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Posted on: METEOR SPLITTING IN TWO
at 10/07/2009 9:43am

Back in 1966 I saw a bright green meteor split in two pieces, asymmetrically, during the Perseids that summer. It was ... more(+)

Back in 1966 I saw a bright green meteor split in two pieces, asymmetrically, during the Perseids that summer. It was very low on the horizon, so that might have had some impact on the color. I saw another a few years later, and it was bright red, and almost overhead, another Perseid.

There is a website you can visit and report significantly bright meteors. Go to www.amsmeteor.org, and you will find it.

As to the sound, remember the meteor may have been more than 50 km. away, so the sound would have taken at least two and a half minutes to reach your location. It has, in fact, been documented that people (even the pros) think they hear a meteor as it passes, but, of course that cannot be (laws of physics, you know). People even report hearing the Aurora Borealis.

Finally, your finger width at arm length is closer to 2 degrees, so perhaps the meteor trail was longer than you thought.

All that aside, seeing bright meteors like that is an awesome event. Watch for them during the daylight, as well (I've seen one, and posted it on the website documented above).

Thanks for the post. close(-)

Posted on: Good view of a bolide meteor filmed by NASA
at 08/27/2009 10:25am

If you look at the frames posted by foundonmars, you'll note that the bolide comes into view just north (on the image, ... more(+)

If you look at the frames posted by foundonmars, you'll note that the bolide comes into view just north (on the image, it could be any compass direction) of a small bright area. If, at that time you extend the track of the object forward, you'll note that in each succeeding posted frame the track, although straight, migrates to the "northeast". This evidently is due to parallax, because the spacecraft is travelling to the "west" in the frames. This fact, and an estimate of angles and first-appearance altitudes, should allow those of you who are mathematically inclined, to estimate a velocity of the object (altitude of the shuttle should be obtainable from STS records). close(-)

Posted on: A question about de-orbiting
at 08/15/2009 8:34am

Not mentioned specifically in previous answers is why there are any heat loads at all. Well, every bit of the energy ... more(+)

Not mentioned specifically in previous answers is why there are any heat loads at all. Well, every bit of the energy it took to get the spacecraft into Earht orbit must be counteracted by the re-entry and landing technique. The cheapest way, in terms of fuel, is to let the atmosphere do the work. All the heat created during re-entry equates to all the energy used to get the spacecraft into orbit in the first place. Having said that, I'm wondering if that statement is just as true for multi-stage vehicles, winged vehicles, and SSTO vehicles. It would seem so, however (any comments?).

On a side note, according to a reference by Dr. von Braun, it is easier, in terms of fuel consumption, to get a spacecraft to, and land on, Mars than it is to do the same thing to and on the Moon. The reason is that Mars has a significant atmosphere to assist in both getting into an orbit around the planet and entering its atmosphere for a landing. The extra fuel to "escape" Earth is insignificant, because it isn't much more than the fuel used to just get to the vicinity of the moon. close(-)

Posted on: Fireball over Sussex, UK?
at 08/10/2009 5:38pm

Good evening.

You didn't say how far the object moved in the minute it was visible. However, the lack of a trail of ... more(+)

Good evening.

You didn't say how far the object moved in the minute it was visible. However, the lack of a trail of any sort, in my mind, wouldn't seem to be characteristic of an object re-entering the atmosphere (I've seen the space shuttle re-enter at night, and it leaves a trail). Could it have been a meterological ballon at high enough altitude that it was lit by the sun? Often such balloons will, when a certain altitude is reached, release the payload, which will then fall to Earth beneath a parachute. That payload would fall vertically, and perhaps get into darkness before any parachute opens. I don't know what they do to the main balloon, but it would make sense that, once the mission were over, the balloon would be deflated as quickly as possible.

There wasn't any unusual noise a few minutes later, was there? When the space shuttle re-enters, we hear a "sonic boom" even from our location in Louisiana, about 5 or 6 minutes after the shuttle passes us by. If there was such a noise (it wouldn't be real loud) then the above theory probably can be thrown in the garbage. close(-)

Commented on: Play 'Cosmic Slot Machine' and Help Astronomers
at 2009-11-25 09:18:01

This sounds like a slightly advanced version of the "Blink Comparator" used to find moving objects in astrophotographs. ... more(+)

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Commented on: Is Case Finally Closed on 1965 Pennsylvania 'UFO Mystery'?
at 2009-11-24 10:27:12

The Acorn shape is very reminiscent of later Soyuz re-entry modules. And, that would be about the time they would have ... more(+)

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Commented on: PETA Protests NASA Monkey Radiation Experiment
at 2009-11-20 07:30:09

Is PETA willing to settle all the lawsuits that will be filed if the astronauts return home seriously ill from ... more(+)

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Commented on: Cosmic Triple-Play: Asteroid Flyby, Fireball over Utah, Meteor Shower
at 2009-11-18 21:31:29

I think, SpaceJeff, that radar evidence would determine, very quickly, that the object was not an attack. Fifty years ... more(+)

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Commented on: Bubbling, Boiling Sun Photographed in Detail
at 2009-11-17 14:11:40

Coolstar, please read about the Little Ice Age. It lasted but a few years and was associated with nearly complete ... more(+)

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