On 1/2/2025 at 9:16 PM, Parabolic said:

It means there's a fairly large coronal hole that spans across both hemispheres. They can be a prolonged source of enhanced solar wind due to their size. The shape is an important aspect because they can create something like a shock front ahead of the initial wind. If the western edge mostly vertical and flat the winds are usually much more abrupt. If it's rounded or pointed like a triangle the winds tend to increase gradually.

Thank you!

are random speed and density spikes normal as earth exits a ch hss?

9 minutes ago, stargazer007 said:

are random speed and density spikes normal as earth exits a ch hss?

Yes it’s just useless data  and happens often 

also please ask questions like this in only one thread, ideally this one since it’s on topic 

ace epam is also going crazy is that just bad data?

2 hours ago, stargazer007 said:

ace epam is also going crazy is that just bad data?

Yes, that would be considered bad data spikes. Unfortunately ACE has a damaged proton monitor so this sometimes occures for a few minutes to several hours.

Regarding SUVI, I know the different exposures (angstroms?) help us see different features on the sun, but I'm just curious what 94 & 284 tell us, or if anyone uses those for something.

1 hour ago, mymorales said:

Regarding SUVI, I know the different exposures (angstroms?) help us see different features on the sun, but I'm just curious what 94 & 284 tell us, or if anyone uses those for something.

94 Å is mostly for viewing details during flares while 284 Å helps identify CME's, or other eruptive events, as they disturb/pass through the outer corona. 

why is it that states of the US such as florida got to observe auroras really low (30 degrees north) but cities such as almaty(43 degrees north) did not, even though it was supposed to be observed that south?

40 minutes ago, YourLocalCapybara2 said:

why is it that states of the US such as florida got to observe auroras really low (30 degrees north) but cities such as almaty(43 degrees north) did not, even though it was supposed to be observed that south?

It can be very complicated during an auroral event.  Even assuming similar light pollution. If you’ve observed time-lapse videos of strong events, things change very rapidly at times.  The magnetic latitudes around the earth also vary widely.  At 47 degrees N. geographically in Seattle for example I would have a much better shot at 47 degrees N in Wisconsin for one instance. The magnetic field lines are definitely being distorted longitudinally too.   That’s a simple answer to a complex problem. 

https://www.swpc.noaa.gov/products/27-day-outlook-107-cm-radio-flux-and-geomagnetic-indices
 

how is it possible to forecast KP 27 days in advance? How accurate is it 

28 minutes ago, yahya said:

https://www.swpc.noaa.gov/products/27-day-outlook-107-cm-radio-flux-and-geomagnetic-indices
 

how is it possible to forecast KP 27 days in advance? How accurate is it 

It's not terribly inaccurate, but definitely should be taken with a heavy grain of salt. It's based on the assumption of reoccuring features still being active after about one full rotation of the sun. For example: large transequatorial coronal holes can survive for several rotations and are a fairly consistent source that produce disturbed geomagnetic conditions.

However they are not typically a contributor to F 10.7 Solar flux index.   This is even harder to predict accurately imo yet USAF typically is within 30 points.  

Here's my stupid question. It's been a hot minute since I've been here; it looks like there is a new satellite for imaging of the sun. Is the older satellite that gave us the color coded polarities (blue and red) still active and producing images? Just for my personally I preferred that method of looking at sun spots 

44 minutes ago, Yani said:

Here's my stupid question. It's been a hot minute since I've been here; it looks like there is a new satellite for imaging of the sun. Is the older satellite that gave us the color coded polarities (blue and red) still active and producing images? Just for my personally I preferred that method of looking at sun spots 

Yes HMI magnetogram is back up and running. If you didnt know it was down from late november to about a week ago iirc so we had to use GONG magnetograms as a replacement. 

42 minutes ago, Yani said:

Here's my stupid question. It's been a hot minute since I've been here; it looks like there is a new satellite for imaging of the sun. Is the older satellite that gave us the color coded polarities (blue and red) still active and producing images? Just for my personally I preferred that method of looking at sun spots 

Around the end of November JSOC's server room at Stanford experienced some flooding, which caused outages in the processing of the data; it's been discussed in this thread. The satellite itself (SDO) was perfectly fine, and still is. In the meanwhile imagery from GONG, which is a network of ground-based telescopes, was used. Now processed images from SDO are available again, and are being shown here on SWL too.

What is this?

I assume from the tail it is something that is off-gassing.

(Which comet is this, anyone know?)

Is it this?

Edited January 16Jan 16 by Nico

24 minuten geleden, Nico zei:

Is it this?

Yep, it's the comet talked about in that topic

is it actually better to go to the arctic during solar minimum than solar maximum? 

as I understand it, flying to the arctic is a gamble, and whether you'll see the lights dancing overhead or you'll have a low activity week is completely chance. But, as far as I'm aware, coronal holes are more common in solar minimum rather than in solar maximum, and produce more green/pink aurora as opposed to the pillar-y aurora that CMEs cause. They also have a longer geoeffective period, so I'm just curious, since I'm going to the arctic now for the fourth and final time for a while, especially since my last two trips have mostly been low activity weeks outside of one or two standout nights (march 2024 & late sep/early oct 2024) if it's actually better to plan for the arctic near minimum and chase nearer to midlatitudes during maximum?

