Alleged to achieve Kp 5 at 21:00 UTC. On March 04.

Didn’t see a thread yet for this.

It is supposed to begin building from around 12:00 UTC until maximum attained later in day.

Would welcome @Jesterface23 opinions here. 😊

Any indication as to what the cause is? Pleasant surprise if we manage it 😀

4 minutes ago, BlueRoom said:

Any indication as to what the cause is? Pleasant surprise if we manage it 😀

Was it not the SE filament liftoff?

5 minutes ago, BlueRoom said:

Any indication as to what the cause is? Pleasant surprise if we manage it 😀

This is from a filament eruption form SE quadrant. As much as it is being described as earth directed, looking on Enlil, it appears it may just graze us on the 4th, with the majority of it is going south of Earth 😊 I will be watching closely from the UK

1 hour ago, MJOdorczuk said:

Was it not the SE filament liftoff?

Yes.

If our east coast gets some clear weather it might turn out ok. And persists until dark for us west coast and central too.

While we wait for a possible CME, you can read an interesting site where you can learn a lot of interesting things. Liked the simple presentation of the materials. e.g,

https://www.frontiersin.org/research-topics/17314/the-magnetic-structures-and-their-role-in-the-evolution-of-coronal-mass-ejections/articles

Uses some interesting terms:

ICME – Interplanetary Coronal Mass Ejections

I-ICME - Isolated ICME

M-ICME - multiple ICMEs

S-ICME - shock-ICME interaction events

Bs - southward component of the magnetic field

another interesting article on how CME evolves into ICME, what happens to it as it flies towards the ground:

https://link.springer.com/article/10.1007/s11214-017-0394-0

I guess we'll find out, but I'm not too certain we will be able to see a shock arrival from this CME.

3 minutes ago, Jesterface23 said:

I guess we'll find out, but I'm not too certain we will be able to see a shock arrival from this CME.

Same, it seemed to be directed too far south

8 hours ago, Samrau said:

While we wait for a possible CME, you can read an interesting site where you can learn a lot of interesting things. Liked the simple presentation of the materials. e.g,

https://www.frontiersin.org/research-topics/17314/the-magnetic-structures-and-their-role-in-the-evolution-of-coronal-mass-ejections/articles

Uses some interesting terms:

ICME – Interplanetary Coronal Mass Ejections

I-ICME - Isolated ICME

M-ICME - multiple ICMEs

S-ICME - shock-ICME interaction events

Bs - southward component of the magnetic field

another interesting article on how CME evolves into ICME, what happens to it as it flies towards the ground:

https://link.springer.com/article/10.1007/s11214-017-0394-0

Wow. Incredibly comprehensive. Has almost as many research credits as it does text body. 🤣🤣

Some data from SolO so far, which was hit by this CME around 03-03T14Z:

Just now, Philalethes said:

Some data from SolO so far, which was hit by this CME around 03-03T14Z:

When would that hit us?

15 minutes ago, stargazer007 said:

When would that hit us?

Assuming a speed of 425 km/s and just taking that over the additional 0.4 au to us, then it'd hit 03-05T06Z, which is in a little less than 27 hours, but that's obviously to be taken with some big grains of salt.

EDIT:

Rechecking the math on this I'm not sure what went wrong, but as per that speed it would have reached at around 02:30Z, not 06Z, on 03-05. Speed seems to have quickly dropped down to 400 km/s though, so more likely estimate based on that would have been around 04-05Z (which has already passed, seemingly with no arrival).

Edited March 5Mar 5 by Philalethes
bad math

Solar Orbiter is about ~13 degrees closer to the CME. It will be interesting to see if it can reach us.

53 minutes ago, Philalethes said:

Assuming a speed of 425 km/s and just taking that over the additional 0.4 au to us, then it'd hit 03-05T06Z, which is in a little less than 27 hours, but that's obviously to be taken with some big grains of salt.

@Philalethes Where did you get that speed? When I eyeball ENLIL at impact at Earth, it is closer to 480 km/s.

If SOIO is 0.6AU from the sun (per your info), a back of the envelope calculation shows the speed 472 km/s = 150x10^6 km * 0.6AU / (2.2 days * 24 * 3600).

Edited March 4Mar 4 by JessicaF

1 hour ago, JessicaF said:

@Philalethes Where did you get that speed? When I eyeball ENLIL at impact at Earth, it is closer to 480 km/s.

