36 th International School for Young Astronomers 24 November – 12 December 2014 @ Chiang Mai, Thailand Photometric Observation
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
Photometric Observation
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
EXO-PLANET TRANSIT: PHOTOMETRIC OBSERVATION
Qian Shengbang, Yunnan Observatories
He Jiajia , Yunnan Observatories & National Astronomical Research Institute of Thailand
Maulidiani Az Zahra, Institut Teknologi Bandung
Eranga Thiina Jayashantha University of Kelaniya Sri Lanka
Grittiya Pongsupa Chiang Mai University
Nurul Fatini Jaafar, University of Science Malaysia
(Tutors)Prof Qian Shenbang
Dr He Jiajia
(Students)Eranga Thilina Jayashantha
Maulidiani Az ZahraGrittiya PongsupaNurul Fatini Jaafar
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
1.Introduction2.Objective
3.Observation4.Result and Analysis
5.Conclusions
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
If planet passes in front of parent star, the flux/luminosityof the star will temporarily drop drawing out a light curve
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
From period of the planet’s
orbit and period of the
transit occurred, diameter
of the planet’s orbit can be
measured.
The amount of starlight
blocked by the planet is
proportional to the cross-
sectional area of that
planet. Transit depth is
proportional to surface ratios
of planet and star. Planet
size relative to the star can
be measured.
2 types of planetary orbits in binary star system
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
SPX
X
• Learning on how to do photometricobservation
• Learning data reduction using IRAF software
• Learning on how to do data analysis to getminimum time, error and O-C diagram
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
• Telescope model: PlaneWave CDK24
• Aperture: 50 cm
• Focal length: 3962 mm
• Focal ratio: f/6.5
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
• ANDOR DW936N-#BV CCD
• Active pixels 2048 x 2048
• Sensor size 2.76 x 2.76 cm
• Pixel size (W x H) 13.5 μm x 13.5 μm
• Active area pixel well depth 100,000 e-
• Readout rate used 1 MHz
• Read noise 2.9 e-
• Temperature that we used -80°C (cooling by air)
• EQ 95% (BV)
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
No.Name of
TargetCoordinate
Observing Time(Local Time)
1TX CnC
RA:08h40m01.7sDEC:+18°59’59.5’’
01:43 – 02:50 a.m.
2 EH CNCRA:08h26m18.4sDEC:+20°52’50.0’’
02:58 – 04:15 a.m.
3 FG HyaRA:08h27m03.9sDEC:+03°30’52.3’’
04:38 – 06:00 a.m.
4 EQ TauRA:03h48m13.4sDEC:+22°18’51.0’’
09:40 – 10:40 p.m.
5 EE CetRA:02h49m52.3sDEC:+08°56’18.0’’
11:05p.m – 12:00 a.m.
• Observation date: 7 December 2014
• After midnight 7 December
• Before midnight 8 December
36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand
IRAF
1. Image reduction
2. Differential Photometry
3. Aperture Photometry
ORIGIN 70
1. Light Curve Fitting
2. Time of Minimum
3. O-C Diagram
No.Name of
TargetCoordinate
Observing Time(Local Time)
Minimum TimeHJD2456900+
1TX CnC
RA:08h40m01.7sDEC:+18°59’59.5’’
01:43 – 02:50 a.m.b-band :99,29855v-band: 99,29851
2 EH CNCRA:08h26m18.4sDEC:+20°52’50.0’’
02:58 – 04:15 a.m.b-band :99,35639
v-band: 99,356393
3 FG HyaRA:08h27m03.9sDEC:+03°30’52.3’’
04:38 – 06:00 a.m.-
4 EQ TauRA:03h48m13.4sDEC:+22°18’51.0’’
09:40 – 10:40 p.m.b-band :99,29855v-band: 99,29851
5 EE CetRA:02h49m52.3sDEC:+08°56’18.0’’
11:05p.m – 12:00 a.m.b-band :99,29855v-band: 99,29851