How do you identify a delta using GONG? It's considerably more difficult now without SDO

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

In science as in engineering there is no such thing as a silly or pathetic question. The only stupid question is the question not asked. Even the great Galileo hit a wall with his knowledge only to use god as a conclusion. It then took masses of great people who stood on his shoulders to further the advancement of his studies and progress to the field of answers we have today. 

I think he also paid dearly for that assertion.  I will add my humble observation that when we attempt to draw conclusions scientific investigation typically stalls or stops completely.  It’s still a lot of fun trying to figure stuff out and I hope native curiosity is never stifled. 

are there any substorm map trackers?
for example here was the may 10-11 event, there were satellite photos released such as this


I'm wondering if theres any live camera like this

6 minutes ago, yahya said:

I'm wondering if theres any live camera like this

No live footage. Mostly it’s a mosaic image taken from several passes of a satellite. There isn’t a main science instrument for live oval mapping 

1 hour ago, yahya said:

are there any substorm map trackers?
for example here was the may 10-11 event, there were satellite photos released such as this


I'm wondering if theres any live camera like this

A bit off-topic @yahya but if you ever have an opportunity to fly north during geomagnetic activity in the states and it’s relatively clear, you may be as fortunate as I was in 1980 I think it was.  Nearly the entire oval was viewable from the cockpit of the 737 we were in.  Was unforgettable. Nowadays you probably aren’t allowed in the jump seat as they call it, but even the facing windows were awesome!! 

I have a question about the importance of the speed of the solar wind at the time when the aurora starts. At low/medium speed, does it take more time for the aurora to appear, even though the IMF parameters are very good?

3 minutes ago, Arek Byrtek said:

I have a question about the importance of the speed of the solar wind at the time when the aurora starts. At low/medium speed, does it take more time for the aurora to appear, even though the IMF parameters are very good?

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).

is it possible we've entered a ch hss

I have another question: what does "Transequatorial coronal hole detected" mean and how will it impact us?

 

On second thought, I suppose it's obvious what it means - haha, so I guess I just would like to know how it impacts us

Edited January 2Jan 2 by Stella

1 hour ago, Stella said:

I have another question: what does "Transequatorial coronal hole detected" mean and how will it impact us?

 

On second thought, I suppose it's obvious what it means - haha, so I guess I just would like to know how it impacts us

if i'm right "transequatorial" means it's probably pointing near the equator or something

5 hours ago, Stella said:

I have another question: what does "Transequatorial coronal hole detected" mean and how will it impact us?

 

On second thought, I suppose it's obvious what it means - haha, so I guess I just would like to know how it impacts us

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.

10 hours ago, MJOdorczuk said:

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 this is quite right in light of more contemporary understanding. See e.g. this paper:

Quote

This led to the much-used “epsilon factor” coupling function, ε (Perreault & Akasofu, 1978). Unfortunately, there was an error in the theoretical basis for ε (Lockwood, 2019) which causes it to perform significantly less well, on all timescales, than other coupling functions (Finch & Lockwood, 2007). A large number of alternative formulations have been proposed since (see reviews by Newell et al. [2007], McPherron, et al. [2015], and Lockwood and McWilliams [2021b]).

I did in fact briefly mention the Newell coupling function in a post not too long ago; there v is scaled to the power of 4/3, a power law rather than a linear dependence, whereas Bt is scaled by 2/3. This is also a bit more in line with how dynamic pressure is proportional to the square of the velocity (and only linear with density, although density and magnetic field strength aren't the same thing).

are random density and speed spikes normal in a coronal hole

Why does Venus not have the same magnetic field around it as Earth. And since it has almost no magnetic field, how is its atmosphere held in place. Especially since there is stronger solar wind there, not to mention it has slightly less mass than Earth. Yet it has an atmosphere a lot thicker than Earth's. How? And why is its composition so totally different from ours? Where did all the CO2 come from? And why is there no water in the atmosphere or on the planet? For that matter, why is Earth the only planet with oceans? Shouldn't H2O be evenly distributed across the Solar System?

I know it's a mouthful but the questions just keep coming. Thanks for any thoughts.

