Taxonomy of the Extrasolar Planet

Abstract

When a star is described as a spectral class G2V, we know that the star is similar to our Sun. We know its approximate mass, temperature, age, and size. When working with an extrasolar planet database, it is very useful to have a taxonomy scale (classification) such as, for example, the Harvard classification for stars. The taxonomy has to be easily interpreted and present the most relevant information about extrasolar planets. I propose an extrasolar planet taxonomy scale with four parameters. The first parameter concerns the mass of an extrasolar planet in the form of units of the mass of other known planets, where M represents the mass of Mercury, E that of Earth, N Neptune, and J Jupiter. The second parameter is the planet's distance from its parent star (semimajor axis) described in a logarithm with base 10. The third parameter is the mean Dyson temperature of the extrasolar planet, for which I established four main temperature classes: F represents the Freezing class, W the Water class, G the Gaseous class, and R the Roasters class. I devised one additional class, however: P, the Pulsar class, which concerns extrasolar planets orbiting pulsar stars. The fourth parameter is eccentricity. If the attributes of the surface of the extrasolar planet are known, we are able to establish this additional parameter where t represents a terrestrial planet, g a gaseous planet, and i an ice planet. According to this taxonomy scale, for example, Earth is 1E0W0t, Neptune is 1N1.5F0i, and extrasolar planet 55 Cnc e is 9E-1.8R1. Key Words: Catalogues—Extrasolar planet—Habitable zone—Planets. Astrobiology 12, 361–369.

1. Introduction

A stronomical papers, for the most part, specify the spectral type of stars in the first reference according to the Harvard spectral classification. When this information is known, the effective temperature of the star, its color, mass, and radius can be roughly estimated. Unfortunately, a taxonomy scale for extrasolar planets (EPs) similar to the Harvard classification for stars does not exist. We know of more than 700 EPs (as of December 2011). Moreover, Borucki et al. (2011) nominated more than 1200 candidates for EPs from analysis of only the first 4 months' data. It would be helpful to investigators if a simple and comprehensive taxonomy were available when working with a large number of EPs. Some labeling for EPs has been implemented; close-in planets, for example, have been identified and so labeled, as have giant planets, jovian planets, hot Jupiters, hot planets, Neptune-mass planets, Saturn-mass planets, rocky planets, and super-Earths. This labeling has contributed to the development of our knowledge of EPs and enabled investigators to identify different types of EPs simultaneously. However, a label such as “Neptune-mass planet” could refer to a close-in planet or to an ice planet. Other, more precise identification labels have entered into the lexicon, such as a close-in terrestrial planet (Haghighipour and Rastegar, 2011), but by and large a general taxonomy for EPs is yet to be established.

There are three different taxonomies in astronomy. The first was proposed by Sudarsky, Burrows, and Hubeny (2003); the second was created by Marchi (2007); and a third taxonomy was projected by Lundock et al. (2009). All these taxonomies have a benchmark in the spectrum of EPs. These are very precise taxonomies, but the initial quick data about an EP is very complicated and does not indicate the main features of EPs. Here, it is proposed that taxonomy data of a particular EP should be easily comparable to that of others.

2. Taxonomy

To establish the general features of the EP, it is requisite that, at the very least, the planet's mass and semimajor axis are known. It is helpful if the eccentricity, temperature characteristics, period, radius, and density are known as well. The seven parameters mentioned here, however, are too numerous and involved to be included in a comprehensible and comparable taxonomy. Temperature is the only parameter used in the Harvard classification. A star's mass, however, which is closely related to its temperature, is the most important condition for its evolution. For this reason, only one parameter in a star's classification is necessary. Today's research indicates that, for EPs, more than one parameter for their evolution is needed.

I endeavored to choose the most important features of EPs as parameters for the proposed taxonomy. I selected the following five parameters: mass, semimajor axis, mean Dyson temperature, eccentricity, and surface attributes.

