Expert: Tom Whiting - 11/22/2009

Question
I was looking into the north eastern sky at 6:30 p.m. and saw what I think may be a meteor.  It was unusually bright, appeared closer and more bright than any meteor i had ever seen.  It had a firey tail (at least 8 inches in perspective) and arced slowly downward the north, but did not fade, it went beyond the tree line and moved beyond my sight.  Do meteors have long tails and remain visible for more than 10 seconds?

Answer
Hi Jill,
Yes, they can and do. They can come in many varieties...no tail, no trail, long trails that instantly fade, or remain visible for many minutes, fast, slow, 1/10 of a second duration
or 10 seconds or even longer... dim, bright, exploding, fragmenting, non-fragmenting,
long paths, and pinpoint size bright spot (if they are coming right at you, called point
meteors). They can exhibit a multitude of colors from red to blue with yellow and
green (iron and copper) being dominant.

As far as the tree line, the meteor simply traveled over "your horizon" as most of them
do not impact the surface, even though it may look like it did...it probably didn't and just
went over your horizon.
As far as size and distance, the human eye can only detect brightness, not size or distance
for a single light source at night.  You can accurately say that it was, say, -4th magnitude
(as bright as Venus)...you can accurately say it subtended a 1/2 degree angle (size of full
moon in the sky) and you can accurately say that it passed from near the star Capella to the
bowl of the Big Dipper low in the north...but that's it.
The human eye cannot detect distance from a point like source (most burn up from 100-60 miles high on entry) nor can you determine it's actual size (most bright meteors are marble or walnut size).  (Regular meteors are grain of sand size.}  Regular meteor shower members are about the consistancy of cigarette ash.

If 3 or 4 observations are made widely separated, then you can triangulate and get a speed
and distance and possible track across the Earth, and perhaps an accurate impact point. But
it takes more than one observation.

Strangely, if it's not reported to the newspaper or local TV station, then it was just a
regular meteor. But if it makes enough attention to make the evening news, then it's a fireball.
If it explodes, it's called a bolide.
Meteors are only meteors while they give off light and heat thru the atmosphere; before that
they are meteoroids, and if they impact the surface, they become a meteorite. (Just a lesson
in terminology here).
You typically see a nice one like that about once per year if you do serious meteor watching.
Oh, we can also rule out that it came from the current meteor shower, the Leonids, because the
constellation Leo doesn't rise in the east until about midnight. So yours was a sporadic meteor,
one that comes in from any direction at any time. All Leonids come out of the east beginning
around midnight local time, until dawn.
Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA