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  2. Norwegians have been left awestruck by a bright meteor that illuminated the night sky in the country's south-east. Footage shows powerful flashes of light over Norway, followed by what witnesses described as loud bangs on Sunday. Norwegian police say they received a flurry of emergency calls but there were no reports of injuries or damage. A team of experts are hunting for the meteorite, which they believe landed in a forest near the capital, Oslo. A meteor is a space rock that burns brightly after entering Earth's atmosphere at high speed. It becomes known as a meteorite if it survives its passage to the ground. The Norwegian Meteor Network says Sunday's fireball was visible for at least five seconds after it appeared at about 01:00 local time (23:00 GMT). https://www.bbc.com/news/world-europe-57962384
  3. Three New Zealand photographers are in the running to win one of the world’s most prestigious competitions, the Astronomy Photographer of the Year. Organised by the Royal Observatory Greenwich in the UK, more than 4500 images from 75 countries have been submitted. One of those shortlisted comes from Auckland-based Larryn Rae. His image, entitled Iceland Vortex, is a 250-degree panorama shot of the Aurora Borealis in Iceland. Evan McKay’s Three Sisters captured at Tongapōrutu in Taranaki is another shortlisted for Astronomy Photographer of the Year. Mathew Ludgate’s The Spider’s Web is an image of the Large Magellanic Cloud (LMC), the largest satellite galaxy of the Milky Way. https://www.stuff.co.nz/travel/news/125651176/kiwis-in-the-running-for-one-of-the-worlds-most-prestigious-photo-competitions
  4. ****Limited tickets are now available**** The focus of this special evening is the Lunar Eclipse, we will view the moon in detail, or if conditions and time allows, see fascinating open clusters and nebula. Our local dark sky tour guides are keen stargazers and can talk you through the various delights of the southern night sky. The astronomy tour is aimed at adults (due to the duration and time of night). You are welcome to bring your DSLR camera and tripod and we will endeavour to assist you to get the most from your night of widefield astro photography. An aurora forecast is anticipated to produce an aurora, but conditions cannot be guaranteed. The evening will cover how to maximise your chances of how to see aurora and what camera settings to use for those that are interested. We have a heated room, and toilets available throughout the evening. You are welcome to bring food and a flask containing a hot drink, outside seating, warm rugs or a duvet with you so that you can sit and relax outside, either on grass or asphalt surface. If you bring a torch, please make sure it is RED light only. Please note: Alcohol is not allowed on site. VERY limited tickets available http://chchastrotours.eventbrite.com/ #christchurchnz #exploreCHC #sensationalselwyn #lunareclipse #moon #aurora #auroraaustralis #astrophotography #astrophoto
  5. All the best laid plans come together at the last minute. As you will already know on Wednesday there is a lunar eclipse. We're also forecast lovely clear skies. And to top things off, there is an Aurora forecast allegedly giving us G2 or G1 storm conditions. Sooo, the question is, would you be interested in coming along for a combined session, something like 8 to 11.30pm? Bring tripod, DSLR cameras and we could guide you through how to get the best from your DSLR and you could get some lunar scope time and explain some of the night sky to you We could cater for upto 10-12 people, with warm room, toilets and a kitchen space. If there is enough interest, we could put something together - approx $80-100 price range due to length of time of the session. Let us know by replying below.
  6. We had a fantastic night last night with our group of guests with cold clear skies giving some great viewing conditions. A combination dark sky tour of "faint fuzzies" and a lunar tour as the moon rose helped complete the night. It made for an eventful viewing session. One of our favourite faint fuzzies at this time of year is the Sombrero Galaxy or NGC 4594. If you look at a Nasa image you can see how it gets its name Image Credit: NASA, ESO, NAOJ, Giovanni Paglioli, but to us on the ground, with our night vision enabled eyes it becomes a little less spectacular, until you get some perspective. Sombrero is another galaxy, some 31 Million light years from us, and 49,000 light years across. With our closest solar neighbour approx 4 light years away, the 2nd image is a rough approximation of what we could see through the telescope last night as the moon was rising. The light from Sombrero takes 31m years to reach us, it was from a time when Earth was in the Oligocene period and some 4-6 degrees C warmer than it is now. The first human ancestors appeared between five million and seven million years ago, probably when some apelike creatures in Africa began to walk habitually on two legs. "Humans" were flaking crude stone tools by 2.5 million years ago. Then some of them spread from Africa into Asia and Europe after two million years ago.
  7. The headline is a little vague because these were definitely starlink and whilst the do generate interest from the general public they are a nightmare for astronomers who want to image the night sky. With the coming launches it's likely we'll see starlink satellites during our observations throughout the season. https://i.stuff.co.nz/science/124530354/strings-of-light-crossing-the-sky-high-overhead-likely-to-be-a-starlink-chain
  8. A Nasa rover is making its attempt to land on Mars in the riskiest step yet in an epic quest to bring back rocks that could tell whether life ever existed on the red planet. Perseverance is entering the riskiest part of its landing on Mars at just after 9.45am (NZT) in which flight controllers can only watch as the spacecraft hurtles toward the red planet, long a deathtrap for incoming spacecraft. It takes a nail-biting delay of 11½ minutes for a signal that would confirm success to reach Earth.