2.1. Mass of the extrasolar planet

It is thought that the most important parameter of an EP is its mass. The first parameter of the taxonomy is information that concerns the mass of an EP. The mass of Jupiter is currently used as a benchmark mass unit for EPs. It is assumed that many more EPs will be discovered with masses less than that of Earth and possibly less than that of Mercury. I have established units of the mass of some known planets in the Solar System. For EPs with a mass less than 0.003 M _Jup, I established the mass unit of Mercury (3.302×10²³ kg). We are aware of EPs with a mass in this category. For EPs with a mass between 0.003 and 0.05 M _Jup, I established a mass unit scale of Earth (5.9736×10²⁴ kg). There are at least 10 known EPs with a mass in this category. The group of EPs known as super-Earths are members of this mass unit. For EPs with a mass between 0.05 and 0.99 M _Jup, I established a mass unit scale of Neptune (1.0243×10²⁶ kg). Of these EPs there are quite a large number—more than a hundred. For EPs with a mass more than 1 M _Jup, I used the mass unit scale of Jupiter (1.8986×10²⁷ kg). In this category are currently the largest numbers of EPs.

The form of this parameter in the taxonomy is the integer number of the mass unit and the first letter of the planet it corresponds to, where M represents Mercury, E Earth, N Neptune, and J Jupiter. For example, Earth is 1E, Neptune is 1N, Uranus 15E, and 55 Cnc e 9E.

2.2. Semimajor axis

The position of an EP in its stellar system is the next very important parameter that influences many other features of this celestial body. For this reason, the second parameter of the taxonomy is the distance between the EP and its parent star in astronomical units.

Initially, I had hoped to define this parameter in two different ways: one for a semimajor axis less than 1 AU different and another for a semimajor axis greater than 1 AU. For a semimajor axis less than 1 AU, I wanted to use a decimal number with one decimal position; for a semimajor axis less than 0.1 AU, I wanted to use a decimal number with two decimal positions. For a semimajor axis greater than 1 AU, I wanted to use an integer number. However, it became clear that this method would result in a complicated and unclear outcome.

In the end, I chose to define the second parameter in logarithm form1. I used a logarithm with base 10 from a semimajor axis and rounded the calculated value to the nearest decimal point. For EPs with a semimajor axis smaller than 1 AU, this parameter is negative, and with the decreasing value of a semimajor axis, the value of this parameter rapidly decreases to −2. Values smaller than −2 (semimajor axis is 0.01), at present, are unexpected. For the value of a semimajor axis equal to 1 AU, the value of this parameter is 0. For a semimajor axis with a value greater than 1, the value of this parameter is positive. For example, the value of a semimajor axis equal to 10 AU has a parameter value of 1, and for a semimajor axis with a value of 100 AU, this parameter is 2.

For example, for Earth this parameter has the form of 0, for Neptune the form is 1.5, Uranus 1.3, 55 Cnc c −0.6 (the semimajor axis is 0.2403 AU), and 55 Cnc e is −1.8 (the semimajor axis is 0.0156 AU).

2.3. Mean Dyson temperature

The value of the surface temperature of an EP depends on many parameters, for example, albedo, speed of the rotation of the EP, or the structure of its atmosphere. A precise temperature value of an EP cannot be determined from observable data. It was necessary to establish a new universal parameter for temperature in the taxonomy, which could be determined for most known EPs.

By using the Stefan-Boltzmann law, the flux on the surface of a parent star can be expressed as \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}L = 4 \pi R_*^2 T_*^4 \zeta \tag{1}\end{align*} \end{document}

where R* is the radius of the star, T* the effective temperature of the star, and ζ the Stefan-Boltzmann constant. An effective radiating temperature for a planet, which is rotating slowly, can be calculated by the following equation (e.g., Karttunen et al., 2003): \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}T = T_* \left( \frac { 1 - A } { 2 } \right) ^ { 1 / 4 } \left( \frac { R_* } { R_ { \rm EP } } \right) ^ { 1 / 2 } \tag { 2 } \end{align*} \end{document}

Here, R _EP is the distance from the parent star to the EP, and A is Bond albedo of the planet. An effective radiating temperature for a planet that is rotating quickly is \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}T = T_* \left( \frac { 1 - A } { 4 } \right) ^ { 1 / 4 } \left( \frac { R_* } { R_ { \rm EP } } \right) ^ { 1 / 2 } \tag { 3 } \end{align*} \end{document}

