the reflector: january 2010...la) first marketed a 5-pound radio/phone (handi-talki) to the u.s....

Newsletter of the Peterborough Astronomical AssociationThe ReflectorVolume 14 • Issue 4

April 2015ISSN 1712-4425peterboroughastronomy.comtwitter.com/PtbAstronomical

For those of us in the northern hemisphere, win-ter brings long, cold nights,

which are often excellent for sky watchers (so long as there’s a way to keep warm!) But there’s often an added bonus that comes along when conditions are just right: the polar lights, or the Aurora Borealis

Ethan SEigEl

The Cold Never Bother Me Any

Auroral overlays from the image spacecraft. Image credit: nasa Earth Observatory (Goddard Space Flight Center) / Blue Marble team.

around the North Pole. Here on our world, a brilliant green light often appears for observers at high northern latitudes, with occasion-al, dimmer reds and even blues lighting up a clear night.

We had always assumed that there was some connection be-tween particles emitted from the

Sun and the aurorae, as particular-ly intense displays were observed around three days after a solar storm occurred in the direction of Earth. Presumably, particles originating from the Sun — ion-ized electrons and atomic nuclei like protons and alpha par-

see “Aurora” on page 16

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President’s Message

The Reflector is a publication of the Peterborough Astronomi-cal Association (P.A.A.) Founded in 1970, the P.A.A. is your local group for astronomy in Peterborough and the Kawarthas.

The Reflector

www.peterboroughastronomy.com • [email protected] Phone: 705.292.0729Club Mailing AddressRodger Forsyth, PresidentPeterborough Astronomical Association536 Robinson Road RR #1Peterborough, ON K9J 6X2

Hurray Up Summer

Thanks, PAA membership, for your generosity

So far spring has begun much the same as last year. Cold. We’ve had some clear nights but the cold has

spoiled the enjoyment of night-time view-ing.

On March 28th we held our annual event recognizing Earth Hour on Armour Hill. With a well advertised event we had a tre-mendous turnout with estimates of 200 to 250 people showing up. This included a bus that came from Oshawa with 28 cub/scouts and 6 adults. Kudos to the members that helped make this event such a huge success.

Once again the paa will have represen-tation at the Peterborough Regional Sci-ence fair to be held at Trent University on April 28th. We will have some judges there and will be presenting the Frank Hancock Award to the best astronomy related project and a one year family membership to the runner up.

The following message gets repeated every year as it still applies.

Looking ahead we need to focus on “As-tronomy on the Hill” in May. You might ask “how can I help I don’t have a telescope?” We need lots of help. You can help by man-ning the traffic control on Saturday night. Greeting people and letting them know what we are doing. On Sunday we could use help interfacing with the public and keep-ing an eye on equipment when a member needs a washroom break. There are many ways you can help. Come out and get in-volved.

Reminder dues are due. The password to the paa website changes April 1st.

Rodger Forsyth PAA President

Our meeting on Friday, March 6 raised $205 for Trish McCloskey’s benefit. Trish has been a very active member of the PAA, helping out at numer-ous astronomy events. Now Trish is living with ALS, also known as Lou Gehrig’s Disease. Your generosity will help make her life just a little more comfortable. Trish has always been a fighter, so thanks for standing by her side. And a special thanks to Ken Seale for helping to make this such a successful sale.

Trish and Rodger at last year’s Astronomy Day. An enthusias-tic volunteer, Trish has also served four terms as a Judge and Award Presenter at the Peterborough Regional Science Fair.

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See “Earth Hour” on page 15

This year’s Earth Hour event on Armour Hill was the paa’s 7th year of hosting, but I would venture

to say that this year was the best. From the perspective of media coverage, weather conditions, public uptake and member participation, it was a huge success. At least several hundred people showed up on The Hill between 7:30 and midnight. The skies were clear as could be and though the wind had a bitter bite, most people dressed for the occasion. Early on, there were easy twi-light targets like a 8-day old Moon, Jupiter and Venus. As the night wore on, there was the Great Orion Nebula (M42), Comet Lovejoy and the Pleiades (M45). The public had their pick of telescopes and binoculars to view through and they took advantage of them all. There were at least two sets of large ocular binos and several each of Dob’s, sct’s, refractors and a Mak. My count put the members that were involved to about 14! We needed all these hands on deck

to handle the parking, information and equipment. A big “Thanks” to all those that came out, it was a success because of your efforts. Besides the usual suspects, there were a couple of members from as far away as Whitby (Thanks for the coffee, Gary and Barbara) and it was so nice to see Trish out with her light bracelets, everybody loves them!