Edited January 26Jan 26 by linkedwinters

3 hours ago, linkedwinters said:

is it actually better to go to the arctic during solar minimum than solar maximum? 

as I understand it, flying to the arctic is a gamble, and whether you'll see the lights dancing overhead or you'll have a low activity week is completely chance. But, as far as I'm aware, coronal holes are more common in solar minimum rather than in solar maximum, and produce more green/pink aurora as opposed to the pillar-y aurora that CMEs cause. They also have a longer geoeffective period, so I'm just curious, since I'm going to the arctic now for the fourth and final time for a while, especially since my last two trips have mostly been low activity weeks outside of one or two standout nights (march 2024 & late sep/early oct 2024) if it's actually better to plan for the arctic near minimum and chase nearer to midlatitudes during maximum?

Probably.  However consider the time of year you are above 60 degrees latitude.  Much Aurora gets washed out during summertime “ white nights”.  It’s also rather unpleasant at -40 f. During winters. Dress appropriately!  Haha. 

With those considerations and the general fact that storms are more likely to be higher in KP values near equinox, if I had a choice, I would time my arrivals around spring and fall. Although higher values may occur at any time, of course.   

Edited January 26Jan 26 by hamateur 1953

it's scheduled right around the march equinox, 18-25. I'm hoping this coronal hole right now maybe lasts a few rotations and also SOMEHOW is geoeffective during our time there, but I have no idea how these things work lol

4 hours ago, linkedwinters said:

it's scheduled right around the march equinox, 18-25. I'm hoping this coronal hole right now maybe lasts a few rotations and also SOMEHOW is geoeffective during our time there, but I have no idea how these things work lol

It’s largely a matter of luck anyway, but you are taking the right steps!  Haha.  CH form and disappear throughout all cycles.   A Kp 5 above 60 degrees latitude would be a nice event to witness.  Hope it works out for you!  

On 12/15/2024 at 8:39 AM, Денис Максименко said:

I don’t know if this is considered a SpaceWeather topic, in theory it is. Who can say anything about what is happening in the USA with UFOs? It has gone so far that even Trump spoke about it and said to shoot down UFOs. Even at the beginning of 2024, the media said that 2025 would be the year we met aliens. What do you think about this, experts - write about it. Also, can the Americans also see or hear something like this?

Drones, lots of drones. Drone research is paramount for military and pursued by every military nation on the planet right now. The last few military fashion shows (military tech conventions) are full of new drones, new automation etc. What you are seeing is a drone.

 

On 12/28/2024 at 10:17 PM, antonyhickin said:

Even the great Galileo hit a wall with his knowledge only to use god as a conclusion.

 

Newton did the same thing, when his formulas could not scale to 3 orbiting bodies. 

On 1/8/2025 at 7:05 PM, stargazer007 said:

are random speed and density spikes normal as earth exits a ch hss?

 

Yes, for example, the Earth has an average speed around the Sun, but this doesn't mean it travels the same speed all the time. Same with the Sun and its weather; averages might show some pattern, but the pattern won't show actual speeds. I don't know if this was what you meant. 

 

On 1/2/2025 at 1:56 AM, MJOdorczuk said:

Solar wind speed has two main effects. One is the fact that we detect the parameters at L1, which is 1.5 million km away from us, so the wind has to physically travel all that distance (then there is Alfven speed propagation, but it is much more dependent on the magnetotail shape and the magnetic field strength). Another thing is how much energy from the solar wind is injected into magnetosphere. As far as I am aware, usually the models are taking energy input proportional to the velocity, thus twice faster speed should result in twice the energy input. Taking Akasofu epsilon as an example, magnetic field magnitude has a square impact, so going up from 500 to 2000 km/s (fourfold) in solar wind is the same as going from 10 to 20 nT (twice).

 

I don't think the energy is directly translational from velocity. Since velocity involves the mass of the objects (protons) the mass will create drag, so the ratio won't be 1:1. Also, plasma operates a bit different than typical wind, and its density/viscosity will have a role to play in the ratio you suggest. 

 

 

On 12/28/2024 at 7:47 PM, linkedwinters said:

The xray flux is at a constant M level! What does that usually mean?

 

The average flux is flares divided over time, which will give the background flux. It's a blurry image of what is going on, but this is what the background flux means as far as I know. Those peaks (flares) will raise the average due to their magnitude. Since each class (A,B,C,M,C, X, etc.) is like the Richter scale, and each numerical increase step is 10x the previous step in terms of energy. 

Edited January 27Jan 27 by Archmonoth

2 hours ago, Archmonoth said:

I don't think the energy is directly translational from velocity. Since velocity involves the mass of the objects (protons) the mass will create drag, so the ratio won't be 1:1. Also, plasma operates a bit different than typical wind, and its density/viscosity will have a role to play in the ratio you suggest. 

I am unsure, how the mass and drag are connected here. Most models (if not all) assume the same, nearly fully proton plasma, so the proton mass is just a scaling factor. Not sure also, where you get viscosity here from. If by the ratio you mean linear relation between the solar wind speed and the energy injection, it varies a bit, and I just based it specifically on a rather old Akasofu's epsilon. Some models take different exponent factor.

On 12/16/2024 at 3:26 PM, Gojira Prime said:

Speaking of Orion, and also only slightly solar related, anyone else desperately hoping Betelgeuse goes supernova in our lifetime so we can experience one of the most incredible sights in the sky? It will apparently outshine the full moon!

In the meantime, not supernova but maybe a recurrent nova in a few months : T CrB in Coronae Borealis could be visible with naked eye (well, not as spectacular as Betelgeuse would be). Could happen around the 27th of March (... or later...) according to a paper I have read. 

That would be impressive.  There was a lot of craziness regarding Betelgeuse a bit ago.  Either would be pretty fun. Especially if viewable in daytime skies like year 1054  Crab Nebula was chronicled  “ The guest star” in Chinese documents 

Edited January 27Jan 27 by hamateur 1953