Welcome to the Volcano Café bar, a place for all things on or off topic and inane ramblings. There has been a need of late to find a place better suited to various theories, long comments and enthusiasm. This page will be less moderated than the main article pages and cleared out every month (this may change depending on use).
Have fun and don’t forget to tip the barman 😉
HVO has released a couple of videos of the lake taken by the drones at https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_chronology.html
While I was watching it I was thinking we might be giving too much importance to the lake when what actually matters is what is around and below.
Capture from the video:
And a closer look:
The material inside the crater consists of gravel and huge boulders, fridge-sized probably falls short for some of those, all of this is highly permeable meaning that the lake is just a tiny expression of the amount of water actually stored in there and availiable for phreatomagmatic interaction. This volume of water would help explain while earlier phreatomagmatic eruptions of Kilauea came in groups, an eruption was probably not enough to overcome the water so it seems to have always taken a couple of them to drive the water away.
The groundwater may also extend down a considerable distance
Hey does anyone know if this signal is meaningful?
https://www.bbc.co.uk/news/world-europe-50603284?intlink_from_url=https://www.bbc.co.uk/news/science_and_environment&link_location=live-reporting-story
opening up a year old topic… my 7.1 earthquake in Alaska (skipping the discussion if it was Anchorage’s or Wasilla’s here is a map of the shaking found recently which pictures why even tho i was many road miles from the earthquake it still shook strongly at my house … hope this works
nope didn’t copy… nevermind….
https://twitter.com/AKearthquake/status/1200557688557461505/photo/1
Were you in one of the areas with ‘severe’ shaking?
i was in one of the bright yellow blobs to the south… shaking was strong but this is a rickity old house and vibrated pretty good. nails popped out of sheetrock and some doors don’t close now and some cracks in walls but everything was still standing. Just pointing out that one can be close to the epicenter but still hundreds of road miles away when large bodies of water are needed to circumnavigate. We are celebrating a year later here with news reports etc. Hope everyone is ok in the bar.. i’ve been busy getting old(er)… Happy Winter everyone! and for the moment (will change tomorrow) there is green grass in the yard…. :O… Best!motsfo
Pyroclastic flow reported on Shishaldin volcano, Alaska. The image below was taken on Nov 26 and shows the debris. The summit itself is (as usual) not visible. Two days later the debris field appears covered in snow again.
My wife and i are looking to buy a home weather station. Any suggestions? We live at 7500 feet elevation in the Colorado front range. Winds are capable of gusting above 100 mph, so the wind gauge need to be particularly robust.
Contact your local weather bureau / USGS office ? They’ll have a fair idea of what won’t blow apart or away, and what will still work without de-icing power…
Oregon Scientific do a good range of weather stations from under $100 to over $300.
If you want the better quality, take a look at Davis Instruments weatherstations. Bit more expensive, but robust stuff.
Itsa…
Itsa…
https://www.cgtrader.com/free-3d-models/exterior/landscape/mountainous-terrain-icelandic-4k
Yes, of course, it is a mountain but, in Iceland, they’re *all* volcanic !!
Seriously, is this edifice recognisably modelled ??
FWIW, I’m on the hunt for a nice, low caldera, a mini-me version of Yellowstone with modest lake, geo-thermal field, perhaps a few fumaroles. A dormant flank cone with a sun-facing lava tube would be handy…
😉
Question/remark for the dragons.
The bar has rowed up quite some replies now in one article. To refresh the page it takes 25 seconds or more now.
Could you launch a new article here, to solve that waiting problem? (I guess I am not the only one that stares at a wall, pondering away the time….⏳)
The plan was to delete the comments regularly. Later we felt that it would be a pity to loose so an archival solution was looked at. That was the state a play a while ago. Time to reconsider, I guess
You could just put up a nice poster on the wall to look at while waiting?
It’s something that I discussed with Tommy a while back and we were going to look at archiving it and then starting afresh. It’s something that slipped our busy minds I’m afraid. I’ll discuss it with him again.
I usually look at this site once a day. It is my treat with tea after dinner. What I do is use the Find function and look for the current date, for example 5/12. Since the hour offset is 8 for the Washington state area I may miss some posted message which have, for me, tomorrow’s date but I get to see them the next day. If I need context for the comment I am reading, I just scroll up. If you are reading the comments throughout the day it may not work but for me it makes it much easier to find the new comments.
been dealing with a dump (more than a foot) of snow/ power outages as trees fall across the lines/ and now cold dips towards 0F so i’m just sending my Best! to everyone who makes the boards interesting.. i’m still here just quiet(er) 😉
New post is up! Ambrym – in memoriam
https://www.volcanocafe.org/ross-at-ambrym/
A lot of activity at Mauna Loa today
There is some rain, but it is chugging along. Looking at the South Hawaii radar HWA you can see rain moving in two different directions depending on the level. Upper level winds from the west, and low level winds from the east with both air flows supporting precipitation.
Kilauea and Nyiragongo are the most fluid sillica based lavas
I have Nyiragongo viscosity now
Its generaly 60 Pa.s ( in current lava lake )
Thats very low
And some papers for Kilaueas
halemaumau says 20 to 30 Pa.s
As halemaumau was extremely fluid
Kilauea range from above 100 Pa.s in East rift zone
to to 40 down to 10 Pa.s at the summit arera
2008 – 2018 lava lake was generaly 40 Pa.s
Hawaiian lavas can be down to 10 pa.s In some cases
Whats the viscosity for Nyiragongo 1977 eruption?
I cannot find the data on that one
I knows that Nyiragongo 1977 is saied to be the most fluid sillica based eruption ever seen
Eruption at Semisopochnoi reported this morning
All
Why does the HVO report the small earthquakes in the Kilauea area? I understand that this is one of the most observed/monitored volcanoes ever and the instrumentation is fabulous….. I guess my question is what could be gained from looking at and recording the wave form of a .52 mag quake reported at a depth of .63 km (with errors of Vertical / Horizontal Error:0.3 km / 0.15 km).
I have filtered the list of quakes to show only the <1 magnitude on the list but others are shown on the map. The IRIS wave form is included after the map. This is for the .5 at .6km quake that is second on the list which sits in the deepest area of the new caldera.
2019-12-01 22:56:53 0.9 9.6
2019-11-26 09:12:11 0.5 0.6
2019-11-26 08:55:56 0.6 0.7
2019-11-26 07:38:34 0.8 1
2019-11-26 07:38:32 0.7 1.7
2019-11-26 07:37:53 0.4 1
2019-11-26 07:26:02 0.4 0.8
2019-11-26 06:58:24 0.9 1.3
2019-11-26 06:09:03 0.4 1
Let me know, enjoy the weekend
Mac
Most small earthquakes are not reported though, I am not sure why some of them do make it sometimes. The past week, month, year data page shows the 0 and 1 magnitude earthquakes and most of these are not later catalogued.