  9. Tonight, just after dark, should be an ideal opportunity to see the conjunction
  10. I managed a glimpse during the latter half of last week, nothing over the weekend, due to the cloud, but tonight is the closest we will see.
  11. Jupiter is moving closer to Saturn and they will be less than a full-moon's width apart between December 17th and 26th. Around the 21st-22nd the gap between then will be about a quarter of a full moon's width, so they will be in a telescope's field of view. These close encounters (called conjunctions) happen every twenty years when Jupiter, orbiting the Sun in 12 years, catches up with Saturn, which takes 30 years to do an orbit. The close pairing is just line-of-sight, because Jupiter is 879 million km away and Saturn 1,610 million km away. The crescent Moon will be above the pair on the 17th. Mars is due north at dusk Please feel free to reply if you have a something to say about the planets during December, or need help finding them. Or start a new topic if you have a question on another aspect of the December night sky.
  12. When Jupiter and Saturn—the two biggest planets in our solar system—meet, it’s termed the “Great Conjunction.” What’s even more special is that it’s happening on night of the winter solstice This is the rarest meeting between any of the five bright planets. It happens just once every two decades, and 2020 brings the closest Jupiter-Saturn conjunction since 1623, during Galileo’s times. Simply speaking, a conjunction occurs when planets or other objects appear to be very close to each other on our sky’s dome. These “meetings” or conjunctions in the sky are fairly frequent, especially when it comes to the Moon passing the different planets in the sky. From our point of view, the two giant worlds will appear only 0.1 degrees apart. That’s just ⅕ of a full Moon diameter. Unlike previous conjunctions, this one’s not obscured by the Sun’s glare, either, so we get to see it. Only if you can hold out until March 15, 2080, will you see a Great Conjunction as good as this one. Actually, that one, low in the eastern sky before dawn, will even be better, since the two giant planets will seemingly merge into a single brilliant star or rare double planet. Which is what some are saying about our current Great Conjunction. if you’ve got trees or neighbours’ houses or hills in the direction of sunset, you’ll want to check out the planets a few evenings beforehand at that same time so you can be sure they’ll be in the clear on the solstitial evening. Unfortunately, this will be a one-night affair. The day before and the day after, the planets will be noticeably farther apart and nowhere near as striking. So if the weather cooperates on the 21st, you’ll want to get all you can out of the spectacle. Binoculars will be a nice adjunct, and will easily reveal Jupiter’s four huge satellites spread in a straight line. Saturn will be off in a different direction, perpendicular to those moons. The two images represent 20th and 21st December from Christchurch at 9pm
  13. The ghostly ORC1 (blue/green fuzz), on a backdrop of the galaxies at optical wavelengths. There’s an orange galaxy at the centre of the ORC, but we don’t know whether it’s part of the ORC, or just a chance coincidence. https://i.stuff.co.nz/science/123581259/wtf-newly-discovered-ghostly-circles-in-the-sky-cant-be-explained-by-current-theories-and-astronomers-are-excited
  14. 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 sunspot region.
  15. 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, the Pleiades is the prow of Te Waka o Takitimu, in November, when it is visible again in the evening sky, the Pleiades cluster is not Matariki but the feathers of the waka o Tama Rereti. Together with the Hyades they make the wake and feathers from the Great Canoe (Waka) of Tama Rereti. November is the month when Milky Way surrounds the horizon like an ocean and the Great Waka was used by Māori to mark the arrival of the warm season when it was safe to travel the ocean. Tama Rereti’s Waka placed the stars in the sky and now lies moored in the wake of the Milky Way. Scorpius is Tauihu, the prow, floating low on the western horizon. Due south sits Te Punga, the anchor (the Southern Cross), with its rope, Te Taura, which is represented by the Pointers (Beta and Alpha Centauri). The latter is actually a multiple star system that holds our closest solar neighbour, the red dwarf Proxima Centauri, at 4.25 light years from Earth. The sails of Tama Rereti’s canoe are Achernar and the beautiful southern dwarf galaxies the Small and Large Magellanic Clouds (SMC and LMC). Canopus/Atutahi is the paramount chief of the skies at vigil in the waka. A source of X-rays and the most luminous close star at 310 light years from the Sun, Canopus is used for navigation by all spacecraft that employ star tracker devices, which determine the orientation (or attitude) of the spacecraft with respect to that star. Te Taurapa, or the stern of the waka is in the Eastern Sky, formed by Orion.
