time.
Jeremy ShearsParticipantThose data really are incredibly tight, Max!
Jeremy ShearsParticipantMultiple confirmations of the eruption have appeared overnight. Appears to be around maximum (8th mag).
In the 2010 eruption, it faded one mag in a day and 6 mags in 4 days. Let’s hope we get a break in UK skies (I’ve not seen any UK obs yet)
Jeremy ShearsParticipantCharts here: https://app.aavso.org/vsp/chart/?star=U%20SCO&fov=60&maglimit=14.5&resolution=150&north=up&east=left
Can be scaled/orientated to choice
Jeremy ShearsParticipantMaehara-san (Okayama, Japan ) reports U Sco at mag 9.2 on
Jun 6.773Jeremy ShearsParticipantThanks Max. Good to see you back!
Jeremy ShearsParticipantGreat stuff – thanks Max
Jeremy ShearsParticipantNot sure Max. Does the main dip coincide with the time when an eclipse should have occurred?
Jeremy ShearsParticipantSuper – many thanks Max. All very interesting indeed.
Jeremy ShearsParticipantImpressively tight data, Max!
Jeremy ShearsParticipantWorth looking for quiescence eclipses, Max. Accretion disc might be smaller then and thus more easily eclipsed
Jeremy ShearsParticipantYes, mag is certainly consistent with an outburst Max
Jeremy ShearsParticipantThis nova is still being observed and still relatively bright at 11th mag. Worth following. What will it do next?
Light curve from the VSS database:Attachments:
Jeremy ShearsParticipantThanks Max. When I have a moment I’ll put it through Peranso to see if there are any signals.
Jeremy ShearsParticipantThanks Max. There’s a lot of variation there. Not sure it’s regular though. Time will tell.
Keep up the good work!Go well!
JeremyJeremy ShearsParticipantWonderful to see the video of this well deserved honour for Alan – thanks for sharing, James.
Jeremy ShearsParticipantStarlight Nights is available on Kindle, Daryl. Not the same as having the book, but at least you can enjoy it and be reminded why we love astronomy so much.
I think I was 14 when I first read it. Our Eng Lit master said we should read a book of our choice (“not a textbook on astronomy, Shears!”) and write about it afterwards. I found it in the village library. I must have renewed its loan many times. And fortunately it’s not textbook.
-
AuthorPosts