The big surprise was the bus load of Cubs from Oshawa who used this opportunity to see the sky with the paa by coming to us in-stead of trying to get us down to them. We even had a vehicle load of young folks from the Belleville area because they heard on the radio that we were having this event and figured it would be worth the drive. I don’t think they were disappointed. The number of families and their kids were encouraging to see and many asked about when the next opportunity would be to “do this again”.

Earth Hour 2015 with the PAA


See “Rosetta” on page 15

John CroSSEn

I magine sitting in a control room in Darmstadt, Germany and trying to rendezvous your spacecraft with a

2.5-kilometre-long snowball more than 6 million kilometres away. Your job is further complicated because that snowball is travel-ling at 35,000 km/h. At this speed you could go from Buckhorn to Peterborough in less than a second. And did I mention that the distance from Earth to that snowball is so great that radio commands take more than 28 minutes to reach the craft? Yep, that too.

To successfully achieve this took years of preplanning, training, precise skill and a pinch of luck. But compared to cozying up to Comet 67P, touching down on its unseen surface with the Philae lander was a truly terrifying experience.

Once Rosetta was safely nestled in its orbit about 22 km along side the comet, the craft was manoeuvred into a slow orbit around Comet 67P so that the onboard cam-eras could image the surface in search of a landing site. As usual, the scientists wanted the most interesting site and the engineers favoured the safest site. Once an appropri-ate compromise was reached the Philae lander was released. Thus the lander began its 7-hour gravitational drift towards 67P. Of course the comet was rotating at about the same speed as the hour hand on your watch. Could anything be more difficult?

Touch down was made with amazing precision. Impact speed was just about the same as the tempo of you and me walking

PHILAE ON COMET 67P. The Philae lander as imaged from the Rosetta spacecraft. It has been an amazing jour-ney and is fully expected to deliver a barrage of information about planetary formation and whether comets could have delivered amino acids, the building blocks of life. Photo by ESA.

The Rosetta Mission — Part 3 Touch Down of Terror


See “Jovian Moons” on page 13

John CroSSEn

Jupiter’s Moon System. Counting Jupiter’s moons will drive you crazy. And these are just the named moons, there are plenty more.

When it Comes to Moons, Jupiter Outshines Them All

Not only is Jupiter the larg-est planet in our solar system, it also has the largest number

of moons — 67 at the last official count. Counting moons has its ups and downs. Back when Ford Galaxies had fender skirts and I was in high school, Jupiter had a scant 12 moons. Later that shot up to 16, then 23, then 40-some and eventually we got to 67.

But along the way some counts were considered official while others weren’t. Disagreement between astronomers and astronomical groups also caused the moon count to fluctuate. So if your recollection of Jupiter’s moon count is off by a few

dozen it probably isn’t your fault. Today everything is locked in at 67 official moons. Well … until another one comes along.

One key reason for the rise in Jupiter’s moon count is constantly improving equip-ment. Both telescope design and detection techniques have come a long way since I wore my powder blue tux to the Senior Prom. Also there are more astronomers working on projects that involve Jupiter’s moons.

Many of Jupiters most-recently-discov-ered moons are little more than rocks a few kilometres across. They surely aren’t round like a moon should be. Astronomers usually


Motorola Radio Phone. From hell phone to cell phone in just 73 years. The year was 1942 and a company named Gavin Manufacturing (later to become Motoro-la) first marketed a 5-pound radio/phone (Handi-Talki) to the U.S. military.

John CroSSEn

See “Sci-Fi” on page 15

Science Fiction Inspires Science Fact

The distance from fiction to fact can be remarkably short. My case in point, the Nautilus submarine in

Jules Verne’s 20,000 Leagues Under the Sea. The book was first published in 1870 and had been available in serialized form a year earlier. Surprisingly a vessel such as the Nautilus already existed, albeit in a much more primitive form.

Christened the Ictineo I, this submarine was designed for pearl divers in Barcelona, Spain. Its inventor Narcís Monturiol i Es-tarriol also invented the air scrubber which prolonged the diver’s ability to remain un-der water as well as the double hull design which allowed water to enter the outer hull as ballast. Its depth maxed at 60 feet.