If SOIO is 0.6AU from the sun (per your info), a back of the envelope calculation shows the speed 472 km/s = 150x10^6 km * 0.6AU / (2.2 days * 24 * 3600).

From the low-latency quicklook data I posted an image of above; you can see the measured speed near the top, and how it changes at the time of impact (the red line, V_x). You can find it here, under the "Low Latency" tab.

As for your calculation, it's correct for the values you state, but not sure where you're getting 2.2 days from. Impact was closer to 11:30Z, so that would make it roughly 1 day and 17 hours, or 41 hours to keep to a single unit of time. That's a bit more than ~600 km/s on average over those 0.6 au. Enlil predicted impact roughly 4 hours earlier.

As for why the average speed was 600 km/s and the measured speed is ~400-450 km/s, it's because CMEs slow down quite a lot as they travel, especially in the beginning.

From LASCO observations, the average CME acceleration for different CME velocity ranges was determined (Yashiro et al., 2004):

- for slow CMEs (V <= 250 km/s) the average acceleration a = 6 m/s2;

- CMEs with velocities close to the solar wind speed (250 km/s < V <= 450 km/s) have a small acceleration a = 1.6 m/s2;

- CMEs with velocities greater than the solar wind speed (450 km/s < V <= 900 km/s) decelerate with acceleration a = - 4 m/s2;

- fast CMEs (V > 900 km/s) decelerate with a = - 16 m/s2

https://www.researchgate.net/publication/309477965_Koronalnye_vybrosy_massy_in_russian

Edited March 4Mar 4 by Samrau
fixed errors in auto-translation

Hopefully it gives a decent impact and is not a total miss Its supposed to arrive later today.

if we had a shock arrival from this which could happen but not entirely likely that would be good.

arrival around 22:00 March 4th. which is about 7 hours from now.

5 minutes ago, oaooaiia9i98 said:

Hopefully it gives a decent impact and is not a total miss Its supposed to arrive later today.

let's hope so. EPAM shows a slight increase in protons. usually, with moderate and higher CME influence, the protons value rises to 1.0E+06

Almost to around 3 days of travel at this point, the maximum arrival velocities at that time may be around 475km/s. Maybe bumped up a little to 500km/s if traveling in the solar wind without getting ripped apart.

Edited March 4Mar 4 by Jesterface23

It's rather slow and the magnetic field at Solar Orbiter was at about 25 nT. Sounds rather weak, I would say. I'm rather skeptical about the prospects of Kp5 :/

47 minutes ago, Jesterface23 said:

Almost to around 3 days of travel at this point, the maximum arrival velocities at that time may be around 475km/s. Maybe bumped up a little to 500km/s if traveling in the solar wind without getting ripped apart.

Wouldn't that be unlikely given how SolO is in a better position and only measured velocities around 400-450 km/s as it passed?

42 minutes ago, MJOdorczuk said:

It's rather slow and the magnetic field at Solar Orbiter was at about 25 nT. Sounds rather weak, I would say. I'm rather skeptical about the prospects of Kp5 :/

I'm not too hopeful myself, but I guess it's all we have at the moment, heh. At least the B_N measured at SolO was decent, but there's of course no guarantee that that will be the same when it hits us.

12 minutes ago, Philalethes said:

Wouldn't that be unlikely given how SolO is in a better position and only measured velocities around 400-450 km/s as it passed?

I'd guess it is out of the CH HSS at this point while we are still in it. With the solar wind velocities staying at around 500km/s at L1 though, it sure isn't going to help with any noticeable impact.

17 minutes ago, Jesterface23 said:

I'd guess it is out of the CH HSS at this point while we are still in it.

Yeah, from the plot it certainly looks like the Vx had been stable at around 400 km/s for at least 24 hours or so before the jump up to 425-450 km/s on impact. Seems to quickly have gone back down to ~400 km/s where it's stayed since then.

Glendale (for what it's worth) @ 19.53 GMT INTERPLANETARY SHOCK (?) detected that will hit Earth at ~19:53 GMT with an IMF strength of 8 nT.

Edited March 4Mar 4 by BlueRoom
.

alright so far if this even is the CME BZ is fluctuateing a bit.

with an IMF strength of 8 nT.

hopefully its a bit better then that.

maybe its arriveing 3 hours earlier then expected.

Edited March 4Mar 4 by oaooaiia9i98