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Kaedah pengesanan planet luar sistem suria: Perbezaan antara semakan

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|arxiv = astro-ph/0501269 }}</ref> sungguhpun ia tidak menjawab persoalan samaada sebarang planet tertentu merupakan hos kepada planet.
 
Keduanya, kaedah ini memiliki kadar pengesanan palsu yang tinggi. Pengesanan lintasan memerlukan pengesahan tambahan, biasanya dari kaedah hadlaju-jejarian.<ref>{{cite journal | author=O'Donovan ''et al.'' |
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Secondly, the method suffers from a high rate of false detections. A transit detection requires additional confirmation, typically from the radial-velocity method.<ref>{{cite journal | author=O'Donovan ''et al.'' |
title=Rejecting Astrophysical False Positives from the TrES Transiting Planet Survey: The Example of GSC 03885-00829 | journal=The Astrophysical Journal | year=2006 | volume=644 | issue=2 | pages=1237–1245 | url=http://www.iop.org/EJ/article/0004-637X/644/2/1237/64043.html |
doi=10.1086/503740 | last2=Charbonneau | first2=David | last3=Torres | first3=Guillermo | last4=Mandushev | first4=Georgi | last5=Dunham | first5=Edward W. | last6=Latham | first6=David W. | last7=Alonso | first7=Roi | last8=Brown | first8=Timothy M. | last9=Esquerdo | first9=Gilbert A. | bibcode=2006ApJ...644.1237O|arxiv = astro-ph/0603005 }}</ref>
 
[[Image:Exoplanet Period-Mass Scatter Discovery Method TR.png|thumb|300px|right|PropertiesSifat (massjisim anddan semimajorpaksi axisseparautama) ofbagi planetsplanet discoveredyang usingdijumpai themenggunakan transitkaedah methodtransit, comparedberbanding (lightkelabu graypucat) withdengan planet dijumpai planetsdengan discoveredmenggunakan usingkaedah otheryang methodslain.]]
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The main advantage of the transit method is that the size of the planet can be determined from the lightcurve. When combined with the radial velocity method (which determines the planet's mass) one can determine the density of the planet, and hence learn something about the planet's physical structure. The nine planets that have been studied by both methods are by far the best-characterized of all known exoplanets.<ref name="charbonneautransitreview">{{cite conference | first=D. | last=Charbonneau | coauthors=T. Brown; A. Burrows; G. Laughlin | title=When Extrasolar Planets Transit Their Parent Stars | booktitle=Protostars and Planets V | publisher=University of Arizona Press | year=2006 | arxiv=astro-ph/0603376}}</ref>
 
kaedah transit turut membolehkan pengkajian mengenai atmosfera planet yang melintas. Apabila planet merentasi bintang, cahaya dari bintang melepasi bahagian atas atmosfera planet. Dengan mengkaji spektrum stelar beresolusi tinggi dengan teliti, seseorang mampu mengesan unsur yang hadir pada atmosfera planet. Atmosfera sesebuah planet (dan planet itu sendiri) juga boleh dikesan dengan mengukur pengkutuban cahaya bintang ketika ia melalui atau dibiaskan oleh atmosfera planet.
The transit method also makes it possible to study the atmosphere of the transiting planet. When the planet transits the star, light from the star passes through the upper atmosphere of the planet. By studying the high-resolution stellar spectrum carefully, one can detect elements present in the planet's atmosphere. A planetary atmosphere (and planet for that matter) could also be detected by measuring the polarisation of the starlight as it passed through or is reflected off the planet's atmosphere.
 
AdditionallyTambahan lagi, thegerhana secondary eclipsekedua (when theapabila planet isdihalang blockedoleh by its starbintangnya) allowsmembenarkan directukuran measurementlangsung ofbagi theradiasi planet's radiation. If the star's [[photometry (astronomy)|photometric]] intensity during the secondary eclipse is subtracted from its intensity before or after, only the signal caused by the planet remains. It is then possible to measure the planet's temperature and even to detect possible signs of cloud formations on it. In March 2005, two groups of scientists carried out measurements using this technique with the [[Spitzer Space Telescope]]. The two teams, from the [[Harvard-Smithsonian Center for Astrophysics]], led by [[David Charbonneau]], and the [[Goddard Space Flight Center]], led by L. D. Deming, studied the planets [[TrES-1]] and [[HD 209458b]] respectively. The measurements revealed the planets' temperatures: 1,060 [[Kelvin|K]] (790°[[Celsius|C]]) for TrES-1 and about 1,130 K (860°C) for HD 209458b.
<ref>{{cite journal | author=Charbonneau ''et al.'' | title=Detection of Thermal Emission from an Extrasolar Planet | journal=The [[Astrophysical Journal]] | year=2005 | volume=626 | issue=1 | pages=523–529 | url=http://www.iop.org/EJ/article/0004-637X/626/1/523/62152.html | doi=10.1086/429991 | last2=Allen | first2=Lori E. | last3=Megeath | first3=S. Thomas | last4=Torres | first4=Guillermo | last5=Alonso | first5=Roi | last6=Brown | first6=Timothy M. | last7=Gilliland | first7=Ronald L. | last8=Latham | first8=David W. | last9=Mandushev | first9=Georgi | bibcode=2005ApJ...626..523C|arxiv = astro-ph/0503457 }}</ref><ref name="Deming">
{{cite journal | author=Deming, D.; Seager, S.; Richardson, J.; Harrington, J. | title=Infrared radiation from an extrasolar planet | journal=Nature | year=2005 | volume=434 | issue= 7034| pages=740–743 | url=http://www.obspm.fr/encycl/papers/nature03507.pdf | doi=10.1038/nature03507|format=PDF | pmid=15785769|arxiv = astro-ph/0503554 |bibcode = 2005Natur.434..740D }}</ref> In addition the hot Neptune [[Gliese 436 b]] enters secondary eclipse. However some transiting planets orbit such that they do not enter secondary eclipse relative to Earth; [[HD 17156 b]] is over 90% likely to be one of the latter.
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