  16. 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 pairing is just a line-of-sight effect, of course. Jupiter is 830 million km from us, mid-month, while Saturn is nearly twice that distance, 1560 million km away. The moon, just 374,000 km away, will appear near Jupiter on the 19th. We passed Mars in mid-October and are now leaving it behind us. As we do it will slowly fade. It will be 80 million km away mid-month. The moon will be near Mars on the 25th and 26th. Venus rises a little south of east an hour before the Sun all month. Mercury might be seen in the dawn mid-month, below and right of Venus, and much fainter, rising 35 minutes before sunrise. Please feel free to reply if you have a something to say about the planets during November, or need help finding them. Or start a new topic if you have a question on another aspect of the November night sky.
  17. 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.
  18. 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
  19. 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). What we're looking for are spikes. On this chart, I've marked all of them, but we're actually more interested in the ones below 50nT as these tend to give stronger results. Our localised findings are the correlation between the upward springs and the appearance of beams in an aurora (or at the very least heightened activity). Of course, the rest of the conditions also have to be met, particularly a south Bz. The stronger the bounce back (upward) direction the stronger the beam activity gets, as the graph settles, the beams disappear. There is also a short delay between the satellite receiving the data and the arrival of the beams, this again depends on the speed of the wind, as the satellite is 6 Earth radii away. GOES is a great indication tool for NZ conditions, especially when conditions are less than KP5. However remember we need a southerly Bz to see aurora. In basic terms we need the GOES16 magnetometer to head towards 50 nT. Think of this as an elastic band being stretched back. If you recall the images from the previous units, we're looking for a snap back of the magnetic flux. So the lower the number the further back the band is being stretched. Now lets release the band. If it jumps back up quickly, like on this graph, it may produce beams, they could be bright, but it would be very short lived, because the snap back was quick. A slower snap back, would produce an effect for a longer period of time, but the effect may not be as bright, or may not "beam". The correlation was first noticed in NZ Aurora circles by Geoff Cloake, so we affectionately call this the "Cloake Effect". I've not had it fail me, which is why I use it as the primary indicator for Aurora potential, even when KP is as low as one. In those conditions we may only get a low grade photo quality green arc, but it would nevertheless be an aurora. https://www.swpc.noaa.gov/products/goes-magnetometer
  20. 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
  21. 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 nitrogen atoms that make up our atmosphere, which in turn causes them to glow and emit light. For a geomagnetic storm to develop it is vital that the direction of the interplanetary magnetic field (Bz) turns southward. Continuous values of -10nT and lower are good indicators that a geomagnetic storm could develop but the lower this value goes the better it is for auroral activity. Only during extreme events at higher latitudes and with high solar wind speeds it is possible for a geomagnetic storm (Kp5 or higher) to develop with a northward Bz.
  22. 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 conditions allow. Any -'ve reading is good, but the stronger the better. Bz changes in an instant, so DO NOT write of a night hunting because Bz is not currently favourable. The instrumentation for this reading sits on a satellite called DSCOVR, some 1.5 million km closer to the Sun from Earth. So depending on the speed of the solar winds, its arrival time on Earth can differ from the time it reaches the satellite. However that gives us advance warning of the conditions, so everything to the right of the Earth line is what's coming.
  23. Very excited about the next few days, if the weather clears. Only just started learning a few years ago and excited to visit the observatory soon as have now moved to Christchurch
  24. 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 opportunities of seeing one. Let's face it a single shot Americano is still a coffee and Kp3 and 4 are readily visible from the Christchurch area.
  25. 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 activity. It is not a plot map where you can definitely say auroras will be visible. The Kp number is a system of measuring aurora. It goes from 0 to 9 (0 being very weak, 9 being a major geomagnetic storm with strong auroras visible). It is not an accurate gauge of how strong the aurora will be, more a case of how much potential there is to see one. I also relate it to the old earthquake Richter scale. For those of us who've experienced many earthquakes recently, you can have a Mag 4 and you can have a totally different Mag 4 that appears a lot stronger, yet both are measured the same on the Richter scale. So you as you get into it, you look at other scales, in the earthquake instance, the Mercalli scale. Aurora are no different. So when you're looking for Aurora, you want to see high Kp numbers. The higher the better. Anything above (and including) Kp5 is classed as a geomagnetic storm. I also view it as the chance of seeing an event rather than the strength of a given event. And yes, you can photograph aurora in New Zealand at Kp1 (with beams) and in the same instance we've had Kp9 and not seen a thing. If there is one piece of advice I can give you: DO NOT rely solely on Kp index when considering if there will be an aurora or not. I use the Kp forecast from https://www.spaceweatherlive.com/en/auroral-activity/aurora-forecast
  26. 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 glowing region. This is normally associated with sunspot activity and is an area that could produce solar flares. However, this region must be borderline as a sunspot has not been detected, although the output could combine in this instance with the effects of the coronal hole. Flares tend to be short but powerful bursts that produce short lived aurora.
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