Wednesday, August 02, 2006

more victims

Barbara emailed me this morning. She too received the Mars message. Believing it to be true, she asked me to bring out my telescope on the designated date. Once again, I explained to her that it was a hoax (although I'm happy to bring out the 'scope). She forwarded the message she was referring to. So I finally get to see the missive (funny that I haven't received it directly).
The Red Planet is about to be spectacular!

This month and next, Earth is catching up with Mars in an encounter that will culminate in the closest approach between the two planets in recorded history. The next time Mars may come this close is in 2287. Due to the way Jupiter's gravity tugs on Mars and perturbs its orbit, astronomers can only be certain that Mars has not come this close to Earth in the Last 5,000 years, but it may be as long as 60,000 years before it happens again.

The encounter will culminate on August 27th when Mars comes to within 34,649,589 miles of Earth and will be (next to the moon) the brightest object in the night sky. It will attain a magnitude of -2.9 and will appear 25.11 arc seconds wide. At a modest 75-power magnification

Mars will look as large as the full moon to the naked eye.

Mars will be easy to spot. At the beginning of August it will rise in the east at 10 p.m. and reach its azimuth at about 3 a.m.

By the end of August when the two planets are closest, Mars will rise at nightfall and reach its highest point in the sky at 12:30 a.m. That's pretty convenient to see something that no human being has seen in recorded history. So, mark your calendar at the beginning of August to see Mars grow progressively brighter and brighter throughout the month.

Share this with your children and grandchildren.

All right. Let's dissect this crap.
  1. This message is from the past! It is in reference to the "great apparition" of Mars in 2003. On 27 Aug 2003, Mars passed the close to Earth, the closest in a long time. I don't know about the recorded history part of it... Sounds fishy.
  2. This "recycled" message is giving the impression that Earth and Mars are getting close now, Aug 2006. Wrong. We're almost as far away as we can get at 385 000 000 kilometres (or 239 000 000 miles). In fact, Mars will move into conjunction (on the far side of the Sun from us) in October this year. We don't start moving toward Mars until November. Then it will take another year or so for us to be relatively close to Mars, where it is at opposition, on the same side of the Sun as us. So, it's the Dec 2007-Jan 2008 calendars you need to mark...
  3. Because Mars's orbit is quite elliptical (compared to ours which is more circular), it means that, at times, Mars and Earth are positioned very close physically to one another. Technically, this is orbital eccentricity: Earth is 0.017; Mars is 0.093. I believe you can calculate the proximal rendezvous simply by multiplying the orbital periods of the two planets. We're 365 days (of course) and Mars takes about twice as long at 680 days. I.e. about every 680 or so years! So, it's true that this was once-in-a-lifetime event. And if you didn't see it in 2003, you're going to have to wait until Oct 2667! I don't know where they get the 5000 and 60000 years from...
  4. That we travel around the Sun about twice as fast as Mars means there's some good news. Approximately every 2 years, Earth passes Mars. Some years we're closer together. Other years we're farther apart. There will be many opportunities before 2667 when we'll be almost as close as 2003.
  5. Jupiter's affect on Mars's orbit is negligible. Kepler calculated the motion of the planets quite accurately which Newton expanded on. Modern scientists today can very accurately predict the position and orbits of planets. And this is essentially common knowledge. Even basic astronomical software on personal computes and palmtops can calculate planets positions with a high degree of accuracy. If there was guesswork involved, we wouldn't be successfully launching probes into the solar system, using the gravity wells of Jupiter and Saturn to slingshot to more distant planets. We successfully drop probes onto other planets. Hello! Now, if they're talking about small distortions affecting Mars distance on the order of hundreds or thousands of kilometres, OK, that's possible. But... but... that will make little or no difference to us on Earth.
  6. The arc second calculations are, remarkably, mathematically, correct. For Aug 2003. But they are a tad too... detailed. Most people don't know what arc seconds means. That's like when they quote the air pressure in kilopascals; forecasters would be better off saying high and falling or low and rising. So, your pinky finger is about 1° wide, or 60 arc minutes wide, when held at arm's length. And that's 360 arc seconds!
  7. It is curious that there is a multiple line break before the line "Mars will look as large as the full moon to the naked eye." Ambiguous. Cindy treated this as a standalone sentence...
  8. The Mars rise times, again for 2003, are almost correct. It is true that around 3:00am, Mars reached its highest elevation in the sky, at the beginning of the month. The time is an hour early for the end of the month. But the gross error is that elevation is altitude not azimuth.
So, the bad news is, if you missed this (poorly written) email in the summer of 2003, you're going to have to wait over 600 years for an identical situation. If you're receiving this message now, you can delete it.

To see what you missed, review the 2003 Mars apparition notes. To see what's going on now and what will happen at the next interesting rendezvous, see the 2005 and 2007 notes.

OK. Now I'm tired. This "old" Mars email is filled big "cool" numbers, unusual terms (improperly used), and exaggerations. That it is resurfacing now is clearly an attempt to blindside people, to create a hullabaloo. And in that respect, I don't get it. Is the purpose of some spam email just to be forwarded, propagate like a wildfire, be instilled in other computers like memes? And to provoke elaborate, desperate responses (like mine)?!

I hope Cindy, Terry, Peter H, Peter C, Barbara, Malcolm, and maybe a few others will be better informed now and in the future.

Finally, I urge you all to halt this spam Mars email. Tell people "upstream" from you, the people who sent you the message, that it is spam or old. And strongly encourage them to tell their senders. And so on.

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