They are still important because these small ruptures often happen in the walls of the magma chambers and reflect the pressure state of the volcano.
These are a volcanic signals right? They do look kind of strange. (I will DEFINiTELY give 1 million dollars to whoever guess what volcano this. HINT: it is not cerro negro)
Ecuador….
Pululahua
Last erupted 467 BCE…
Damn it! What gave it away? (remind of this incident so i can give you the money when become famous.
“PULU HHZ” kind of gives it away 🙂
I shall wait patiently, Tallis! You do have the advantage that I am already 60… 🙂
The quakes at Askja have moved from the rift zone past the volcano to the inner caldera fault. They are very small, but it is an interesting change
https://www.thesun.co.uk/news/10511437/new-zealand-eruption-white-island-tourists-dead/
We received a rather abusive email apparently blaming me for the White Island events: “people like you promoting volcano tourism should be held responsible for what just happened you are an ignorant dangerous censored“. Anonymous, of course, although it isn’t that difficult to find out who send it. We are happy to host civilized and well-argued discussions. For everything else, the ‘be nice’ rule applies.
Nothing is wrong with showing just how nasty you can be. We all have a little sociopath in us(or is that just me?)
Albert
This is an extremely reasonable, well run and educational site. All the posts and posters seek to expand knowledge and always highlight the risks and hazards from volcanic activity, eg GLs ‘do not be there’ rule etc
To me, the writer of the email is ignorant and either delusional or a troll.
To all at VC, please keep up the excellent work and don’t let the odd ‘critic’ outweigh the (100’s, 1000’s?) of us who enjoy the site and rarely comment but only due to having essentially nothing much to add.
Hear hear!
What a sad thing to happen, Albert. I trust it was not sent by one of our community.
If anything, the knowledge gained from this wonderful community has precisely the opposite effect. From all I have learnt here, there’s no way I would go near a live volcano! Education brings wisdom.
I follow a facebook page that gives regular reports about the state of things at Gunung Agung. It strives to give accurate and educational information in order to mitigate any false rumors that might be spreading. That page often gets angry messages from people who think that the page is scaring tourists away from Bali. Apparently, volcano blogs are to blame both for attracting tourists and also for scaring them away…
I hope you don’t take that nonsense to heart. Over the last 9 years I haven’t seen anything that encourages risk taking around volcanoes. I am mindful of Lurking’s sage advice about avoiding trouble in dangerous places – Don’t be there!
Albert, you should show them your inner satan to such insulting (insert expletive). And make them understand why don’t F&*( with a smart person.
Talking about volcanic hazards…
Nyiragongo is an infamous one!
Located in the slow spreading continetal albertine rift. And feed by very small ammounts of partial melting deep down.
Infamous for its permanent lava lake.
Nyiragongo is unique: nowherelse in the world does a simple steep sided perfect stratovolcano, contain a magma column of souch extremely fluid hot, sillicate lava.
Nyiragongo is an Nephelinite with 35% sillicon and max 1250 C. The magma is extremely alkaline and very sillica poor.
This makes nyiragongos lava extremely insanely fluid! also combined with the very steep slopes. As long as the magma remains as a lava lake in the summit all is fine.
The dangers with Nyiragongo is the rifting and draining of the lava lake magma column.
Dangerous with a high magma column almost 3 kilometers above sealevel: imagine the hydrostatic pressure it puts on the edifice.
The 1977 Nyiragongo eruption.
In 1977 Nyiragongo burst open and the Nephelinite came rushing out!
Extremely fluid lava poured down through the flanks and minutes got to settlements kilometers away. Eyewitness suggest flowing of between 70 km/h and 100 km/h and the flow passed the forests at such a speed that it did not set fire to the trees and even left some thicker leaves with a thin glassy layer. Ground deposits were blue black glass at places only a centimeter thick.
Numerous persons , mostly the elderly or children, coud not escape from the flows. Exact numbers of victims cannot not be confirmed. Although the official count was 74, it is belived that maybe 400 people may have died. The lava flood covered persons with a thin glassy caparace including an elephant herd where all killed by the lava flood.
Elephants encased in black blue lava glass.
Around 20 million cubic meters of very degassed magma from the upper lava lake conduit were erupted in an hour, after which the eruption stopped instantly. An eruption rate around 6000 cubic meters per second was estimated. The driving force was primarily the hydrostatic pressure of magma in the upper 1000 m of the lava lake conduit located above the main vents. Lava spatter found in trees around the fissure vents testify to violent fountaining caused by the absoutley extreme pressure exerted by the magma column at the onset of the eruption.
Beyond phreato-magmatic burps, I’d thought ‘ordinary’ pyroclastic flows / nue Ardentes were top of the volcanic ‘Oh, Sh**t’ list for *sudden* immolation. Mt St Helens-style flank collapse, their extreme form.
The way a braw pyroclastic flow may run out across open water and/or produce a non-trivial phreato-magmatic event as seen at eg Montserrat is definitely a ‘Be Not There’.
I get shivers thinking about those volcanic African lakes, whose effusive over-turn quietly, quietly suffocates their neighbours. I’m so glad the ‘usual suspects’ now have ‘soda fountains’ in place…
But, being caught by a flash-flood of molten glass– Now, that is scary !!
==
FWIW, saw an interesting comment on how to identify tsunami experts or volcanologists. They park near road exit, facing it, so won’t need to back&turn, risk grid-lock…
IIRC, this small precaution has become formalised via warning signs at vulnerable beaches on NW US / Canadian coast.
Nik yes
Nyiragongo is extremely scary with its steep slopes and insanely fluid 1250 C ultrabasic lava.
On the volcanos slopes its impossible to outrun.
This volcano poses unique hazards from molten rock.
In 1977 and 2002 humans and animals and lifestock alike became covered in thin shells of Nephelinite glass as Nyiragongo erupted from its flanks… 400 000 homes gone too in 2002
Nephelinite is an insanely rare sillicate rock and is produced in the smallest ammounts globaly.
Nyiragongo is the only permanently active Nephelinite volcano in the entire world.
Since 2003 it hosts a permanent lava lake at the summit
It was impossible to escape/ outrun in 1977
The Nephelinite lava flood lasted under an hour
And killed maybe as many as 400 persons.
Cattle and elephants covered in glassy lava shells
The lava was so hot and fluid it flowed like water
Temperatures for 1977 have been estimated to be considerabely higher than 2002.
1370 C have been estimated for 1977 upper vents at Nyiragongo.
These estimations are unclear and theory I think.
But if they are true it makes this the hottest lava eruption ever recorded
Nyiragongo is unique…
Only stratovolcano in the world with souch an extremely fluid sillica poor magma.
Its worlds largest lava lake again after halemaumau drained in 2018…
Been soon 30 years of uneasy peace in that region in Congo and Goma is growing rapidly
Tourism is increasing too to Nyiragongo as Virunga National Park welcomes vistors.
Nyiragongo remains extremely dangerous as a volcano with flank eruptions possible in middle of one of Africas larger cities.
In 2002 around 400 000 homes where destroyed as a fissure opened up right inside the city. Lava flooded the city. The fatality was lower than 1977 but still many perished
Nyiragongo might be capable of putting out even larger amounts of the super-fluid lava. Maybe even larger than 2002 and 1977 combined. I remember having watched a documentary on TV about this volcano way back in the early 2000s, where a Belgian volcanologist was saying to the press that Nyiragongo managed to dish up HUGE amounts of that kind of lava over a very large area some several centuries ago. If true, then this must’ve been truly terrifying to the local people in the area. Today, there’s a heck of a lot more people living the local area. Goma’s population is now about 2 million. That is a lot more than in 2002, when the last outpouring entered this city. There was only about 400,000 at the time, and definitely less in 1977. If such a catastrophic lava flood on the scale that scientist mentioned happened today, this could be very, very catastrophic.
The lava is indeed extremely fluid
A Nephelinite with 35% sillica and over 1200 C
But its probably not very more fluid than halemaumaus thoelites ( Kilauea is extremely fluid specialy at the summit )
Nyiragongo and Kilauea are similar temperatures at the summit
Kilauea is higher sillica
but the high 1250 C temperature at the summit breaks down the basalt sillica polymers and makes kilauea just as fluid as Nyiragongo at the summit.
10 Pa.s been measured for halemaumau.
Nyiragongo is extremely fluid and aided by the very steep slopes of that paticular volcano.
Hawaii and Congo are the most fluid sillicate based lavas
Mike K, Albert
Nyiragongo arera is up for a scary geological future!
The ultrabasic super – alkaline volcanism of Nyiragongo and Nyiramuragira .. is just the start of something much larger…
For millions of years it was just passive rifting in Albertine area rift ( thats why you haves these incredibely deep rift African freshwater lakes )
But in Western East African Rift there is now a ominous boulge growing ( 700 km wide ) and have risen the Nyiragongo arera more than a kilometer higher than sourrounding areras.
( birthing plume head ) still rising
The region around the Virunga volcanoes is uplifted over 1.6 km above sea level, leading to no small amount of theory that the rifting and volcanic activity, is runned by a local mantle plume beneath the region. The mantle plume is around 600 km wide.
At the start ( now ) partial melting is very low and gives rise to highly alkaline rift volcanism like Nyiragongo and Nyiramuragira
( for their strong alkanity these two volcanoes are very productive )
The mantle plume likley not surfaced yet.
The future
In the future the mantle there will continue to head up and the plume head will start to decompress generating enormous ammounts of thoelitic basalt…
When that arera really gets going you gets the next LIP flood basalt event there?
Partial melting will increase alot as the continetal rift opens up more.
The arera around Nyiragongo is ripe for a large basalt igneous province outbreak as the rifting progressess.
But the Thoelitic basalts haves not emerged yet as partial melting at current is far too small.
You never ever finds any highly alkaline flood lavas ..
The partial melting under Virunga thats these days very very low
Will go into overdrive in the future IF the mantle plume really surfaces
Then you gets Basalt
Todays very small ammounts of partial melting deep down, is resposible for Nyiragongos Nephelinites
Latest repost 16 december 2019
Nyiragongos lava lake continues to rise and overflows from the lava lake and flows from still active 2016 cone continues to fill up the caldera
The lava levels ( lava layers ) have now reacted platform 2 basicaly the magma column is now as high as it was in 1977
Platform 2 is the crater floor before it collapsed in 2002, if I remember right Platform 1 would be the level before the 1977 collapse. The lava lake still has to raise about 80 m to reach the 1977 level.
Tallis Rockwell: you knew about this volcano before right?
Nyiragongo is crazy stuff and since 2003, it hosts the largest lava lake in the world at its summit.
Nowherelse in the world, does a steep sided stratovolcano, contain souch a hot fluid low sillicate lava. Nyiragongos sillica content is down to just 35%!
( Hawaii is 50% )
I am well aware of Nyiragongo, in fact I want to write an article about the east african rift and it’s foreboding potential but cerro negro distracted me with it’s explosive potential, I am a felsic man after all.
Nyiragongo is absoutley crazy sillicate magma! just 33 to 36% sillicon
Really really insanely fluid and hot
If the sillica ain’t high then imma fly!
But in all seriousness highly fluid magma like that has only grabbed my attention recently. After researching Icelandic systems, I have found a new respect for mafic and other low viscosity magma.
Most Icelandic magmas are thoelitic basalts and general sillica content of 50%
Nyiragongo is only 35% sillicon
Making it extremely fluid
Extremely sillica -undersaturated mafic igneous rocks souch as Nyiragongo are much less abundant than silica-saturated and oversaturated normal basalts.
Nyiragongos Nephelinites are acually formed by very small ammounts of partial melting in the Albertine Rift
Very deep down too. Nephelinite are among those magmas thats made in the smallest ammounts.
Nephelinite are even more sillica poor than komatites
But prehistoric komatites are result of very large ammounts of partial melting.
The current active Nyiragongo Nephelinite magma series are products of very small ammounts of melting in earths mantle.
https://m.youtube.com/watch?v=Ky9Wd9evO4I
One of the most beautyful Nyiragongo videos
I wish I was there on the craters edge… looking down into this enormous lava lake…
Nothing else is more beautyful the colours are amazing.
This reminds me of Mordor
Nyiragongos lava lake is almost as wide as 3 football fields now… in 2020.
The youtube video of Nyiragongos lava lake was recorded some years ago now .. even then Congos lava lake was huge …
I’m one who abides by Lurk’s “don’t be there.” putting three mountain ranges
away and several gigatons of basalt under me-from the Oregon coast…
http://hraun.vedur.is/ja/vatnajokulsvoktun/grf_uppsafn.html
Looks like Grimsvötn is about to do anything soon:
But the rapid upstick coud be a mis-read because of the recent bad weather too: 240 kilometer winds been blowing in the caldera
Bad weather never shows up as quakes, so the uptick is real. I give it 6 months, let’s see what happens…
It will be a Big nice eruption of Thoelitic Basalt ash…
The large ammounts of partial melting in Iceland forms lovely thoelites
Is it me or has this year been rather slow when it comes to volcanic activity?
Its probably just me. :/
Don’t worry, 2020 will bring us catastrophic VEI 7+ and laki sized eruptions! Long periods of peace are usually follow by periods of chaos. God and mother nature surely has a funny sense of irony.
Or the lull could continue for a few more decades but the former is clearly the better option.