For the EP, it can generally be said that the planet orbits quickly, and the temperature can be calculated by Eq. 3. Even so, it is possible that close-in planets with a very short period have a synchronous rotation, and Eq. 2 must be used as opposed to Eq. 3. This ambiguous fact leads to the establishment of a new parameter: the Dyson temperature. It is a temperature that has an artificial sphere the size of a planetary orbit (Dyson sphere) (Dyson, 1960), which can be defined according to the following equation. \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}T_ { \rm EP } ^4 = \frac { T_*^4 R_*^2 } { R_ { \rm EP } ^2 } \tag { 4 } \end{align*} \end{document}

For an EP with a small value of eccentricity, Eq. 4 can be used directly. However, in the case when an EP has a large value of eccentricity, the distance from the parent star changes, according to the Second Keplerian law, without homogeneity and in many cases rapidly. In some cases, the Dyson temperature changes very rapidly, too. For better precision of the calculation of the Dyson temperature, I divided the EP's orbit into 10 equal segments, according to the time needed for a complete rotation. For this calculation, I used the Kepler equation. For the calculation of the eccentric anomaly, I used an iteration method with three steps (see, e.g., Andrle, 1971) and calculated the value of the momentary distance of an EP from its parent star, using the following equation (see, e.g., Karttunen et al., 2003): \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}R_{ \rm EP} = a ( 1 - e \cos E ) \tag{5}\end{align*} \end{document}

Here, a is the semimajor axis, e the eccentricity, and E the eccentric anomaly of an EP. I used this value of distance in Eq. 4 and calculated the momentary Dyson temperature. I calculated the Dyson temperature for 10 equal segments, according to the second Keplerian law; and from these 10 values I calculated the arithmetical mean, which I defined as the mean Dyson temperature (t _EP ) for the EP.

For EPs for which the value of their albedo and speed of rotation are known, their effective radiating temperature can be calculated by \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}T = \left( \frac { 1 - A } { 2 } \right) ^ { 1 / 4 } t_ { \rm EP } \tag { 6 } \end{align*} \end{document}

for planets with a slow rotation, and by \documentclass{aastex}\usepackage{amsbsy}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{bm}\usepackage{mathrsfs}\usepackage{pifont}\usepackage{stmaryrd}\usepackage{textcomp}\usepackage{portland, xspace}\usepackage{amsmath, amsxtra}\pagestyle{empty}\DeclareMathSizes{10}{9}{7}{6}\begin{document} \begin{align*}T = \left( \frac { 1 - A } { 4 } \right) ^ { 1 / 4 } t_ { \rm EP } \tag { 7 } \end{align*} \end{document}

for planets with a quick rotation.

For example, the mean Dyson temperature of Earth is 392 K, and the albedo is 0.3. With Eq. 7, the effective radiating temperature is 254 K.

For a clearer differentiation, I established four main temperature classes. The coldest class is the Freezing class, which is indicated as F. The members of this class have a mean Dyson temperature less than 250 K. Jupiter, Saturn, Neptune, and Uranus are members of this class. The second class is the Water class, and it is indicated as W. Members of this class have a mean Dyson temperature that ranges from 250 to 450 K. An EP from this class could have liquid water at its surface. Earth and Mars are members of this class. For the third class, the mean Dyson temperature ranges from 450 to 1000 K. This is termed the Gaseous class and is indicated as G. Mercury and Venus are members of this class. And finally, the fourth class is the hottest class and is comprised of planets with a mean Dyson temperature higher than 1000 K. This class is aptly named the Roasters class, and it is indicated as R. Many of the members of this class are called close-in planets.

I defined the Water class as planets that reside in the habitable zone (HZ), as defined by Kasting, Whitmire, and Reynolds (1993). These authors purported conservative estimates of HZ boundaries to be 0.95 AU for the inner edge closest to the Sun and 1.37 AU for the outer edge. It should be noted that Michna et al. (2000) calculated that the outer boundary could be at distances as great as 2.4 AU, and Dole (1970) marked the inner boundaries as 0.725 AU. I used the “optimistic” boundaries 0.725 and 2.4 AU for the definition of the Water class. The value of the mean Dyson temperature for a hypothetical planet with the same parameter as Earth and an orbit with a semimajor axis of 0.725 AU is 460 K. This value for a hypothetical planet with the same parameter as Earth, but with a=2.4 AU, is 253 K. Considering the fact that the boundaries of the HZ are not expressly defined, I established the range of the mean Dyson temperature for the Water class to be 250–450 K.

