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  1. Yesterday the sun launched it largest solar flare in 3 years with a M4.4 event that initially wasn't thought to be Earth facing. However it's possible that a CME might now sideswipe Earth's magnetic field on Dec. 1-2, according to NOAA analysts. The glancing blow, if it occurs, is expected to cause no more than G1 geomagnetic storms, but hey its better than nothing. Sunspot region 2786 has only just starting to rotate onto the earth-facing disk so it is hard to say if there are more sunspots hiding behind the limb but there is at least one very large sunspot associated with this suns
  2. Here in New Zealand we can see both Scorpius and Orion in the sky in the same time and this is the time of the year to do it. In the Eastern Sky, this time of the year, the Pleiades* are visible again on the horizon. Harbingers for Halloween in the northern hemisphere where now skies are grey and ravens await for the first snows, for Māori, the Pleiades are now harbingers of summer. *Matariki is the name linked to the observance of the Pleiades in the morning sky around the Winter Solstice, but only in the morning of June-July when it marks the Māori new year. Throughout the year, t
  3. Bright planets light up the evening sky. Jupiter and Mars are the brightest. Jupiter appears midway down the western sky soon after sunset. Orange-red Mars is in the north and pretty much overhead by 11pm. As the sky darkens Saturn appears just above Jupiter. Jupiter and Saturn appear close enough together to be in the same binocular view, although they will set around midnight. This happens every 20 years when Jupiter, circling the Sun in 12 years, catches up on Saturn which takes 30 years to do an orbit. The pair will be even closer next month but low in the twilight. Their apparent pa
  4. Having had a series of G1 and G2 alerts on Monday/Tuesday I can't quite determine if the major storm arrived earlier than expected or if the initial figures for Mon/Tues were just significantly stronger than forecast. The joys of space weather! only time will tell.
  5. Welcome to the site. If you are still in the learning phase, please take a look at our topic below, which you may find useful
  6. GOES magnetometer, is the next important thing and we're doing some studies as to how the effect on GOES becomes indicative of BEAMS or the potential to see beams. There used to be a choice of magnetometers, but NOAA’s Geostationary Operational Environmental Satellites (GOES) are currently limited to 1, and that is number 16, which is positioned somewhat inconveniently on the Eastern seaboard of the US at 75.2° West. On a GOES plot, GOES has a natural curve in its graph, based on the rotation of the Earth and the position of the satellite in relation to the sun ( i.e. day or night).
  7. Why do we see those stunning lights in the northern- and southernmost portions of the night sky? The Aurora Borealis and Aurora Australis occur when high-energy particles are flung from the Sun's corona toward the Earth and mingle with the neutral atoms in our atmosphere -- ultimately emitting extraordinary light and colour. Michael Molina explains every step of this dazzling phenomenon. https://www.youtube.com/watch?v=czMh3BnHFHQ
  8. The north-south direction of the interplanetary magnetic field (Bz) is the most important ingredient for auroral activity. When the north-south direction (Bz) of the the interplanetary magnetic field is orientated southward, it will connect with Earth's magnetosphere which points northward. Think of the ordinary bar magnets that you have at home. Two opposite poles attract each other! With a southward Bz, solar wind particles have a much easier time entering our magnetosphere. From there they are guided into our atmosphere by Earth's magnetic field lines where they collide with the oxygen and
  9. Aurora On : Aurora Off In my experience, the Interplanetary Magnetic Field, or Bz is fundamentally the aurora on and off switch. Although there are exceptions, they are few and far between and this is applicable for all but the most hardened scientific aurora hunter. So if Bz is reading +'ve or northerly, you are unlikely to see an aurora at all. The stronger the northerly reading the less likely you are to see anything. I've been in Kp 9 conditions with a northerly Bz and not seen anything at all. However, if Bz is reading -'ve or south then you are likely to see one - if other
  10. What are these G numbers you speak of? Geomagnetic storms are labelled G1 to G5. It is a period when there is strong to very strong geomagnetic activity due to a lot of build up in Earth’s magnetotail. Here is a table which converts the G into Kp. G1 = Kp5 G2 = Kp6 G3 = Kp7 G4 = Kp8 G5 = Kp9 It's for this reason you hear a lot of people say they wouldn't get out of bed for anything less than KP5. They like their aurora potential to be strong, just like their coffee. If you waited for a KP5 event every time before going aurora hunting you'd rule out 60% of your opportunitie
  11. Usually the first sign of any potential aurora activity chatter, comes from the Kp indices forecast, such as the one below. These values indicate the expected geomagnetic activity for any given 3-hour period for the next three days. This is the fastest way to quickly find out what kind of geomagnetic conditions are to be expected over the next 3 days. The times are in UTC, which is a time standard used across the globe. For NZ daylight savings we're 12 hours ahead, so 21:00 on the 28th UTC, would be 09:00 on the 29th NZST. The Kp number system is a scale of planetary geomagnetic acti
  12. What's producing this aurora activity? The current activity seems to be from 2 solar phenomena, which may be why the alerts are coming through stronger than the associated forecast models. The dark area spreading from the northern hemisphere is a Coronal Hole. This was detected as being Earth facing on Saturday. "A transequatorial coronal hole was detected in an earth-facing position on Saturday, 26 September 2020". This means solar winds are flowing towards us, and they in turn can produce Aurora activity. A large hole has potential to do this over several days. Behind the CH is a glo
  13. Looking at the current aurora forecast for this week, sees some potential viewing opportunities. Here is the predicted Kp indices chart On this chart the times are in UTC. This isn't a time zone, but a time standard. New Zealand is currently 12 hours ahead of UTC, so 0900 on the 28th Sept would be 21:00 local time. Please feel free to reply if you have a something to say about the aurora forecast for this week. Or start a new topic if you have a question on another aspect of the aurora and how to understand the charts. We'll be putting up an information post on how to read a forecas
  14. Many people think you need an expensive camera to do astrophotography and I love to prove them wrong with my snaps on my mobile phone. All you need is a night mode or a pro mode so you can change the exposure settings manually and a solid surface. This was my handheld shot from last night. Tell me what you can see and if it's worth having a go with a phone. The daylight effect was due to the moon 🌒 and this shot is completely edit free.
  15. A plan of the night sky, looking north at 7.30pm from Christchurch
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