Swarm at Reykjanes peninsula but looks purely tectonic. No signs of eruption coming.. ☹️
Large earthquake on the Philippines, close to the previous series. M6.8, so damage is likely. Digos City is closest
https://en.vedur.is/earthquakes-and-volcanism/earthquakes/reykjanesridge/
Big earthquake swarm in south Reykjanes now
Whilst roaming YouTube I found this footage from the eruption of Mt. Usu on Hokkaido in 2000.
If I remember it correctly, the 1910 eruption was the first eruption ever where a town was evacuated before the eruption happened on advice of scientists.
The 1944 eruption created a new volcano (Showa Shinzan, which is still smoking a bit nowadays, and was noteworthy because a postman went there everyday to measure the growth of the volcano. I learned this from the volcano museum over there.
The 1977 eruption created a crater on the edge of the town Toyako and lahars eventually destroyed some buildings and apartment complexes. The Japanese decided to preserve the ruins and now the whole area is a museum, with a proper building (excellent) and a signed park along all features.
I overnighted in a cheap ryokan which had cracks in its walls everywhere due to earthquakes. When I learned that Mt Usu had erupted actually at the edge of town I felt a bit less comfortable.
But the locals call it the friendly volcano because it always gives some warning in the form of quakes a few days ahead.
If it keeps a schedule, the next decade could be interesting.
correction: the 1977 eruption should be the 2000 eruption from the video above
That lake there is a caldera. Toya Caldera. It blew up 110K years ago according to the Smithsonian.
Mentioned on BBC TV news that a new sonar survey around Anak Krakatoa has found the sea-bed littered with great blocks of debris from the recent collapse. 70~~90 metres range was quoted.
IMHO, their on-line report is quite good.
https://www.bbc.co.uk/news/science-environment-50798253
Think about it: this is the largest lava lake in the world now!
All the other 4 lava lakes can fit inside Nyiragongos lava lake, with tons of room left..the lake lake is almost 300 meters wide now
🎵The ultrafluid Nephelinite is happly bubbling🌋🎵
Nyiragongos 2016 caldera wall vent thats still going today ( 16 december 2019 ) coud be because pressure in the magma column system is very high.
The lava lake itself overflowed a few days ago looking at latest photos from Nyiragongo posted on social media. Now 16 december 2019 the caldera is rapidly filling.
Higher lava lake levels causes higher pressure in the magma column and on the edifice.. increasing the danger of flank intrusion and draining
New post is up! If you haven’t made your Christmas wish list yet, this may give you some ideas. On the fifth day of Christmas my sweetheart gave to me, one christobalite, two porphyry, three diabase, four alexandrite, five tridymite.. Confused? Do read on!
https://www.volcanocafe.org/mineralisation-processes/
What magma is hottest???
Kilauea or Nyiragongo?
Kilauea is formed by very very large ammounts of partial melting from at least 1530 C astenospheric plume head
Forms kilaueas Thoelitic Basalts.
Probaly the hottest plume on Earth Hawaii is.
Nyiragongo is formed by very very small ammounts of partial melting, partial melting that feeds Nyiragongo is perhaps deeper than any other magma on Earth.
Early stage of slow continetal rifting.
Nyiragonto 1977 had extremely hot temperatures I heard from others.
Both are very hot and fluid
But who is the hottest eruption temperature?
Albert whats your opinion????
What volcano haves the most fluid sillica based lava?
Is there a need to change the evacuation plans for Öræfajökull? That needs to be considered according to Thorvaldur Þórðarson, professor of volcanology and mining at the University of Iceland.
In the article below (in Icelandic) he says that the current evacuation plans are based on a jökulhlaup being the first thing to come down the mountain. However, new data about the devastating eruption of 1362, found during an expedition to the mountain in October, suggest that the first thing to strike in 1362 was a massive pyroclastic cloud. If a similar eruption were to happen, people would only have a few minutes to escape. The only thing to do is to clear the area early enough if an eruption is suspected.
Lurkings don’t be there comes to mind…
In the end of the article he says the eruption in Öræfajökull in 1362 is very similar to what happened in 79 when Vesuvius erupted and destroyed Pompeii, except that the eruption in Öræfajökull was larger.
https://www.ruv.is/frett/telur-rett-ad-breyta-rymingaraaetlun-vegna-oraefajokuls
More video from Usu Volcano.
https://www.youtube.com/watch?v=GYTlMqLJ2Gc
Good thing they are wearing hard hats.
Not a big eruption but to me it looks like a very large volcano.
Reminds me of Yellowstone in the winter, with the steam and snow and trees.
Tiny compared to the bigger volcs in the world 😉
But dangerous since its close to inhabited areras
The viscosity measurements for 2008 – 2018 Kilauea lava lake varies in all papers! 😛from just the same to even a bit lower than Nyiragongo, to a bit higher…
This is weird sicence with diffrent opinions that thats diffrent in diffrent USGS papers.
Anything from 10 pas to 100 in most recent Kilauea overlook lava lake. In 20 papers I looked at…
Nyiragongo is about 20 to 60 Pa.s
Halemaumau 10 to 100 Pa.s
Fissure 8 was 80 Pa.s I think.
Etna is around 3500 Pa.s
Viscosity sicence seems to be insanely tricky😂😂😂
But Kilauea and Nyiragongo are defentivly the most fluid sillicate based lavas in the world!
What about Holuhraun and Fimmvorduhals (Lady E)? Do you know the viscosity of their lavas?
Holuhraun viscosity
Holuhraun is the hottest and perhaps most fluid Icelandic eruption we seen so far by cameras…
Holuhraun had a viscosity of about 100 to 150 Pa.s in the vent as paper says, ( thats about as fluid as Hawaii. )
No measurements was done in Baugur vent.
But it was quite very fluid.
Holuhraun was ( very probaly just somewhat thicker than Hawaii ) as Holuhraun lava channel overflows never made any smooth pahoehoe.
I say 250 to maybe 310 Pa.s for holuhraun.
Holuhraun was extremely fluid compared to all recent Iceland lava flows.
Eyfjallajökull – Fimmvörðuháls
That was much more viscous than Holuhraun
As Fimmvörðuháls was around 100 C cooler or more.
Fimmvörðuháls never developed the hawaiian style fountaining of Holuhraun and never formed the fast fluid flows of Holuhraun.
Fimmvörðuháls had a basalt viscosity similar to Etna and Pacaya about 3000 Pa.s or more.
Fimmvörðuháls never formed the violently boiling action of Baugur… instead it was viscous strombolian – Hekla style lava fountains
Holuhraun viscosity
Holuhraun is the hottest and perhaps most fluid Icelandic eruption we seen so far by cameras…
Holuhraun had a viscosity of about 100 to 150 Pa.s in the vent as paper says, ( thats about as fluid as Hawaii. )
No measurements was done in Baugur vent.