It is known that some EPs orbit pulsar stars. For such EPs, I predicted that their behavior would be totally different than that of EPs that orbit stars in the main sequence. I could not calculate the mean Dyson temperature of these EPs and so created an additional class, named the Pulsar class, which is indicated as P.

2.4. Eccentricity

As shown in the previous paragraph, the eccentricity of an EP is the next very important behavioral characteristic, which I included in the taxonomy as the fourth parameter. For easier reference, I used only the first decimal position for the value of eccentricity, which is rounded.

2.5. Surface attribute

Generally speaking, an EP's surface characteristics cannot be defined; however, an improvement of observational equipment would allow for better and more precise data and specification of surface characteristics for many EPs in the future. For this reason, I considered a fifth additional parameter in the taxonomy: the surface attribute.

I considered three different surface attributes, according to the type of surfaces that have been observed in the Solar System. The first surface attribute is a terrestrial-like planet surface. Mercury, Venus, Mars, and of course Earth have terrestrial-like planet surfaces, and this attribute is indicated as a lowercase t. The second surface attribute is a gaseous planet surface, such as that of Jupiter or Saturn. I indicated this attribute with a lowercase g. The third surface attribute is an ice planet surface similar to that of Uranus or Neptune. This attribute is indicated as a lowercase i.

It is assumed that, as we begin to detect EPs with a mean Dyson temperature above or below that found in the Solar System, more and more EPs will emerge with different surface attributes, which will have to be defined. The possibilities are endless and may include, for example, surfaces of ocean water or magma. This is unheard of at our present level of understanding.

3. Interpretation Examples

With all the necessary parameters defined, I considered a structure for the taxonomy. Below, I present my proposed taxonomy with a sample planet from the Solar System, Venus.

The taxonomy class for Venus is 15M-0.1G0t.

That is,

15 M: The mass of Venus is 15 times greater than the mass of Mercury. Precisely put, the mass of Venus is 4.8685×10²⁴ kg, roughly 15 times more than the mass of Mercury.

−0.1: Venus's semimajor axis is 0.723 AU. The logarithm with base 10 from this value is −0.1.

G: The mean Dyson temperature is between 450 and 1000 K. The exact Dyson orbit temperature is 461 K.

0: Venus is orbiting on a near-circular orbit with an eccentricity value of 0.0068.

t: Venus has a solid surface, which we can say is a terrestrial-like planet surface.

The taxonomy class for the first discovered extrasolar planet orbiting a main sequence star 51 Peg b is 9N-1.3R0. That is,

9N: The mass of 51Peg b is 0.468 M _Jup, which is 8.67 M _Nep (mass of Neptune).

−1.3: The b semimajor axis of 51 Peg b is 0.052 AU. The logarithm with base 10 from this value is −1.3.

R: The mean Dyson temperature is higher than 1000 K; more precisely, it is 1938.6 K.

0: The EP 51 Peg b is orbiting on a circular or near-circular orbit. The value is precisely 0.

The surface attribute parameter is mentioned only in the case when we can specify it.

The method of taxonomy as schematically explained is in Fig. 1.

FIG. 1.

Schematic explanation—a definition of the taxonomy of the EPs for which we are able to determine the taxonomy scale.

4. Practical Examples

When working with large groups of EPs, it is practically impossible to compare them by using an easy and quick mechanism. For example, there are five EPs in the planetary system 55 Cnc. Without quite a wide table, it is impossible to say which EP is the smallest, which has the farthest or the closest orbit, or which planet has the most eccentric orbit, and so on. Using the proposed taxonomy, one can answer these questions practically immediately. For example, the closest planet is 55 Cnc e, with a semimajor axis of about 0.02 AU (exactly written 0.0156 AU). We can immediately say that the value of the eccentricity for 55 Cnc c and for 55 Cnc e is nearly the same (the exact eccentricity for 55 Cnc c is 0.053, and the eccentricity for 55 Cnc e is 0.057). The data and taxonomy identification regarding EP members of the system 55 Cnc are in Table 1.

Table 1.