5 hours ago, 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.

OHHHHHHHHHHHHHHHHH, i get it now

occasionally, the kiruna magnetometer tends to fluctuate a lot and every minute, but why though?

5 hours ago, stargazer007 said:

are random density and speed spikes normal in a coronal hole

The random spikes are not related to coronal holes but are invalid data from the satellite.

1 hour ago, YourLocalCapybara2 said:

occasionally, the kiruna magnetometer tends to fluctuate a lot and every minute, but why though?

That’s normal behaviour as we are still influenced by the waning CME

18 hours ago, Gene said:

And why is there no water in the atmosphere or on the planet?

Seems like I remember seeing a documentary where they said there used to be water, but it all evaporated (something caused the change, can't remember what) -- but you can probably find out by visiting wikipedia page about Venus

Is it technically possible for a sunspot to form at or very close to the Sun's poles? If so, has it happened before?

2 hours ago, Scienceboy said:

Is it technically possible for a sunspot to form at or very close to the Sun's poles? If so, has it happened before?

Look at the butterfly diagram which plots the sunspot latitudes over a period of time. There you can see what the highest sunspot region latitude is. As you can see no sunspot regions have formed near the Sun's poles but at max 40 degrees. In the beginning of each cycle we see the highest latitude sunspots and as the solar cycle progresses they get closer and closer to the equator.

Why are the Potsdam Kp values sometimes substantially different from the NOAA Kp values for some geomagnetic storms? For example on October 2, 2013 the Potsdam max Kp is 8- while the NOAA max Kp is only 6. https://www.spaceweatherlive.com/en/archive/2013/10/02/kp.html

I notice on the page I linked the NOAA Kp index is "estimated" and the Potsdam Kp is "official." Does that mean that the Potsdam Kp is the more accurate representation of the true geomagnetic conditions at the time?

1 minute ago, Aten said:

Why are the Potsdam Kp values sometimes substantially different from the NOAA Kp values for some geomagnetic storms? For example on October 2, 2013 the Potsdam max Kp is 8- while the NOAA max Kp is only 6. https://www.spaceweatherlive.com/en/archive/2013/10/02/kp.html

I notice on the page I linked the NOAA Kp index is "estimated" and the Potsdam Kp is "official." Does that mean that the Potsdam Kp is the more accurate representation of the true geomagnetic conditions at the time?

SWPC Kp is based on 3 US magnetometer stations. Potsdam Kp is based on 13 magnetometer stations. So SWPC gives a preliminary Kp as it is based on less stations whereas Potsdam Kp includes 13 magnetometer stations and is thus more accurate for determining the global Kp. 

Here's my stupid question. (I'm actually glad this thread exists because I honestly feel completely confused as to why this is happening). 

The "Aurora Map" or "Aurora Oval." 

On New Years Eve, the maps on every source I use completely froze. Each app, NOAA's website, this website... all of them. Slowly they all came back yesterday. However, looking at each of those maps right now, I am seeing something that doesn't make sense to me. They are all showing the current Aurora Oval Map to be above Iceland/Greenland as of right now. It is currently the middle of the day and broad daylight in this area. Typically, I see the map move to areas that are all in darkness after nightfall. 

Are these maps still broken or is this an anomaly/phenomena that is completely new to me?

 

Thank you in advance!

Jim

19 minutes ago, WindKeeper said:

Here's my stupid question. (I'm actually glad this thread exists because I honestly feel completely confused as to why this is happening). 

The "Aurora Map" or "Aurora Oval." 

On New Years Eve, the maps on every source I use completely froze. Each app, NOAA's website, this website... all of them. Slowly they all came back yesterday. However, looking at each of those maps right now, I am seeing something that doesn't make sense to me. They are all showing the current Aurora Oval Map to be above Iceland/Greenland as of right now. It is currently the middle of the day and broad daylight in this area. Typically, I see the map move to areas that are all in darkness after nightfall. 

Are these maps still broken or is this an anomaly/phenomena that is completely new to me?

Thank you in advance!

Jim

They're still trying to correct them at the moment 

Thank you @Parabolic! I was starting to get considerably confused.