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Lesson Plans: Time that Star! (Day 2)

Stopwatch

Time That Star!

Day 2 Binary Star Data

Use the following data to perform Epoch Folding to determine the rotation period or the orbital period of the given sources.


Stellar Rotation Data

The following two data sets can tell astronomers how fast a star is rotating.

Cen X-3 Data

These data for Cen X-3 are rom EXOSAT satellite's Medium Energy experiment. All data are from 19 June 1985. The time is in seconds from the beginning of that day.

Time (Seconds) Rate (counts/cm2/s)
0 14.7062277
0.484 14.8695928
0.968 15.8992848
1.452 15.7533336
1.936 16.1208738
2.42 15.66
2.904 16.5468258
3.388 15.211294
3.872 15.5961072
4.356 15.3717151
4.84 14.7062277
5.324 14.8695928
5.808 15.8992848
6.292 15.7533336
6.776 16.1208738
7.26 16.5247452
7.744 16.5468258
8.228 5.211294
8.712 5.5961072
9.196 15.3717151

GX 301-2 Stellar Rotation Data

These data for GX 301-2 are from the A2 experiment aboard the HEAO-1 satellite. All data are from 1 February 1978. The time is in seconds from the beginning of that day.

Time (Seconds) Rate (counts/cm2/s) Time (Seconds) Rate (counts/cm2/s) Time (Seconds) Rate (counts/cm2/s)
72362.10 0.01388 73027.70 0.01953 73857.14 0.03258
72387.70 0.01512 73053.30 0.01688 73882.74 0.03518
72413.30 0.01593 73099.38 0.02005 73908.34 0.04642
72438.90 0.02347 73145.46 0.02447 73933.95 0.04945
72464.50 0.03103 73171.06 0.03435 73959.54 0.04190
72490.10 0.03113 73196.66 0.03123 73985.14 0.04512
72515.70 0.03387 73222.27 0.04637 74010.74 0.04933
72541.30 0.03270 73247.86 0.04983 74036.34 0.04593
72566.90 0.04195 73273.46 0.04498 74061.95 0.04435
72592.50 0.04873 73299.06 0.04375 74087.54 0.03997
72618.10 0.03942 73324.66 0.03735 74113.14 0.04358
72643.70 0.04453 73350.27 0.03998 74138.74 0.03462
72669.30 0.03557 73375.86 0.03278 74164.34 0.02330
72694.90 0.03318 73401.46 0.03377 74189.95 0.01715
72720.50 0.03347 73427.06 0.02837 74215.54 0.01945
72746.10 0.03520 73452.66 0.02468 74241.14 0.02760
72771.70 0.02420 73478.27 0.01903 74266.74 0.03603
72797.30 0.01890 73503.86 0.01927 74292.34 0.03190
72822.90 0.02057 73590.90 0.03228 74317.95 0.03705
72848.50 0.02873 73677.95 0.03677 74343.54 0.03342
72874.10 0.02737 73703.54 0.02440 74369.14 0.02537
72899.70 0.03315 73729.14 0.01590 74394.74 0.02307
72925.30 0.03692 73754.74 0.02042 74420.34 0.01768
72950.90 0.03377 73780.34 0.01408 74445.95 0.01930
72976.50 0.03375 73805.95 0.01908 74471.54 0.01730
73002.10 0.02500 73831.54 0.02345    

Orbital Data

The following two data sets can tell astronomers how fast two stars are orbiting each other.

Cir X-1 Orbital Data

These data for Cir X-1 are from the RXTE Satellite's All Sky Monitor. The time is the number of days from the beginning of the mission.

Time (Days) Rate (counts/s) Time (Days) Rate (counts/s) Time (Days) Rate (counts/s)
186.0 93.55 205.0 71.92 224.0 76.04
187.0 105.36 206.0 75.87 225.0 37.82
188.0 97.05 207.0 81.32 226.0 99.55
189.0 85.28 208.0 70.23 227.0 171.93
190.0 88.64 209.0 76.63 228.0 141.79
191.0 88.60 210.0 163.11 229.0 125.30
192.0 60.92 211.0 195.43 230.0 101.67
193.0 121.83 212.0 154.57 231.0 81.85
194.0 170.94 213.0 110.34 232.0 74.14
195.0 177.16 214.0 105.15 233.0 87.63
196.0 113.90 215.0 86.03 234.0 101.00
197.0 82.20 216.0 114.17 235.0 97.89
198.0 97.48 217.0 125.39 236.0 83.97
199.0 120.72 218.0 112.97 237.0 85.34
200.0 109.35 219.0 90.32 238.0 77.82
201.0 75.39 220.0 75.04 239.0 76.74
202.0 71.62 221.0 85.32 240.0 73.02
203.0 70.81 222.0 70.34 241.0 74.61
204.0 63.48 223.0 77.66    

GX 301-2 Orbital Data

These data for GX 301-2 are from the Vela 5B satellite. The time is the number of days from the beginning of the mission.

Time (Days) Rate (counts/s) Time (Days) Rate (counts/s)
41001.46 5.194 41087.55 4.008
41006.13 1.274 41092.22 0.407
41010.73 1.971 41096.88 0.522
41017.69 1.313 41103.66 0.164
41022.35 1.441 41107.27 0.187
41025.93 0.501 41113.02 0.173
41033.92 1.784 41117.71 0.302
41038.59 0.119 41122.36 10.349
41043.27 11.225 41127.03 1.128
41047.95 1.199 41132.80 0.478
41052.64 0.386 41137.50 0.786
41057.30 0.256 41143.28 1.999
41061.98 2.442 41147.95 1.843
41066.65 0.126 41152.64 1.605
41071.32 1.712 41157.27 0.304
41075.98 0.305 41161.96 5.784
41082.73 7.988 41166.64 5.509



 

A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

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