the spatiotemporal characteristics on the meteor action hsieh chun-min chen yu-ju

The Spatiotemporal Characteristics on the Meteor Action

HSIEH CHUN-MIN

CHEN YU-JU

Conclusion

Motive Equipment

Procedure

Discussion

MeteorMeteor

Motive

We have already known that when an object on earth does the vertical movement, its acceleration of gravity is “g”.  

How about meteors?  How about meteors?   Meteors enter the atmosphere because they are

attracted by the Earth's gravity, and what the movement patterns will they show?  

Does each meteor have a similar Does each meteor have a similar movement pattern? movement pattern?

Equipment

1. Meteor automatic observation camera(CCD) 2. Free Video to JPG Converter Software 3. UFO Analyzer Software 4. MS EXCEL software

Figure 1. Meteor automatic observation camera (CCD)

Procedure

UFO Analyzer1.Displacement2.Velocity

ZHR- time variation

Number-Mabs variation

Free Video to JPG Converter

Number-Velocity variation

Video camera(CCD)

Discussion 1

When we discuss the meteors exercise, we find the Perseids are not exercising with uniform accelerated motion as we predict and we speculate the result is related to the atmosphatmospheric resistanceeric resistance. The change of meteors’ sha shapepe may be one of the reasons why the instantaneous velocity is different. If the meteors’ shape isn’tn’t well-distributedwell-distributed, the meteors will have different speed because of the change of the torquetorque.

Discussion 2

The Perseids is the meteors from Perseids comet γ. The Meteoroid Environment Office of NASA points that the reason why the number of Perseids is much more than others may be that the Mother comet of Perseids is biggerbigger. The main reason why the number of Perseids is getting more is that the mother comet returreturnedned in 1990s and now the comet gets awaygets away, so the number of meteors is getting lessless every year.

Conclusions 1

The displacement and the average speed of the meteors shot at Taitung observatory (2012/8/13, AM 04:03) was 25.68 km and 33.35 km/s.

It matches the theory range(11~72 kms/s) It matches the theory range(11~72 kms/s) that the meteoroid enters the atmosphere.that the meteoroid enters the atmosphere.

It should be one of the groups of Perseus.It should be one of the groups of Perseus.

Conclusions 2

With the increase of the logarithmic value of time , the azimuth of meteor increases (y = 0.0005x + 2.2014, R2 = 0.9983), while the elevation decreases (y = -0.0091x + 1.4472, R2 = 0.9974).

Each of them has a significant linear Each of them has a significant linear relationshiprelationship (p <0.05).

The logarithmic variation of azimuth(az) and elevation(ev) of Taitung meteor observation

Conclusions 3

The logarithmic ratio of the azimuth to the time is about 1.7 (log az 1.7 log t az t1.7)The logarithmic ratio of the elevation to the time is about 1.0 (log ev 1.0 log t ev t1.0).

Conclusions 4

As time increases, the height of the meteor descends (y＝－ 1.6345x+111.19， R2=0.9992) ,but the instantaneous velocity shows irregirregular changesular changes.

At the height of 7979, which is in the range of ionosphere and mesosphere, the instantaneous velocity decreases obviously.

The variation between the height and instantaneous velocity

Conclusions 5

The peak period of perseids is on august 9. The closer the peak of the time, the more nu

mber of meteors can be seen . The ZHRmax is up to 6.

0

2

4

6

2013/7/250:00

2013/7/300:00

2013/8/40:00

2013/8/90:00

2013/8/140:00

2013/8/190:00

2013/8/240:00

2013/8/290:00

Time

ZH

R (

Zen

itha

l Hou

rly

Rat

e)

ZHR- time variation of Perseid

Conclusions 6

The patterns of magnitude and speed of 91 perseids show normal distributionsnormal distributions.

The peak of magnitude of meteors are between -2.5 and -2 and the peak of speed is between 58 and 60 km/s.

0

5

10

15

20

25

-6 -5 -4 -3 -2 -1 0 1Mabs

Num

bers

Number-Mabs variation of Perseids

0

5

10

15

20

25

36 42 48 54 60 66 72

Velocity (km/s)

Num

bers

Number-Velocity variation of Perseids

Reference of the study

C.L. Lin, Y. C. Wang, B. C. Chen and R. R. Shu, “Video Observation of Leonids 2001 in Taiwan”, 2005, CAST annual meeting.

Beech, Martin, 2006. Meteors and Meteorites. The Crowood Press.

http://www.tam.gov.tw