But it was quite very fluid.
Holuhraun was ( very probaly just somewhat thicker than Hawaii ) as Holuhraun lava channel overflows never made any smooth pahoehoe.
I say 250 to maybe 310 Pa.s for holuhraun.
Holuhraun was extremely fluid compared to all recent Iceland lava flows.
Eyfjallajökull – Fimmvörðuháls
That was much more viscous than Holuhraun
As Fimmvörðuháls was around 100 C cooler or more.
Fimmvörðuháls never developed the hawaiian style fountaining of Holuhraun and never formed the fast fluid flows of Holuhraun.
Fimmvörðuháls had a basalt viscosity similar to Etna and Pacaya about 2500 to 3500 Pa.s or even more.
Fimmvörðuháls never developed the fast moving boiling action of holuhrauns vent.
Instead Fimmvörðuháls higher viscosity became Hekla – Etna style lava fountains.
Repost if the previous did not appear
Holuhraun was 1185 C and 49% sillica
Directly from Icelands hotspot
It was an extremely fluid eruption
That should form a very mobile fluid, it was also extremely gas rich that lowers viscosity even more.
The lava flow speed in Baugur in Holuhraun vent was amazing. It was extremely fluid
But it was probaly ( somewhat thicker?) than kilaueas extremely smooth liquidity at its summit lava lakes.
Holuhraun contained looots of small micro – crystals and thats what defentivly prevented smooth glassy surfaces.
But in overall Holuhraun was extremely fluid!
But it lacked most the hawaiian shiney- ness in cooled overflows from channels
Thanks for the answer to last question, Jesper!
The thing about Holuhraun’s lava flows was that it *did* have pahoehoe, but with many, many broken up pieces of pahoehoe. In fact, this is what’s known as “rubbly pahoehoe”. Rubbly pahoehoe usually seem to form as a result of fairly fluid lavas being erupted at very high rates. This kind of lava morphology was also erupted extensively from Laki in 1783-84. Extensive evidence of this kind of lava morphology have found in many flood basalts worldwide, including the Deccan Traps and the Columbia River Basalts. BTW, I’ve read in some science papers that the massive basaltic flows from the CRB and Deccan were indeed somewhat less fluid than those from Kilauea – just like Holuhraun’s lava.
In fact, I view the Holuhraun as being a kind of mini-miniature version of the Laki Eruption, which in turn was basically a miniature version of the true flood basalt eruptions. Only thing is that Holuhraun did not start out with highly explosive eruptions of ash like Laki did, probably because the magma source wasn’t quite as deep (remember that it came from Bardarbunga’s magma chamber), and therefore not nearly as much groundwater for the magma to come into contact with.
So fun you enjoyed it👍🌋
Indeed your words are 100% correct too
Eruptive speeds are also important
Fast impressive fluid basalt eruptions like Laki and Holuhraun and Fissure 8 and much larger tends to form huge open very very fast moving fountain feed channels that feeds extensive Aa flows…
Almost the entire Holuhraun, Laki and Leilani lava flow fields are pure channel feed Aa lava.
You never finds lava tubes in flood basalts and faster basalt eruptions.
Pahoehoes are generaly confined to the very slow but very long lived shield eruptions
Like Puu Oo and Trölladyngja.
Pahoehoe enjoys slow eruptive rates
Rubbly pahoehoe forms in small breakouts along the front of an a’a flow:
It is a secondary texture in flows that are predominantly a’a, Laki and Holuhraun being high rate eruptions are mostly sheets of a’a lava but locally other morphologies might show up such as rubbly/spiny pahoehoe along the flow front or pahoehoe in overflows from lava channels.
Fimmvörðuháls was of course much much thicker and cooler than Holuhraun was.
2010 s start was a cold viscous basalt, just as Heimeay 1973 was a cold and viscous basalt
Souch activity forms large cinder – scoria – ash cones and ”un – clean ashy lava fountains” and lots of scoria. Lava channels and flows happens but they are always Aa flows and competely lacks any fast moving channels…
Heimeay had paticulary massive blocky Aa flows.
Etna haves similar cooler basalt activity with Aa flows and strombolian activity and lava fountains thats can be more violent than Holuhraun because of higher gas content and higher viscosity that fight the gas.
Fimmvörðuháls was as much as 100 C cooler than Holuhraun and that made the diffrence is viscosity..
Fimmvörðuháls never came from Icelands hotspot either.
Holuhraun and Kilaueas Fissure 8 where similar avarge eruptive rates… both fast open channel feed Aa eruptions
Fissure 8 made extremely smooth shiney fluid channel overflows from its fast channels…
Holuhraun made relatively rough Aa like pahoehoe overflows from its fast moving channels near the vent… or pahoehoe spillovers
But lacking fissures 8 smoothness
Both where very smooth and fluid in the fast moving channels, .. but the overflows where very diffrent for Holuhraun and Leilani Fissure 8.
Holuhraun had somewhat higher viscosity
An interesting article on the 3D structure of Piton de la Fournaise:
https://www.nytimes.com/2019/12/18/science/volcano-3d-reunion-island.html
A bit generalizing, but then it is meant for the general public…
Where *is* Nyiragongo getting its weird, alkaline brew ?
I could sorta understand if ‘plume’ was mobilising evaporites such as forming in the Afar Triangle / Danakil Depression, but even that doesn’t seem to fit…
Indeed Nyiragongo is super – strange
Among ”normal sillicate lavas” Nyiragongo is the strangest. Nyiragongos Nephelinite magmas.
Extremely sillica poor 35% Nyiragongo is!
Hawaii is 50% sillica for comparison.
Nyiragongo is rich in alkali minerals and sodium rich minerals and iron rich sillicate minerals.
Nyiragongo is result of very small ammounts of partial melting very deep down in the Albertine Rift. The mantle melting occurs deep down and is of smallest ammounts of the mantle minerals.
Partial melting deep under Nyiragongo is much much smaller in ammounts than under Iceland and Hawaii..
And Nyamuragira, which is just 10 km away, has a strinkingly different composition, basanite, a much more frequent magma that is more silica rich and less alkaline. There is though another volcano in Virunga, Visoke, that has a similar magma chemistry to that of Nyiragongo.
Thats very true…
But even Basanite is rare and very alkaline and sillica poor compared to normal basalts.
Basanite occurs over weak ocean hotspots like Azores and continetal rifts where partial melting is very small.
Intraplate continetal volcanic fields its also occurs
And dying older hawaiian Islands..
Oahu haves both Basanite and Nephelinite.
Nyiragongo and Nyiramuragira area is just
20 000 years old! Thats very productive for being so extremely alkaline and sourced from souch small ammounts of partial melting…
Nyiragongo and specialy Nyiramuragira are very very productive for having souch magmas…
“Before that, Lake Tanganyika, or separate sub-basins in what is now the lake, may have had no outlet other than evaporation.”
