Ron NL Posted May 31, 2020 Share Posted May 31, 2020 Aimed at Earth ? In this article @ spaceweatherlive.com (from yesterday) https://www.spaceweatherlive.com/en/news/view/409/20200529-first-m-class-solar-flare-of-a-solar-cycle-25-region it says that the eruption (or better the resulting radiation) was "not aimed at Earth" meaning that it passes the earth ..it will not hit earth ...and as a result it will not cause any effects on earth. Questions: 1) So when is something aimed at earth ? ...when it is right in the centre of the sun (as seen from the earth) ? 2) I assume the pics are taken from the direction of the earth (by spacecraft) ... i assume that if it sees something that it sees those things that are visible from the direction of the earth ... in other words everything you see on those sdo pics & vids are the portions that are directed towards earth ...so how can spaceweatherlive.com say "not aimed at earth" ? they probably should say that the strongest part of it is not aimed at earth (ie: some of it will reach earth ...namely that what we see in the pics) I find it confusing ... probably because spaceweatherlive only counts absolute max radiations as valid radiation ...which is not the reality ? Link to comment Share on other sites More sharing options...
Vancanneyt Sander Posted May 31, 2020 Share Posted May 31, 2020 The source of the solar flares was behind the solar limb, only the magnetic loops from the region where visible resulting in a recorded elevated x-ray measurement with a M1.1 solar flare. The solar flare only caused a minor R1 radio blackout, no elevated solar protons or electrons. Because for the impulsive nature of the flare and because it was behind the limb, the flare will have no impact geomagnetically (no CME and due to the location even if there was one it wouldn't be aimed at Earth). Please read our help section about CME and their effectiveness, also learn a bit about the Parker spiral that is also at play with determining the geoeffectiveness of a CME. 2 Link to comment Share on other sites More sharing options...
Ron NL Posted May 31, 2020 Author Share Posted May 31, 2020 Ha ha ... you allways answer my questions using 10 other (new) terms that i have to study i think you are complicating it unnessecarely . 1) its simple ... (assumption) the cameras (or sensors) look at the sun from the same direction as earth. 2) (assumption) so what the cam/sensor is seeing is what could be seen from earth also. (provided nothing blocks it) 3) If you see something ...it means that what you see is directed at you ..otherwise you dont see it. 4) To see a light from a source ...you dont have to be right in front of it ... since such light could have a wide angle. Please tell me point by point what is wrong with the above Link to comment Share on other sites More sharing options...
Jesterface23 Posted May 31, 2020 Share Posted May 31, 2020 There is a simple mix-up. You quoted "not aimed at Earth". It was actually about Coronal Mass Ejections. The full quote, "A small coronal mass ejection became visible on the SOHO/LASCO coronagraph following the M-class event but due to the location of the eruption, it is of course not aimed at Earth." Massive CMEs can span around the Sun over 180 degrees, but this one was small and hardly visible in coronagraph imagery. 1 1 Link to comment Share on other sites More sharing options...
Vancanneyt Sander Posted May 31, 2020 Share Posted May 31, 2020 No, we don't make it more complicating. We just stick to the facts. 1) measurements of x-rays is done by a sensor on a GOES satellite. These are pointed at the Sun. 2) it measures solar x-rays coming from the Sun, expressed in watts / m-2. Flares just behind the limb can be recorded as a lower magnitude because a part was blocked by the visible solar disk . This wasn't the case here as the magnetic loops where already above the limb. 3) you can see a CME in LASCO imagery but doesn't mean it is Earth directed. There was also no proton event and no electron event indicating a part was Earth directed. A magnetic complex sunspot region that's nearing the center of the disk has an increased possibility of Earth directed events even if its' nearing the other limb due to the effect of the Parker spiral. First particles of a strong solar flare arrive after 8 minutes: the solar protons and electrons (see EPAM and proton monitor), nothing was registered so not aimed at Earth. 4) only with real strong solar flares (particular long duration events) will have a proton event at Earth even if it's on the limb and even if the accompanied CME wasn't Earth directed. But not these minor impulsive solar flares. 2 Link to comment Share on other sites More sharing options...
Marcel de Bont Posted June 1, 2020 Share Posted June 1, 2020 I am not sure if I can make it more simple but will give it a go: in the article we talked about the coronal mass ejection which is basically a massive cloud of solar plasma. These clouds can be very big and wide but also very narrow or small so to speak. The location on the Sun where the plasma cloud is being launched from is very important when it comes to if it is directed towards Earth or not. The coronal mass ejection from the M1.1 solar flare was very small and slow. Just a little solar puff. Due to the location on the Sun where it was launched from this little plasma cloud has no chance to reach us as the eruption took place at the solar limb as seen from Earth. We want sunspot regions near the center of the earth-facing solar disk or just right of this sweet spot from our planet's point of view... those have the greatest chance to be earth-directed. However, if we are talking about the light or radiation emitted by a solar flare, this radiation did arrive at Earth. GOES registered the flare and as you can imagine with a light bulb, this light from the flare is being emitted in all directions. This radiation did cause a minor R1 radio blackout on the earth-facing side of the Sun. Understanding the difference between the radiation emitted by a solar flare and the resulting coronal mass ejection is key here. 1 Link to comment Share on other sites More sharing options...
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