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Space Weather News for Sept. 5, 2010
http://spaceweather.com

SOLAR ACTIVITY: On Sept. 4th around 1600 UT, a magnetic filament erupted, hurling a bright coronal mass ejection (CME) off the sun's northwestern limb. Today's edition of http://spaceweather.com features a close-up view of the blast from NASA's Solar Dynamics Observatory. The CME is not expected to hit Earth. Nevertheless, auroras are possible in the nights ahead. A solar wind stream flowing from a coronal hole is heading our way, due to arrive on Sept. 5th or 6th. NOAA forecasters estimate a 50% chance of high-latitude geomagnetic activity when the solar wind hits. With the approach of northern autumn, Arctic nights are getting dark again--dark enough to see the Northern Lights. People in Alaska, Canada and Scandinavia should keep an eye on the night sky this weekend.

Have you seen the recent emails claiming that on Aug 27, 2010, that Mars was going to be huge, larger than it's ever been, as big as the Moon, and larger than anyone alive will ever see again? I hope you didn't believe it. This is a recurring email that appears to be sent out every year about this time - and it's a Hoax.

Being an active astronomy club and a site that many people come to look for info, it seemed appropriate that we post something about this hoax and hopefully put it to rest once and for all (perhaps I'm too optimistic).

First it may help to present some numbers to put things in perspective. Mars is about twice the size of the Moon and roughly half the size of the Earth, and orbits the Sun, like the Earth but at a greater distance. The Earth's average orbit is about 92 million miles or 150 million kilometers from the Sun. Mars' average distance from the Sun is 140 million miles or about 227 million km. So while the Earth take 365 days to orbit the Sun (1 Earth year), Mars takes 687 days (1 Mars year). On the other hand, the Moon orbits Earth at an average distance of 250,000 miles or 400,000 kilometres and doesn't change much since it's always orbiting the Earth.

Since the Earth takes less time to orbit the Sun than Mars (because it's closer to the Sun), it means that every 26 months or so, we "catch up" to Mars and pass it. Think of watching a car race around an oval track. Cars on the inside lane more easily pass those on the outside lanes because they have less distance to travel. And cars that are on the same side of the track are closer to each other (so appear to be about the same size) than those on the opposite side of the track (they appear smaller in the distance). This race track analogy will come into play again later.

When we are on the same side of the Sun (same side of the track), we are at the closest point between the 2 planets, what astronomers call Opposition. Earth's orbit is fairly circular (but not exactly) but Mars' is much more eccentric (more elliptical or oval than Earth's orbit). So sometimes at closest approach, we can be as close as about 55 million kilometers or more than 80 million km apart. (When Mars is on the opposite side of the "track" then obviously it's even further away). Now keep this in mind. The closest Mars can get is about 55 MILLION kilometers, whereas the Moon is about 400,000 km away. That's more than 130 times further. And even though Mars may be twice the size of the Moon, it can never look as big as the Moon. Consider a dime and a quarter. A quarter is about roughly twice the size of a dime. If you place a dime 5 feet from you and place the quarter 675 feet (130 times) away, the quarter isn't going to look the same size. In fact you're going to have a tough time seeing the quarter. For Mars to appear the same size as the Moon, it would have to get within about 750,000 km, and it can never get any where "close" to that distance from the Earth.

Now in these emails, which actually started back in 2003, and have now become an annual event, were very loosely based on some facts. On Aug 27, 2003, Mars did get closer to Earth than it has been in at least 5000 years, about 56 million km from Earth at its closest. The first emails came out then telling people that Mars would appear as large as the Moon. From the numbers above we know this can never happen. Mars was impressive through a telescope, but it didn't get as big as the Moon.

We had a break in 2004 when it appears the emails didn't circulate (or at least not widely). But then they appeared again in 2005 when Mars was going to be moderately close (astronomically speaking) in Oct of that year (remember we catch up every 26 months). The fact that they used the same Aug 27th date instead of Oct didn't seem to bother the originators of the email. But in 2005 Earth didn't get any closer than about 72 million km. Certainly a lot further than 56 million km we experienced in 2003.