Five EPs in System 55 Cnc (HD75732)

Name	55 Cnc b	55 Cnc c	55 Cnc d	55 Cnc e	55 Cnc f
Taxonomy	15N-0.9R0	3N-0.6G1	4J0.8F0	9E-1.8R1	3N-0.1W0
Mass (M _Jup)	0.824	0.169	3.835	0.027	0.144
Semimajor axis (AU)	0.1148	0.2403	5.76	0.0156	0.781
Logarithm from semimajor axis	−0.94	−0.62	0.76	−1.81	−0.11
Mean Dyson temperature (K)	1010.0	698.0	142.6	2739.4	387.2
Eccentricity	0.0159	0.053	0.025	0.057	0.0002
Period (days)	14.651262	44.3446	5218	0.73654	260.7

The application of this taxonomy for EPs with a different parent star is quite significant. For example, we can compare EPs that host one of the members of the binary stellar systems. We know more than 60 systems with such a condition. The data for several EPs orbiting one of the stars in a binary stellar system are in Table 2. We only need the first line of the table to say which EP from this group is the heaviest (70 Vir b), which one is the hottest (tau Boo b), or which has the most distant orbit (eps Eridani Ac), along with many other features.

Table 2.

Name	70 Vir b	eps Eridani Ab	eps Eridani Ac (unconfirmed)	gamma Cephei b (HD 222404)	HD 142Ab	tau Boo b (HD 120136 b)
Taxonomy	7J-0.3G4	2J0.5F7	2N1.6F3	2J0.3G0	1J0W4	4J-1.3R0
Planet mass (M _Jup)	6.6	1.55	0.1	1.85	1.03	3.9
Semimajor axis (AU)	0.48	3.39	40	2.05	1	0.046
Logarithm from semimajor axis	−0.32	0.53	1.60	0.31	0.0	−1.34
Mean Dyson temperature (K)	737.1	51.6	174.8	503.2	385.3	2301.7
Eccentricity	0.43	0.702	0.3	0.040	0.37	0.018
Period (days)	116.67	2502	102270	903.3	339	3.3135
Spectral class parent star	G4V	K2V	K2V	K2V	G1 IV	F7V
Mother star mass (M _Sun)	0.92	0.83	0.83	1.4	1.1	1.3
T _Eff parent star (K)	5432	5116	5116	4800	6180	6309
Radius parent star (R _Sun)	1.968	0.895	0.895	4.9	0.86	1.331

The data and taxonomy identification for a few example EPs are shown in Table 3 (see Appendix), and the taxonomy identification for other known EPs that we can classify are in Table 4 (see Appendix).

5. Conclusion

I have endeavored to build a taxonomy scale for EPs that, first, could be used as a quick and easy mechanism to determine the main attributes for an EP and, second, could allow for a quick and clear comparison of large numbers of EPs. The taxonomy scale of EPs for which we know the values for mass, semimajor axis, and eccentricity can be determined along with the values for the radius and effective temperature of their parent stars. Almost 500 known EPs have been found with this condition. For rapid determination and understanding of the taxonomy of an EP, a graphic guide is shown in Fig. 1 in which the method purported here for defining the taxonomy identification of an EP is schematically interpreted.

Footnotes

Acknowledgments

I am grateful to Y. Dutil and anonymous referees for their informative comments and suggestions that helped to improve the content.

Abbreviations

EP, extrasolar planet; HZ, habitable zone.

Appendix

Table 4.

Taxonomy Identification for Known EPs (Except EPs That Are in Table 3)