Wiki, YMMV, reminded me thus. So, possibly, during initial rifting, some soda lakes developed, now recycled as ‘flux’…
If so, IMHO, it would account for local variations, and make it close kin to the natrocarbonatite lavas of Ol Doinyo Lengai in Eastern Rift…
Nyiragongos Nephelinite is NOT a carbonate – magmatic limestone soda like Lengai.
Nyiragongo is a sillicate magma
But very very low in sillicon and rich in alkali minerals and iron oxides but lots of alkali rich minerals
Sorry, i meant ‘kin’ as ‘mobilised by flux’, not kin by specific chemistry
We did have a good quake on the south west rift zone close to the summit on Mauna Loa.
2019-12-20 14:48:39 3.2 -1.6
It was very close to an other quake yesterday.
2019-12-19 16:39:08 2.9 -1
Mac
Boeing is not doing well. Can’t fly planes, and now it can’t get its rocket into orbit. The report states ‘The primary issue appears to be one of software rather than hardware.’ There does seem to be a pattern here,
Hubris for calling their wee coracle a ‘Star Liner’ ??
They seem to have forgotten about ‘defensive coding’. As with ‘self-driving’ cars that get trapped in retry loops by novelty, rather than braking and sounding horn…
Been a while, before obligatory seat-belts, but I nearly put my driving examiner through screen during test. It was a totally miserable, dark, raining-sideways winter day when I slammed on. “WHATYOUDOTHATFOR ??” I pointed to a barely visible guy in a long black coat crossing road mere yards ahead. “Oh. Didn’t see him, doesn’t count. Drive on–Stop !!”
And, that’s a ‘Pass’. None of the other dozen candidates that morning had ‘sufficient regard to road conditions’…
I remember some 20 years ago Boeing getting flak for moving its manufacturing to a different state that had more relaxed labor laws, and other outsourcing/cost-saving maneuvers. I wonder if that eventually bit them in the “you get what you pay for”.
Yesterday’s press conference had a bit of hand waving as well and seemed to raise more questions than answers. Another one later today.
All we’ve really been told so far as that there was a “Mission Elapsed Time” anomaly and then comms problems which meant the spacecraft did not receive commands (or did not act upon them) from the ground for several minutes at the critical time. They mentioned TDRS handover but the time period with no comms seems to long for that and they said they continued to look into it.
Must have been a nervous time for Boeing as the few times we got a glimpse of the screens at mission control you could see downlink telemetry in lock and the RCS thrusters all firing constantly but no actual insertion burn. Commands were immediately transmitted to start the burn but to no effect,
I’m wondering if they were received but something related to the clock fault prevented them being actioned. Did they transmit a lower level hardware reset in the blind after several minutes to regain comms?
Let me make a complete guess. The various stages have to be done on time and in strict sequence. So there are two ways to initiate the next step, by clock or by sequence. I guess the two got out of sync and the clock started a procedure at the wrong time. Cross-checks were missing or skipped in the software. To me, there does seem to be a similarity with their plane problems, with the software assuming that data is always right. They will find out very quickly why the clock was wrong, but it may take longer to investigate why this caused mission failure and how many other such oversights there are in the software. And the fact that the system ignored the override commands from the ground could be indicative of another software error. Quite a few questions were raised. They may not be quite ready yet for manned flights. Wait and see. Musk now has another chance to gatecrash the manned space program.
Well like “solving” MCAS they can just take input from a second clock and then when they disagree a “CLKFUBAR” warning light could come on then the crew would simply grab the handle between the seats and wind up the backup mechanical “manual time trim” clock.**
** Disclaimer: May not move in all flight conditions
Seems it was not just Boeing with issues yesterday.
https://twitter.com/ulalaunch/status/1208458919351160834
Press conference starting now.
Still some mystery about the comms issues – they said with the spacecraft not being where it thought it was and firing RCS beyond red lines, it took far longer than expected (even under these conditions) to establish a full TDRS link. Still some possible ambiguity about whether it eventually autonomously stabilized the link or they got some command through to help it. Clearly they were running out of time, fuel and red-lines when something brought the TDRS link up and they recovered control.
As for the clock issue they say they simply read the wrong location (or “coefficient”) for the time data from the Atlas V. No they didn’t know how they managed that either…
Though Correlation doesn’t imply Causation, they’ve just announced a board re-shuffle– “With Immediate Effect.”
But, until they restore a strong engineering presence to that level of manglement, they’re re-arranging deck-chairs on the Titanic, uh, ‘Starliner’…
Scott Manley on the Boeing FUBAR.:
And you can clearly see live telemetry at NASA Mission Control on the big screen exactly when they say they had no TDRSS comms. Ground based tracking (or a one way satellite relay) could have been providing that I suppose and that would have been another option to get a signal to it I presume.
There’s quite a swarm ongoing at Greip. Some of the checked quakes (although small) seem to be more shallow than usual for that location. Is the intrusion causing movement of the Holuhraun dyke, or is the intrusion actually starting to breach into the dyke? Probably not likely, but it would be interesting. I don’t have access to my plot tools during Christmas, so I can’t check for myself.
Quite some action at Greip today after some weeks of rest.
Best seen on the Dyngjuháls drumplot, but also the Askja station is registering the quakes.
Aksja is a finetuned station I guess, some other stations nearby do show hardly a signal at the same time.
Heads up !!
http://written-in-stone-seen-through-my-lens.blogspot.com/
Wednesday, December 18, 2019
The Geologic Evolution of Iceland: Part III
– An Excursion from the East Fjords Region through the Northeast Highlands
“The sun knew not where she had housing;
The moon knew not what Might he had;
The stars knew not where stood their places.
Thus was it ere the earth was fashioned.”
Verse from Prose Edda written by Law Speaker and poet Snorri Sturluson, c.1200
==
There are convenient links to parts I & II…
🙂
Great read with much to learn! Thanks!!
Some movement again next to Pu’u’o’o.
At POO, the green component of the tilt which looks, roughly, towards the area northeast Pu’u’o’o that got the intrusion in September-October again shows a similar tilting though more subtle. It looks reversed in the graph meaning that inflation will show as a decrease and deflation as an increase due to the green line, 42º, looking towards the deformation source instead of away from it. Deformation is slower this time so it is still hard to tell in the GPS but it looks like it is starting to show up at some stations like NPOC as an increased west and up drifting so it looks like magma is slowly accumulating in that area. It is interesting that the summit deflation-inflation events show perfectly in the blue line (which is the radial tilt away from Pu’u’o’o) but do not show at all in the green one, not sure why.
