HAA Skywatch

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.

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.

As a service to our members and those interested in astronomy, we're providing a list of upcoming star parties that will be occurring in our general area over the next couple of months.

If you love astronomy and want to observe with lots of other like-minded people in reasonably dark skies, then you'll want get to at least one of these star parties. They are always a lot of fun and usually have interesting programs during the day. Also many of these have vendors present who offer good deals to help upgrade your equipment. You'll meet many astronomers from other clubs and pick up some observing tips. And don't miss the chance to look through the wide variety of equipment that observers will have set up. You may end up with aperture fever and eyepiece envy, but it's worth the "suffering" for the all the benefits you'll gain.

The darkness of the skies, camping facilities and programs vary significantly between each of these events. Be sure to check the websites for more details and see what is being offered. All of these star parties have been attended by at least 1 or more members of the HAA over the years and each of them can be recommended.

Star party # 1:

Stellafane - Aug 5 - 8
If you like to make scopes or see how they are made, this is the event for you.
Springfield, Vermont
Registration and website: http://stellafane.org/convention/2010/index.html

Star Party # 2:

Manitoulin Star Party - August 6 - 9
Very dark skies, fairly rustic camping and facilities.
Gordon's Park Eco Resort, Manitoulin Island, Ontario
Program: http://www.gordonspark.com/man_StarParty.pdf
Website: www.gordonspark.com

Star Party # 3:

Starfest - Aug 12 - 15
The granddaddy of them all for Canada.
Mount Forest, Ontario
Registration and website: http://www.nyaa.ca/index.php?page=/sf10/sf.home10

Star Party # 4:

Huronia Star Party - Sept 8 - 12
Duntroon, Ontario (near Collingwood)
Registration and website: http://www.hsp-ssaa.ca/HSP_Site.html

Star Party # 5:

Black Forest Star Party - Sept 10 - 12
Darkest skies in Eastern USA.
Cherry Springs State Park, Pennsylvania
Registration and website: http://www.bfsp.org

If you get out tonight or the next couple of nights and look West at Sunset, you will see 5 planets in a relatively close alignment. Mercury will be low and close to the horizon. Next and higher up will be Venus, Mars and Saturn. Also the Moon will be passing below the planets each night.

To best appreciate this, you'll need to find yourself a high location with a clear view to the West. Our alternate observing location on Tyneside Rd is a good candidate location since the farm across the road has few obstructions. You won't need any gear to see these.

These planets are not really close enough to be considered a conjunction, but they do make a nice alignment and wide field view.

Here's a chart from SpaceWeather.com showing the position of the planets and the Moon for the 15th (except for the Moon, it's valid for nights before and after the 15th).

The 5th planet? Your standing on it of course!

It's been cloudy for the past few days. But now we're expecting a couple of clear nights. It will be a good time to get out and look for Mars as it passes the bright blue star Regulus in the constellation Leo.

The closest pairing, as identified in the 2010 HAA Calendar, was Sunday night (June 6), but Mars will still be close for the next few evenings. Here's a sky chart showing the position of Mars in the Western sky.

And of course Saturn is nicely positioned nearby for another wonderful view. In a few months, Saturn won't be positioned as conveniently or as high in the sky so now is the best time to enjoy it.

On Fri June 11, 1 hour after sunset, Venus will be in a straight line with the 2 main stars of Gemini - Pollux and Castor. This will be a pretty sight and photo opportunity. Find yourself a good clear view to the West without city light glow if possible.

If you're an asteroid watcher, Ceres is approaching opposition (occurs on June 18) which is when this object is closest to Earth and easiest to see. It's travelling through the constellation Sagittarius towards Ophiuchus.

Path of Ceres leading up to opposition.

It's a faint object (mag 7.3), but one that most amateur telescopes 3" and larger can detect. Even a good pair of binoculars are capable of spotting this asteroid when it's this close. It will be interesting to see it change position each night. Just carefully observe the target star field and keep an image in your mind (or better is to sketch it). Then see what changes each night as you go back to the same area.

For the early morning observer, Jupiter is nicely positioned (with Uranus nearby). There was another asteroid impact on Jupiter recently (June 3). There are some videos of the flash from the impact over on Spaceweather.com.

So far no one has seen a dark spot resulting from the impact, but you may be the first to detect it. The recent impact, the one from last year, and the detection that Jupiter lost it's South Equatorial Band (SEB) was all first discovered by amateurs just like you - so you have just as much a chance of spotting the debris field as any one does. Don't forget us when you achieve international fame for your discovery!

A reminder that the Cherry Springs Star Party is coming up later this week. There are a few spots left. Today is the last full day for online registration if you're thinking about going. At $40USD, it's a good deal. A number of the HAA membership will be there. It's always a good event with lots of interesting speakers and a great location.

And be sure to check out the latest edition of our newsletter Event Horizon which is now online, for more things that will be coming up over the summer months.

Clear skies!

(images courtesy of Spaceweather.com and Skyandtelescope.com)