Planet	Taxonomy	Planet	Taxonomy	Planet	Taxonomy	Planet	Taxonomy
11 Com b	19J0.1R2	GJ 581 b	16E-1.4G0	HD 109246 b	14N-0.5G1	HD 160691 e	2J0.7F1
11 UMi b	11J0.2R1	GJ 581 e	2E-1.6G3	HD 110014 b	11J0.3G5	HD 16141 b	4N-0.5G4
14 And b	5J-0.1R8	GJ 581 c	5E-1.1G1	HD 113538 b	0N-0.1W6	HD 16175 b	4J0.3W6
14 Her b	0J0.4F4	GJ 581 d	6E-0.7W3	HD 113538 c	1N0.4F3	HD 162020 b	14J-1.1R3
16 Cyg B b	2J0.2W7	Gl 179	15N0.4F2	HD 114386 b	1J0.2F2	HD 163607 b	14N-0.4G7
18 Del A b	10J0.4G1	Gl 86 b	4J-1G0	HD 114729 A b	16N0.3W3	HD 163607 c	2J0.4W1
25 Sec c	16N0.3G3	Gliese 876 c	15N-0.9W3	HD 114762 A b	11J-0.5G3	HD 165409 b	9N-0.1W3
24 Sec b	2J0.1G1	Gliese 876 b	2J-0.7W0	HD 114783 b	1J0.1W1	HD 164922 b	7N0.3F1
30 Ari Bb	10J0G3	Gliese 876 d	7E-1.7G2	HD 11506 c	15N-0.2G4	HD 167042 b	2J0.1G0
4 Uma b	7J-0.1R4	Gliese 876 e	9N-0.5F1	HD 11506 b	3J0.4W2	HD 168443 c	17J0.5W2
42 Dra b	3J0.1R4	HAT-P-1 b	10N-1.3R1	HD 116029 b	2J0.2G2	HD 168443 b	8J-0.5G5
47 Uma c	10N0.6F1	HAT-P-11 b	26E-1.3R2	HD 117207 b	2J0.6F2	HD 168746 b	4N-1.2R1
47 Uma d	2J1.1F2	HAT-P-12 b	4N-1.4R0	HD 117618 b	3N-0.8R4	HD 1690 b	6J0.1R6
47 Uma b	3J0.3W0	HAT-P-13 c	15J0.1W7	HD 11964 b	12N0.5W0	HD 169830 b	3J-0.1G3
51 Peg b	9N-1.3R0	HAT-P-13 b	16N-1.4R0	HD 11964 c	25E-0.6R3	HD 169830 c	4J0.6W3
55 Cnc A b	15N-0.9R0	HAT-P-14 b	2J-1.2R1	HD 11977 b	7J0.3G4	HD 170469 b	12N0.4W1
55 Cnc A f	3N-0.1W0	HAT-P-15 b	2J-1R2	HD 121504 b	1J-0.5G0	HD 171028 b	2J0.1G6
55 Cnc A c	3N-0.6G1	HAT-P-16 b	4J-1.4R0	HD 122430 b	4J0R7	HD 17156 b	3J-0.8R7
55 Cnc A d	4J0.8F0	HAT-P-17 b	10N-1.1R3	HD 125612A c	18E-1.3R3	HD 173416 b	3J0.1R2
55 Cnc A e	9E-1.8R1	HAT-P-17 c	1J0.4F1	HD 125612A b	3J0.1W5	HD 175541 b	11N0G3
6 Lyn b	2J0.3G1	HAT-P-18 b	4N-1.3R1	HD 125612A d	7J0.6F3	HD 177830 b	1J0.1G0
61 Vir c	18E-0.7G1	HAT-P-19 b	5N-1.3R1	HD 12661 b	2J-0.1W4	HD 177830 c	3N-0.3G3
61 Vir d	23E-0.3G4	HAT-P-2 b	9J-1.2R5	HD 12661 c	2J0.4W0	HD 178911 B b	6J-0.5G1
61 Vir b	5E-1.3R1	HAT-P-20 b	7J-1.4R0	HD 126614 b	7N0.4W4	HD 179079 b	25E-1R1
70 Vir b	7J-0.3G4	HAT-P-21 b	4J-1.3R2	HD 128311 b	2J0W3	HD 179949 b	18N-1.3R0
alf Ari b	2J0.1R3	HAT-P-22 b	2J-1.4R0	HD 128311 c	3J0.2F2	HD 180314 b	22J0.1G3
BD+48 738 b	17N0G2	HAT-P-23 b	2J-1.6R1	HD 130322 b	1J-1.1R0	HD 180902 b	2J0.1G1
BD+48 738 b	17N0G2	HAT-P-24 b	13N-1.3R1	HD 131496 b	2J0.3G2	HD 181342 b	3J0.3G2