Ictineo I didn’t contain the fabulous dining facilities, onboard marine museum or undersea observation room of Verne’s novel. Even its hull was made of traditional wood. But it was an important step in sub-marine hull design. Perhaps in this instance science fact inspired science fiction. What-ever, the two were born at nearly the same time.

Ever wonder how the taser got its un-usual name and where the concept came from? Tom A. Swift’s Electronic Rifle was the inspiration for its name. The gun was designed by Jack Cover, a Nuclear Physi-cist who worked for nasa on the Apollo Program. Cover had read a number of Tom Swift novels which highlighted adventure, inventions and technology. The series was conceived by Edward Stratemeyer and penned by a number of ghost writers under the shared name of Victor Appleton.

The hero of the series was Tom Swift who, among a number of other things, invented a rifle that would only stun an animal, thereby allowing its capture for sci-entific study. Obviously the concept stuck

and Cover’s taser is an acronym for Tom A. Swift’s Electronic Rifle.

As a side note, Tom Swift also invented (in his books) the electric train and the magic camera (movie camera) before either became a reality. Tom also invented a tele-phone with pictures in one of the novels. And you thought your iPhone 5 was a hot new thing!

In short, if someone can imagine it, someone will invent it — though it often takes advances in other technologies to bring the eventual product to life.

I can still remember the old radio tele-phones that Motorola made for the military. They weighed up to five pounds and were about a foot tall with an antenna poking out of the top. The big problem with them was battery technology. The battery took up most of the structure and had a 30-min-ute operating cycle before a new one was


Artist’s rendering of JPL Chopper. If the JPL Heli-Drone proves useful on the next Mars rover, you can look for a larger and more sophisticated model for the flight after that. Meanwhile the toy manufacturers are waiting with bated breath.

Heliport on Mars?

John CroSSEn

OK, so we’re going to fly all the way to Mars in a tiny helicopter like the kid down the street got for

Christmas? It might sound silly at first, but the benefits could be tremendous.

Everyone from the military to the local news station traffic reporter use drones to gather information. While there aren’t any traffic jams on Mars yet, a helicopter sur-veying the terrain ahead would be a great aid in plotting the safest, most efficient course for the rover to travel.

While the rover might not be able to see over a barrier of rocks ahead, the helicopter could fly over them and use its camera to give the rover a look. If it’s safe on the other side of the rocks, over the rover goes. If not, the crew back on Earth will plot a new course around the obstacle. And chances are the helicopter can aid in plotting that new course as well.

The helicopter can cover more distance and do so more quickly. This way it can also find areas of interest for the rover to visit

with all its scientific gear. Of course the little chopper can also take close up images of rocks and rock formations not to men-tion being on constant vigil for signs of previous Martian life. And did I mention that the little firefly can go places and land that the big rover can’t?

It makes sense to me, but how do you make a helicopter that will work on Mars? The folks at Jet Propulsion Labs (jpl) are working on that right now. In their favour is the fact that Mars’ gravitational pull is just 3/8ths that of Earth. But after that, it’s all down hill.

Mars’ atmosphere is thin, just one per-cent that of Earth. So to get the necessary lift you’ll either need massive rotor blades which are clumsy and not space efficient in a cramped space capsule or you’ll have to use smaller blades and spin them fairly fast, like 2,400 rpm.

The design team at jpl currently are working on a 1 kilogram chopper that will

See “Mars Chopper” on page 15


Photo Gallery

A Pair of Pairs

March 22nd saw another nice conjunction of a waxing crescent Moon and Venus. With a separation of only 3 degrees, they were a striking pair high in the evening twilight. The earthshine effect on the Moon was dramatic as usual, with Earth reflecting light upon the darkened side of the Moon. It was reminiscent of the grouping with Mars last month (February 20th). From where I was able to image south of Peterborough on the Crowley Line, I found a pair of silhouetted trees across a field that to me mimicked (spatially) the celestial pairing, both in their own stark beauty.

(Canon 400d tripod mounted with Sigma 18-70mm, iso 400, ƒ/4.5 for 8 seconds).

Keep looking up,

Rick Stankiewicz


There is a new (nova) star in the sky. It has been there for a long time, but it is just now reveal-ing itself to us. This powerful little white dwarf has been feeding off a companion star until the gasses it had siphoned off fuse and explodes and the resulting effect is what we see as a nova. It may have increased in brightness over 50,000 times! This actually happens all the time, but not always this bright or easy to see. Nova Sagittarii 2015 No.2, was just discovered in the middle of the constellation of Sagittarius on March 15, 2015 by an Australian amateur astronomer.

