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Re: (meteorobs) Astronomy magazine's coverage of the 2001 Leonids

Joe wrote:
        >>>  No . . . the BEST advice (at least for readers in North America)
would
>>>have been for Astronomy to indicate to their readers the predicted time when
>>>the encounter with the 1767 dust trail was predicted to take place (near or
>>>soon after 10 h UT on November 18).

   I have never understood why astronomy magazines can't just give their readers
event times in layman's terms.  Why can't they just say something like, "the peak
is expected around 5:00 AM EST Sunday *morning* on November 18th?"  They could
still give the UT times also.  Novices could easily be mislead by UT times and
even go out on the wrong night entirely!!!

Clear skies!
Kim Youmans

"Joe Rao (via Lew Gramer)" wrote:

> >To: meteorobs@atmob.org, astro-l@uwwvax.uwwdot edu
> >Cc: imo-news@yahoogroups.com, atmob-discuss@atmob.org, [...]
>
> Just picked up a copy of the November 2001 issue of Astronomy magazine.
> Regarding the information they provide to their readers concerning the
> upcoming Leonid meteor shower, writers Martin Radcliffe and Alister Ling
> note the following:
>
> On page 70:
>
> "A fury of falling stars will shoot across the heavens, the likes of which
> have not been witnessed since the 1966 Leonid meteor shower."
>
>     Not exactly true . . . the 1966 shower briefly produced visual hourly
> rates of perhaps 150,000.  At their best in 2001, the Leonid predicted rates
> a full order of magnitude lower (~15,000/hr).
>
> "The storm surge is expected to hit at night for Australasia and reserve a
> good squall for the Western Hemisphere a few hours later."
>
>     Wrong! The Western Hemisphere is anticipated to see enhanced Leonid
> activity before the Far East.  Peak activity for the Western Hemisphere is
> due near, or soon after 10 h UT on November 18, while Australasia should see
> their outburst roughly eight hours later.
>
> "Meteor counts are likely to range from a couple of hundred per hour over the
> Americas to a few thousand per hour on the other side of the world."
>
>     Even the most conservative estimates indicate hourly rates of at least
> 1000/hr. over the Americas, with anywhere from 5000 to 15,000/hr. possible
> for parts of Asia and Australia.  This statement also contradicts what was
> written in the first paragraph ("A fury of falling stars will shoot across
> the heavens, the likes of which have not been witnessed since the 1966 Leonid
> meteor shower").  How can one initially draw comparisons to such a stupendous
> display as the 1966 Leonids by later suggesting hourly rates of ". . . a
> couple of hundred to a few thousand" for the 2001 Leonids?
>
> On page 78:
>
> "A pair of astronomers from the Armagh Observatory in Northern Ireland
> correctly predicted the great Leonid meteor show in 1999 and the lack of a
> great display in 2000."
>
>     While their names are nowhere mentioned in the Astronomy article, this is
> no doubt an allusion to David Asher and Rob McNaught.  However, while Asher
> is indeed affiliated with Armagh Observatory,  McNaught resides in Australia
> and is affiliated with the Australian National Observatory and Siding Spring
> Observatory.
>
> "The storm, if it does occur, will result from Earth passing through streams
> of locally dense meteoric debris during the early hours of November 18.  The
> two streams were deposited along the orbit of the parent comet Swift-Tuttle
> in 1699 and 1866."
>
>     Actually, the storm resulting from these two dust trails will be
> available only from eastern Asia and Australia . . . and since these regions
> are to the west of the International Date Line, the correct time of encounter
> should be ". . . during the early hours of November 19."
>
> "Because meteor shower prediction is in its infancy, the potential for
> disappointment is considerable."
>
>     This almost sounds like something that was written in advance a 1960s
> Leonid shower.  In sharp contrast, recent predictions of meteor outbursts
> using the new dust-trail methodology (pioneered in Russia and later refined
> by reputable meteor scientists in other parts of the world) have proven to be
> very reliable in anticipating unusually high activity and even more accurate
> in predicted times of such outbursts.
>
> "The best advice is to keep a careful watch on the skies from midnight until
> dawn on November 18."
>
>     No . . . the BEST advice (at least for readers in North America) would
> have been for Astronomy to indicate to their readers the predicted time when
> the encounter with the 1767 dust trail was predicted to take place (near or
> soon after 10 h UT on November 18).
>
>     Unfortunately, because their readership was not provided with this very
> important piece of information.  I can envision many neophyte observers
> dutifully heading out at the stroke of midnight, yet ironically calling it a
> night after an hour or two in the cold only because they weren't seeing the
> hoped-for meteor storm . . . only to wake up later that morning to hear that
> the anticipated "good squall" did indeed occurred but only after they had
> reacquainted themselves with their nice warm beds!
>
> Joe Rao
>
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