Keep an eye open on Iceland, 20°W, just west of Hekla. This is an area where it is likely that the next big SISZ quake might happen. Almost a star there today, could be a foreshock.
Hopefully it is causes a flood basalt and ends the human race.
I am glad you can join in in the Christmas spirit!
Extinction is the best gift at least to me. (As long as it not through any global warming)
You do realize that Homo Sapiens is already extinct? That species was supplanted by the extant Homo Stultus.
http://www.spacedaily.com/m/reports/Unique_form_of_quartz_may_power_deep-Earth_water_cycle_999.html
Interesting PNAS paper. How does it go with our understamding of decompression melt and water in rising magmas?
A new swarm northwest of Mauna Loa
https://pdfs.semanticscholar.org/7258/1f1ce9d941eca9cc6a22b36392feda8d3abd.pdf
Good article / read on Nyiragongos viscosity
Viscosity of lava is measured in Pa.s
Kilauea can be as fluid as 10 Pa.s in some cases.
Halemaumau displayed 30 to 100 Pa.s in many other papers.
In this study… Nyiramuragira and Nyiragongo rocks where crushed and melted in furnaces. And the viscosity measured over a range of temperatures.
These two volcanoes are famous for extremely low viscosity: In this study the results show thats its mostly true: BUT the viscosity for Nyiragongo is not much lower at all than Kilaueas summit.
Nyiragongo lavas viscosity at erupted temperate ranged from below 30 to well much over 100 Pa.s.
This study suggest that Hawaii and Congo haves similar viscosities ( Nyiragongo gets its speed very much due to its very steep slopes )
Nyiragongo and Nyiramuragira are
Nephelinite and Basanite Magmas
and not a basalt at all …
So the title of this article is kind of wrong.
But otherwise is an extremely intresting read
Albert maybe this viscosity study, is intresting for you?
Nyiragongo is very fluid: but its ”insane fludity” is clearly a myth ..
its steep slopes is the main reasons it goes so fast .. its about as fluid as hawaii is in viscosity
It is interesting, but do remember that the slope of a volcano is itself determined by the viscosity. Low viscosity lava builds a broad shield with a shallow slope. Perhaps Nyiragongo has changed its magma recently.
Nyiragongo is largely made up of ash from phreatomagmatic eruptions, small explosions with ejecta landing close to the vent is what probably has given Nyiragongo its conical shape.
Nyiragongos Nephelinites are among the rarest of sillicate magmas
Only a very small ammount of partial melting can produce them.
Nephelinites occur over very weak oceanic hotspots, or as last dying postshield volcanism of Hawaiis strong plume ( Oahu )
But mostly Nephelinite seems to occur in very slow spreading continetal rifts, like Africa and Rhine rift in Germany
The composition is important, but so is the eruption rate. As the crater has a large lava lake, when it drains the eruption rates could be very high. This makes the lava flow faster and further.
https://www.frontiersin.org/articles/10.3389/feart.2018.00121/full
The old dying hawaiian islands, produce the most rare and intresting magmas. As they are dragged away from the Hotspot, partial melting lowers alot.
Oahu and Kauai produce Nephelinite as the very last very alkaline magmatic dregs before going exctinct….
Kauai Late stage volcanism are Nephelinites ( Nyiragongo compsitions )
Mōkōlea Point Lavas in Kauai are Nyiragongo Nephelinites …
Produced by extremely small ammounts of partial melting and are rich is feltspathoids and sodium and alkali minerals.
Go to Kauai Island to grab some Nephelinite! : )
Yes, nephelinite is erupted during the rejuvenation volcanism, this happens in a broad field of monogenetic volcanism along the hawaiian arch, the crust bulges at a certain distance from the big volcanoes of Maui and the Big Island producing decompression melt, this is referred to as the hawaiian arch, it intersects the island chain at Oahu where most of the recent subaerial rejuvenation volcanism has taken place.
DustDevil
I knows that Nephelinite haves much much much much lower sillica content than main shield Kilauea Thoelitic Basalts
But really its not much diffrence in fludity right?
( kilaueas summit lakes are insanely fluid ) just as Nyiragongo is very fluid.
The papers suggest similar viscosity.
But the Nephelinites in Oahu probaly had higher viscosity than main shield Thoelite Basalts as it where much cooler ( Sugarloaf Flow Nephelinite in Oahu was crystal rich viscous. )
But the MōkōLea point Kauai Nephelinites seems to be very low in viscosity ( hot and probaly ascended fast from deep source )
I don’t know much about lava rheology so I don’t can’t say which one has the highest fluidity. Temperature messes significantly with the viscosity so it will be a factor to consider. The distance to the vents also matters, in low rate eruptions the lava forms tubes and insulates itself very effectively, but in a high rate eruption the lava advances as a sheet and therefore cools with distance, the lowest viscosities are found near the vents, this applies also to Nyiragongo, the glass flash flood happened near the fissures at Shaheru where a rare combination of very low viscosity, high rates (which as Albert pointed out makes flows advance faster), steep slopes and proximity to the vents was met.
Can lava flows in Hawaii be as runny? probably. Hawaii (same as Virunga) spans a very broad range in viscosities, the trachytes of Hualalai and Kohala and the lava of Halema’uma’u are a world appart of course. Lava erupted at the ERZ of Kilauea first has to first make it though the extensive storage of this rift zone it cools, differentiates and mixes with old stuff from who knows when so that it is not going to be as fluid as the melt at the summit. On the other hand eruptions in the southwest rift usually feed directly from the summit, here in the 1823 eruption the front of the lava flow is estimated to have advanced at 15 m/s surmounting obstacles such as old cones and this happened over slopes that were shallower than Nyiragongo’s, had this flow been put on the slopes of Nyiragongo I guess it could have been as destructive or even worse.
Nephelinite s are products of very small ammounts of partial melting
Much much much smaller than Normal Basalt
So many Nephelinites are much cooler than basalts. The Oahu Sugarloaf flow was a crystal rich sludge when it was erupted.
https://www.sciencedirect.com/science/article/pii/S0016703716300217
Nyiragongo is very very fluid: but its supprisingly dull and dark dark dark red fountains in directly sunlight.
I read many papers that suggest Nyiragongos lake is below 1000 C
But that cannot be true..?
Patrick Marcel measured Nyiragongos lava lake temperature in 2017 and he recorded well over 1200 C ( he recorded 1280 C ) for Nyiragongo.
But in direct sunlight its lava lake spatter is rather very dark red…
why if its so hot?
Nyiragongo is a very rare sillicate magma and very very sillica poor and mineralogy is unusual…
https://m.youtube.com/watch?v=htY8nVrT57o
https://m.youtube.com/watch?v=gIUTjaefr2s
Just wow these videos of Nyiragongo the lava is amazingly fluid!
This is taken in almost direct sunlight and yea its pretty orange the bubbling so temperature is probaly similar to hawaii.