If you are familiar with the asterism of the “teapot”, this nova will be easy to find by compar-ing a star chart of Sagittarius with what you will see with your binoculars. There should be an “extra” star in the field that does not show on your chart. Compare the image attached here with any star atlas and you’ll see what I mean. If you want to see it, you better hurry because there is no telling what will happen next. It was continuing to get brighter, but this did not last long. It could be gone as quick as it appeared. The image in this article was taken at about 5:30 a.m. on March 23rd (iso 800, 50mm lens at ƒ/4.5 for 30 seconds). I had read recently that the nova was to have been naked eye and about magnitude 4.4, but I could not see it clearly the morning I was out. From my images, I would have pegged the nova at closer to 5.5 (maybe it’s dimming?). Time will tell what will become of this “new to us” star. Usually you require a telescope to detect a bright spot in a galaxy, somewhere far, far away. All you need for this one is a clear morning, an unobstructed view to the south 1 ½ hours before sunrise with a pair of binoculars. At only 15 angular degrees above the horizon, clouds can be an issue.

It may not knock your socks off, but it is a unique piece of our galaxy’s history. Catch it while you can because you never know when you will get another opportunity this easy. There are lots of Messier Objects to hunt for while in the area too. So bundle up and get busy.

Keep looking up, Rick Stankiewicz

Catch a “Nova” Star

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riCk StankiEwiCz

The Green Auroras of St. Patrick’s Day

I ask you, “What are the odds of having auroras on St. Patrick’s Day and green no less?” This is exactly what happened this past March 17th. The previous evening the Earth had been hit by a good blast of solar winds carrying its charged particles and there was a big display of auroras borealis, but of course it was cloudy across south-ern Ontario that night so we couldn’t see anything. I figured there was a chance that the Earth might still be feeling the effects of those solar winds, so after supper I checked the skies over my house and there was nothing but stars. I then checked the Aurora-Watch link on the SkyNews website (http://www.skynews.ca/aurora-watch/) to see what the map of Current Aurora Activ-ity showed and I saw a ring of red, orange, yellow and green pushing further south in Ontario than I had seen in years. I grabbed my gear and headed east to get away from

the ever present glow of Peterborough’s dome of light pollution.

I did not have to drive far before I started to notice the band of aurora hovering above the northern horizon. I set-up my tripod on the side of County Road #2 and instantly started to image the green glow of an au-roral display better than I had seen this far south for a few years. The wind was bitterly cold and my fingers stared to go numb and then my batteries both died, so my session was over, but not before getting some im-ages to share. I had captured better ones, but you can hardly be choosy when it comes to auroras. You take what the heavens give you.

I used a Canon 400d camera set at 400 iso, for 20 to 30 seconds and lenses ranging from 6.5mm to 60mm and ƒ/3.5 to 4.5.

http://www.skynews.ca/aurora-watch/

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I was back home an hour later by 10:30 p.m. and that was when I sounded the “au-rora alert” with an e-mail to the paa mem-bers list. I feared that between the late hour, the cold winds and possibility of clouds roll-ing in, the odds were against anyone having a view like I just had, but it was worth a try.

I hope some of you benefitted by the alert. I know I have appreciated them in the past when I have received them from friends and family.

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StamPS

Happy Anniversary Hubble

The Hubble Space Telescope (HST) turns 25 years this year on April 24th. It was on this day that it was lifted into space by the space shuttle Discovery. This marvel of engineering has been a boon for astronomers, the scientific community and the public at large. The whole program is a consortium between NASA and the European Space Agency (ESA). The HST is 13.2m long and houses a Ritchey-Chretien design Cassegrain reflector configured mirror 2.4m in diameter. Initially, there was a serious problem with the focus of the images and it took almost 3 years and another space shuttle mission to make it fully functional.

Orbiting 553km above the Earth and its obscuring atmosphere, the HST can see and im-age objects far superior than most telescopes on Earth. It is not the only space telescope, but is the most famous and longest lived. Five Shut-tle repair missions were key in keeping the HST

operational. The last mission was in 2009. With no more space shuttles available, it is antici-pated that a slowly degrading orbit will see the telescope burn up in our atmosphere sometime between 2021 and 2032, in the meantime, long live the HST!