For some reason, since then, these emails have re-appeared every year, regardless of whether we are getting to close approach of Mars (opposition) or not. In fact, right now, Mars is almost to the far side of the Sun from us, about 315 million km away - not even close. We had hit our closest approach back in Jan 2010 - quite a long time ago, and it won't be until Mar 2012 when we get moderately close again. We won't get as close as we did in 2003 for many years. I think in 2018 we'll get almost as close as we did in 2003 - but "almost" in this case is about 60 million km.

In later years the emails have taken slightly different forms and some have had minor corrections or additions. For instance, some of them indicate in small print somewhere that using a telescope with 75 times magnification, then Mars will look as big as the Moon, since the apparent size of Mars in 2003 was about 75 times smaller than the Moon. Sadly they don't make that obvious. I guess it takes away from some of the "WOW factor".

Why do they keep sending these emails? I don't know. No one is making money or "phishing" for your email address like some viruses do. So there doesn't appear to be anything malicious. But when you consider that they are spreading misinformation and causing people to believe in things that aren't true, then that's a true disservice. Sadly there is a lot of bad info on the internet, many times made to look factual. In fact one could make that claim about this post. The best way to deal with this is to arm yourself with the facts. Check out many sources, especially the main-stream scientific sources for factual information. So I'm providing some links below to help you research this subject or to get more information.

This link is for Snopes which talks about modern folklore and various stories, identifying which are true and which are false. This particular link is for one of the entries over the years for this False claim.
Mars Hoax

This is a recent NASA article talking about the hoax.
NASA

Bad Astronomy, which I have referred to several times in the past, has a lot of articles and blogs postings about various hoaxes including this one. Many of the blog postings contain additional references and resources. Some of them can be found HERE and HERE.

And Universe Today has a good article from 2007, but still relevant, debunking this misinformation at Mars Hoax

You'll notice that most of these references are old. That's because this hoax keeps reappearing and scientists keep trying to correct it, and yet it keeps coming back each year.

I encourage you to read these articles and seek out others. And of course, when you see these emails in the future, and they inevitably will re-appear again next year, please don't forward them on to your friends. Let's put an end to this nonsense.

"Clear skies? Must be full moon." A sarcastic statement but all too true this week! Many of our members found the lure of clear summer skies and warm temperatures too tempting to resist last night and again tonight (Friday and Saturday).

The ISS passed overhead both evenings. Tonight the seeing was excellent and I had a great view of Jupiter through John's "small but mighty" 80mm refractor. Kevin's 10" Dob. pulled in B86 and the adjacent globular cluster, NGC6520 and gave breathtaking views of M11, M22 and M15.

I tried taking some untracked, unguided photos of the Milky Way through Sagittarius.

Now, if we can only save some of these clear skies for new moon....

Just by chance, I stepped outside last night for some fresh air and as I often do, I looked up. And just as I was looking to see what was visible from the backyard, a bright light was moving through the sky. My experience told me it was a satellite and not an airplane. I momentarily thought it might have been an Iridium flare, but the size seemed too large. So my guess changed to the ISS (International Space Station).

Once it had faded and moved into Earth's shadows, I went back in to visit the Heaven-Above.com website which has transit times for many satellites, and confirmed that it was indeed the ISS and I just happen to catch the 20-30 seconds that it was passing overhead. I also noticed that we're going to have a number of additional passes for the next 4 or 5 nights. Ann suggested I make this info available to members and the general public. Always interesting to see the ISS pass overhead. And if you have time to prepare, you could try using binoculars to see some structure.

So as a public service, I'm posting some of the upcoming ISS passes for your observing pleasure. Remember that for basic observing of the space station, you don't need any equipment. It's bright enough that when the skies are clear, you can see it with just your eyes - it will look like a bright airplane, but without the flashing coloured lights. (Binos and telescopes may allow you to see detail which you can't do with just your eyes, but it's harder to track when it moves across the sky).