Temperature measurements of Nyiragongo have only been done a few times… and direct measurements I think only by Tazieff and Marcel
Deep tremor in the Pahala area. The only one this month, they are very sparse lately, but as usual they can come in clusters so more may happen in the upcoming days.
Two “tremor quakes” located by HVO:
2019-12-29 10:01:53 UTC M2.1 36.2 km deep
2019-12-29 10:00:20 UTC M2 39.1 km deep
The tremor followed on from a new swarm northwest of Mauna Loa (see above). Which is funny since the tremor is related to Pahala. Coincidence? Stress transfer?
Probably coincidence I would say.
Meanwhile at Kilauea
Tilt
And inflation
Pu’u’o’o and the area northeast of it have also stopped inflating, looks as if supply has halted.
Just wondering. Should we try to keep obviously current volcano talk on the main current post thread as used to happen? The bar is a brilliant idea but I do wonder if casual visitors are missing interesting volcano chat because they don’t check out the bar.
Or is the balance right just now?
Good question. I was just wondering where to put the link to a new web cam looking down into the crater of Agung that was installed on December 28. I decided to go here, but I guess no one would complain if I had gone for the main thread.
You can reach the webcam from this link:
https://magma.esdm.go.id/v1/gunung-api/cctv/AGU
Thanks for very nice link with cams on several hot volcanos.
I am also checking up on Agung now and then.
.
Maybe this camera, after the next eruption, will keep people from climbing the mountain?
I would have no objection to these volcano questions to be discussed on the main blog.
Can some one please help me find more information about Sotara? Magma is actively flowing it’s conduits and no one at SGC seems to care!
This seems to be their main site but you know that already… https://www2.sgc.gov.co/ProgramasDeInvestigacion/geoamenazas/Paginas/OVS-Popayan.aspx
The QMS sites tab links to the volcanoes.
Publishing-wise, the last decent paper seems to be this, published 2017: https://www.sciencedirect.com/science/article/abs/pii/S0377027317303098
( PDF: https://www.researchgate.net/profile/Jorge_Alpala_Aguilar/publication/317049927_Monitoring_remote_volcanoes_The_2010-2012_unrest_at_Sotara_volcano_Colombia/links/59fa2de7458515d20c7cbc10/Monitoring-remote-volcanoes-The-2010-2012-unrest-at-Sotara-volcano-Colombia.pdf )
The cause of the mass death of starlings in Wales a few weeks ago has been found. The birds were found dead on the road. Poison had been suspected. But it now turns out that it was caused by the asphalt road being wet after the heavy rains. Starlings fly in flocks which make sudden movements (for instance see https://www.youtube.com/watch?v=V4f_1_r80RY). The wet road reflected the sky and it wasn’t recognized as a solid surface by the birds. They all flew into it at high speed and died of trauma.
It made me wonder how a driverless car would respond to a tilted mirror?
Kamikaze birds …
Impromptu accretionary prism…
Incident, but not the cause, is referenced in current ‘Fortean Times’. Apparently the locals remember several prior incidents, all associated with standing water on that stretch of road.
Hurricanes and Maya. They overlooked volcanoes, though.
https://arstechnica.com/science/2019/12/hurricanes-climate-change-and-the-decline-of-the-maya/
Betelgeuse still dimming
Sadly probably not yet about to blow up.
http://www.astronomerstelegram.org/?read=13365
Astronomy Picture of the Day
2020 January 1
Betelgeuse Imagined
Illustration Credit: ESO, L. Calcada
https://apod.nasa.gov/apod/ap200101.html
And for those of us without a neutrino detector in the basement (that’s probably us all I’d imagine – apart from maybe Albert 🙂 ) you can sign up to SNEWS: SuperNova Early Warning System
https://snews.bnl.gov/
Impress your friends by getting an email alert in the pub that neutrino count indicates we’re all about to die in a Gamma Ray Burst – although fortunately that’s not likely to happen with Betelgeuse 🙂
No worries. It is big but bigger stars are known. We once found one that would have extended to the orbit of Saturn. It has faded and I think is now fainter than it has been over the past century. That is unusual: it is variable but not by this much. Looking at historical data, I have the impression that it has faded equally at blue and yellow but not (or not much) in the ultraviolet. If correct, that is typical for stars that become cool enough to allow some oxides to form in their atmosphere, specifically VO and TiO. Those molecules absorb optical light but not ultraviolet. It tends to happen between spectral types M2 and M6, and Betelgeuse is M2. So my guess is that that is all it is. We don’t know the mass all that well and it is not fully certain that it is massive enough to go supernova.
It used to be the star with the largest angular (apparent) diameter in the night sky. No longer: I was involved with finding the current record holder.
https://phys.org/news/2016-12-famous-red-star-betelgeuse-faster.html
A bit dated, but suggests was binary until ~100 Kyr BP when ‘The Big B’ engulfed partner…
Must wonder if that Alpha Ori B may still be ‘sorta intact’ within the ‘vog’, and if its orbit is ~ 5.9 years…
😉
Might have eaten a companion, although the numbers in that press release don’t quite make sense. Stars do swallow close companions when they become red giants, mainly hot Jupiter type planets. But I don’t see much evidence of that in Betelgeuse.
Ahh, Albert in the Stars! Sorry i’ve been a little busy lately…. record heat then ice storms turning to snow storms and then below zero cold… and my car door froze shut. nuts it’s always something… Anyway, i’ve missed the bar and need to catch up.. so there’s no real danger if Betelgeuse goes nova… is there?? or should i make sure to get to confession this week (i hear You snickering, Carl, stop it) my hubby gets anxious about stuff he reads on the internet… and i keep telling him… the only thing he has to fear is …………………….me. 😉
and You were involved with finding the current record holder… that must have been interesting!… anyway it would help me out if i could prepare Hubby if there will be something unusual to see with Bjuice. Thanks, And Best!for the New Year!… motsfo.
No danger from Betelgeuse. We do not know if it will go supernova. If it does, it will be sometime in the next few million years, so the chance that it will be this century is of the order of 0.01%. For comparison, that is 10-100 times less than the chance of a VEI-8 eruption this century (in case Hubby really want so to worry about something..) The current fading is very unlikely to have anything to do with what goes on in the centre of the star. And if it does blow, all that will happen is that we have bright nights for a month or two, after which the sky is missing one star.
The record holder is a star you have never heard of, called R Dor. Only visible from the southern hemisphere.
Thanks, Albert, and with my luck, it will happen in the summer when all the nights are bright up here and i’ll miss it entirely! i’ll let my husband know. Thought patterns change with Parkingson’s. It’s been interesting. Tonight he asked what would he do if i died…. told him to call for help and gave him a list… picking through old age can be an adventure for sure. 😉