Famed American astronomer, Dr. Edwin P. Hubble (1889-1953) is credited with determin-ing that the universe is expanding (Hubble’s Law). He proved this by looking at the star-light coming from distant galaxies and noticed a shift in the red end of the spectrum (redshift) which indicated they are moving away from our relative position. So, it is appropriate that this telescope was named in his honour. Seen on the left hand border of this souvenir sheet is a picture of Edwin Hubble looking through the 1.2m (48”) Schmidt Telescope in 1949, at the Palomar Observatory, California. The images

continued on next page

Vo l 1 4 • I s sue no. 4 • Ap r i l 20 15 • 1 3 The Reflectorcontinued from page 5continued from previous pageJovian Moonswrite them off as captured asteroids that have been caught up in Jupiter’s massive gravitational field. Now that they have a home, they orbit the planet like a herd of wooden ponies on a very chaotic merry-go-round.

Galileo Galilee was the first human to ever see one of Jupiter’s moons. Actually he saw four of Jupiter’s brightest moons through his primitive, handmade telescope. Imagine his amazement as he watched those tiny specks of light orbit the planet night after night.

That sight was the final piece of evidence that convinced him if those moons went around Jupiter, Earth must orbit the Sun.

In a day when Earth was thought to be the centre of the universe, that kind of thinking was sheer heresy. Unfortunately for Galileo his assumption was correct and he stood behind it until threatened with death by the Church. Sadly he had to re-cant what he knew to be true in favour of a religious myth. Today those four moons are called the Galilean Moons in his honour though he couldn’t have imagined a more bizarre band of brothers.

If you like things hot, little Io is the moon for you. Io is closest to Jupiter and its highly elliptical orbit causes its insides to rub to-gether as it orbits closer, then further, then closer again to the giant planet. The result of all this internal turmoil shows up in the form of volcanoes.

Next out is Europa, the Water-world of Jupiter, once you dig through a few hun-dred km of ice. nasa thinks we might find life in this fishin’ hole.

The biggest of Jupiter’s moons is Gany-mede and winner of the face-plant award is Callisto, the most highly cratered object we know of in our solar system.

selected for this 10th Anniversary stamp sheet issued by the U.S. Postal Service, are some of the most iconic images in the HST Library. From the upper left corner to the right are four nebu-las and a galaxy. The Eagle and Lagoon Nebulas are close-up views of a much bigger structure of dust and gas clouds where stars are being born. The Ring Nebula is a shell of gas from a star that exploded 7,000 years ago.

The images you see from the HST are not what you can see with your own eyes. These images are usually taken over many hours, days or weeks of collecting image data. Filters and computer processing are required to render the final images. The HST can observe and record in visible light, but also in ultraviolet and infra-red wavelengths.

The HST looks back into time to see the light from objects that has traveled many thousands, millions or even billions of years to be recorded and eventually shared with us. Yet, planets within our own solar system are studied as well. The HST has been instrumental in many discoveries and research over the last 25 years, but it is the sheer beauty of its images that has captivated the public around the world. As evidenced by the images on this souvenir sheet. The HST has taken 100,000s of images over the years and there is more beauty of the universe to be unveiled in the years to come.

Your Astronomical PhilatelistRick Stankiewicz


The Sky this MonthMercury is at superior conjunction with the Sun on the 10th. Hidden for most of the month.Venus is in the western evening sky. Reaches perhelion on the 18th. Passes between Hyades and the Pleiades dur-ing second week of April.Mars is very low in the western eveing sky moving eastward in Aries. Disap-pears into the solar glare by mid-month and reappears mid-August.Jupiter is well placed in the mid-eve-ning sky in Cancer. Completes its retro-grade loop on the 8th.Saturn is retrograding in Scorpius and rises in the late evening.Lunar Eclipse on the 4th. Penum-bral phase begins 5:01:25 am with great-est eclipse at 8:00:16 am.Lyrid Meteors peak on the 22nd at 7 pm.

Moon PhasesFull Moon 8:06 AM April 4Last Quarter 11:44 PM April 11New Moon 2:57 PM April 18First Quarter 7:55 PM April 25

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Earth Hour

Mars Chopper

RosettaLuckily, we could tell them mid-May for “As-tronomy on the Hill” was coming up next.

Attached are a couple images from last night. One is Antonio and Jaime Morales manning a 12” Dob for a family of guests to the paa Earth Hour event. Look at those smiles!

The other image is a cityscape panorama during Earth Hour (9:15 p.m.). Kudos to Pepsico again for turning off their flood-lights. The lights might not all be out across the city, but there are improvements from when we started seven years ago.