How to read this info:
Date and Time should be fairly straight forward. The time shown is local for the Hamilton area using the 24 hour clock. The times shown are in the evening.

Mag - (Magnitude) this indicates how bright the ISS will be with larger negative numbers being brighter. Venus (presently in the Western sky after sunset) is currently about -2. So a -3 pass will be brighter than Venus.

Track - this is a rough guide where to start looking for, and the direction that the ISS will take as it crosses the sky. At the designated time, look in the specified direction at about 30 degrees above the horizon which is roughly where you should first spot the ISS. Then follow it's path when it crosses the sky. Usually the brighter passes will become visible earlier and last longer, but at most a pass will only last a couple of minutes. Usually they are more in the 15-30 sec time frame. Some won't get very high above the horizon (trees and houses could be a problem). Others will pass nearly overhead. For the "NW to NW" appearances, this indicates that the ISS will only appear briefly in the general NW area of the sky and not very high above the horizon.

Most of the brighter passes will occur this weekend and fortunately the forecast is expected to generally be good.

I've tried to simplify the info from the Heavens-Above website, so what's listed below won't be exactly as you would find on their site. More details and info can be found at:
Heavens-Above for Hamilton
This info is current as of Thu Aug 26.

   Date     Time    Mag    Track      Notes
Thu Aug 26  20:23  -2.4   SW to E   won't get high in sky
Thu Aug 26  21:58  -2.3   W to NE     

Fri Aug 27  20:50  -3.7   SW to NE  will pass nearly overhead
Fri Aug 27  22:26  -1.1   NW to NW  appears just above horizon

Sat Aug 28  21:17  -2.0   W to NE
Sat Aug 28  22:54  -0.2   NW to NW  appears just above horizon

Sun Aug 29  20:09  -3.5   SW to NE  will pass nearly overhead
Sun Aug 29  21:46  -1.1   NW to NE  won't get high in sky

Mon Aug 30  20:37  -1.8   W to NE
Mon Aug 30  22:14  -0.8   NW to N   appears just above horizon

Tue Aug 31  21:05  -1.1   NW to NE
Tue Aug 31  22:41  -0.3   NW to NW  appears just above horizon

For the following dates, the ISS won't get very 
high above the horizon.
Wed Sep 1   21:33  -0.9   NW to NE

Thu Sep 2   20:24  -1.1   NW to NE
Thu Sep 2   22:00  -1.1   NW to N

Fri Sep 3   20:52  -1.0   NW to NW
Fri Sep 3   22:27  -0.5   NW to NW 

Hopefully there will be lots of clear evenings and you'll have a chance to see the ISS. You don't need a particularly dark location, just a clear view of the path. If you don't have trees or home in your way, you can see the ISS from the city.

Happy hunting.

Hey everyone,

I had a great time out at Binbrook with the HAA gang on the 'members persied meteor night'. This was my first time out there in a really long time so it was especially nice to see everyone and catch up. For the first hour or so a few of us took pictures of the scenery with the moon, venus, mars and saturn. Later in the night we joined the the rest of the group who were already watching the meteors. I saw a few really bright ones with smoke trails and many numerous smaller ones. Since I had my celestron 15x70s with me I did a quick tour of the summer constellations. A few of the objects that were easily visible were M71 globular cluster, the coathanger asterism, M27 Dumbell nebula, M11 wild duck cluster, m8, m20, M16 and M17, and M22. M22 a bright globular cluster in Saggitarius was most impressive.

Venus and the Moon

Venus reflecting on the water

Relaxing under the Milkyway

On and off over the past several months I have been working on a collaboration with Paul Mortfield. This part of the sky is very murky with lots of dust shrouding the golden stars in the Milkyway. Hope you like it!

Click for image details and higher resolution:
http://www.weatherandsky.com/main.php?g2_view=core.ShowItem&g2_itemId=8056&g2_imageViewsIndex=2

KerryLH