Kaedah pengesanan planet luar sistem suria: Perbezaan antara semakan
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[[Image:Exoplanet Period-Mass Scatter Discovery Method TR.png|thumb|300px|right|Sifat (jisim dan paksi separautama) bagi planet yang dijumpai menggunakan kaedah transit, berbanding (kelabu pucat) dengan planet dijumpai dengan menggunakan kaedah yang lain.]]
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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>▼
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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.▼
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Tambahan lagi, gerhana kedua (apabila planet dihalang oleh bintangnya) membenarkan ukuran langsung bagi radiasi planet. 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.
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