Keep looking up,Rick Stankiewicz

leisurely along the street. Nonetheless it was fast enough that Philae bounced. Its anchors didn’t hold and the refrigerator-sized lander drifted up and sideways for nearly a kilometre. Its third bounce lasted about seven minutes as Philae gently propped itself up in the shadow of a small cliff.

If those bounce distances and times sound difficult to believe, remember that Comet 67Ps gravity is one-hundred-thou-sandth that of planet Earth. In other words, an astronaut on Comet 67P could launch into space and never return with just a single shove of the foot. Put another way, 100-kilogram Philae weighs about one gram on the comet.

Latest news indicates that the lander has come to rest in a position where its solar panels can gather some light. This means that it can continue to stream data to sci-entists back on Earth. However the most exciting part of the adventure may not come to fruition.

The lander and rover are supposed to ac-company the comet as it nears the Sun and begins releasing the vapours containing water, dust and gasses that cause a comet to have a tail. This release may push Philae away and into deep space. However Rosetta will still be along side with all its cameras and scientific gear up and running.

The mission isn’t over until December 2015, so scientists have lots to see and hear about what makes a comet, our solar sys-tem and perhaps you and I tick.continued from page 7

Sci-Firequired. Sorry rechargeable batteries and transistors hadn’t been dreamt of yet.

Advances in technology had to take a lot of steps forward on a number of fronts before today’s pocket phones with picture screens and computers came into being. Not even Tom Swift’s Picture Phone could top that.

What does the future hold? Maybe it’s time we all read a little more Sci-Fi.

be solar powered. From tip to tip of its rotor blades will be about one metre. It will fly about 4 minutes per day on a single charge and can cover half a kilometre at an altitude of 330 feet. That’ll leave enough juice to keep its internal systems warm during the fiercely cold Martian night.

The chopper will be equipped with high-resolution cameras which will take images 10 times better than any current orbital imager can. It will also have an onboard communications system that reports back to the rover.

If it makes the cut and winds up onboard the next Mars rover expedition you can bet that every kid on the block will have one on his and her Christmas list.


ArticlesSubmissions for The Reflector must be received by the date listed below. E-mail submissions are preferred (Microsoft Word, OpenDoc, ASCII and most common graphic formats are accept-able). If your article contains photso or graphics, please provide a separate file for each. Typed or hand-written submissions are acceptable pro-vided they are legible (and not too long.) Copy-righted materials will not be published without written permission from the copyright holder. Submissions may be edited for grammar, brev-ity, or clarity. Submissions will be published at the editor’s sole discretion. Depending on the volume of submissions, some articles may be published at a later date. Please submit any ar-ticles, thoughts, or ideas to:[email protected]

Next submission deadline:April 27, 2015

Meetings The Peterborough Astronomical Association meets every first Friday of each month, except July and August, at the Peter-borough Zoo Guest Services and Rotary Educa-tion Centre (inside the main entrance at the north end of the Zoo) at 7 p.m. P.A.A. general annoucements will begin each meeting with the guest speaker starting at 7:30 p.m.

continued from page 1Auroraticles — make up the vast majority of the solar wind and get funneled by the Earth’s magnetic field into a circle around its magnetic poles. They’re energetic enough to knock electrons off atoms and mol-ecules at various layers in the upper atmo-sphere — particles like molecular nitrogen, oxygen and atomic hydrogen. And when the electrons fall back either onto the atoms or to lower energy levels, they emit light of varying but particular wavelengths — oxy-gen producing the most common green signature, with less common states of oxy-gen and hydrogen producing red and the occasional blue from nitrogen.

But it wasn’t until the 2000s that this picture was directly confirmed! nasa’s Imager for Magnetopause-to-Aurora Global Exploration (image) satellite (which ceased operations in December 2005) was able to find out how the magnetosphere responded to solar wind changes, how the plasmas were energized, transported and (in some cases) lost, and many more properties of our magnetosphere. Planets without sig-nificant magnetic fields such as Venus and Mars have much smaller, weaker aurorae than we do, and gas giant planets like Saturn have aurorae that primarily shine in the ultraviolet rather than the visible. Nevertheless, the aurorae are a spectacular sight in the evening, particularly for observ-ers in Alaska, Canada and the Scandinavian countries. But when a solar storm comes our way, keep your eyes towards the north at night; the views will be well worth brav-ing the cold!

the reflector: january 2010...la) first marketed a 5-pound radio/phone (handi-talki) to the u.s....

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