BD+20 1790 b	7J-1.2G1	HAT-P-25 b	11N-1.3R0	HD 131664 b	18J0.5F6	HD 183263 b	4J0.2W4
BD-10 3166 b	9N-1.3R1	HAT-P-26 b	19E-1.3R1	HD 134987 c	15N0.8F1	HD 183263 c	4J0.6F3
BD-17 63 b	5J0.1F5	HAT-P-27 b	12N-1.4R1	HD 134987 b	2J-0.1G2	HD 185269 b	17N-1.1R3
CoRoT-1 b	1J-1.6R0	HAT-P-28 b	12N-1.4R1	HD 136418 b	2J0.1G3	HD 187123 b	10N-1.4R0
CoRoT-10 b	3J-1G5	HAT-P-29 b	14N-1.2R1	HD 137388 b	4N-0.1W4	HD 187123 c	2J0.7F3
CoRoT-11 b	2J-1.4R0	HAT-P-3 b	11N-1.4R0	HD 13931 b	2J0.7F0	HD 18742 b	3J0.3G2
CoRoT-12 b	1J-1.4R1	HAT-P-30 b	14N-1.4R0	HD 139357 b	10J0.4G1	HD 188015 b	1J0.1W2
CoRoT-13 b	1J-1.3R0	HAT-P-31 b	2J-1.3R2	HD 141937 b	10J0.2W4	HD 189733 b	1J-1.5R0
CoRoT-14 b	8J-1.6R0	HAT-P-32 b	17N-1.5R2	HD 142 A b	1J0W4	HD 190228 b	5J0.4W4
CoRoT-16 b	10N-1.2R3	HAT-P-33 b	14N-1.3R1	HD 142022 A b	5J0.5F5	HD 190360 c	18E-0.9R0
CoRoT-17 b	2J-1.3R0	HAT-P-4 b	13N-1.4R0	HD 142245 b	2J0.4G3	HD 190360 b	2J0.6F4
CoRoT-18 b	3J-1.5R1	HAT-P-5 b	1J-1.4R0	HD 142415 b	2J0W5	HD 190984 b	3J0.7F6
CoRoT-19 b	1J-1.3R0	HAT-P-6 b	1J-1.3R0	HD 145377 b	6J-0.3G3	HD 192263 b	13N-0.8G0
CoRoT-2 b	3J-1.6R0	HAT-P-7 b	2J-1.4R0	HD 145457 b	3J-0.1R1	HD 192310 b	17E-0.5G1
CoRoT-20 b	4J-1R6	HAT-P-8 b	1J-1.3R0	HD 1461 c	6E-1R0	HD 192310 c	24E0.1W3
CoRoT-21 b	3J-1.4R0	HAT-P-9 b	12N-1.3R0	HD 1461 b	8E-1.2R1	HD 192699 b	3J0.1G1
CoRoT-23 b	3J-1.3R2	HD 102117 b	3N-0.8R1	HD 147513 b	1J0.1W3	HD 195019 b	4J-0.9R0
CoRoT-3 b	22J-1.2R0	HD 102195 b	8N-1.3R0	HD 148156 b	16N0.4W5	HD 196050 b	3J0.4W2
CoRoT-4 b	13N-1R0	HD 102272 c	3J0.2G7	HD 148427 b	18N0G2	HD 196885 A b	3J0.4W5
CoRoT-5 b	9N-1.3R1	HD 102272 b	6J-0.2R1	HD 149026 b	7N-1.4R0	HD 19994 b	2J0.2G3
CoRoT-6 b	3J-1.1R1	HD 102329 b	6J0.3G2	HD 1502 b	3J0.1G1	HD 200964 c	1J0.3G2
CoRoT-7 b	5E-1.8R0	HD 102956 b	1J-1.1R0	HD 152581 b	2J0.2G2	HD 200964 b	2J0.2G0
CoRoT-7 c	8E-1.3R0	HD 104985 b	6J-0.1R0	HD 153950 b	3J0.1W3	HD 202206 b	17J-0.1W4
CoRoT-8 b	4N-1.2R0	HD 106252 b	8J0.4F5	HD 154672 b	5J-0.2G6	HD 202206 c	2J0.4F3
CoRoT-9 b	16N-0.4G1	HD 106270 b	11J0.6W4	HD 154857 b	2J0.1G5	HD 20367 b	1J0.1W2
eps Eridani A b	2J0.5F7	HD 10647 b	17N0.3W1	HD 156411 b	14N0.3W2	HD 2039 b	5J0.3W7
Fomalhaut b	3J2.1F1	HD 10697 b	6J0.3W1	HD 156668 b	4E-1.3R0	HD 204941 b	5N0.4F4
gam 1 Leo A b	9J0.1R1	HD 108147 b	5N-1R5	HD 158038 b	2J0.2G3	HD 205739 b	1J0G3
gam Ceph A b	2J0.3G0	HD 108863 b	3J0.1G1	HD 160691 d	10N0W1	HD 206610 b	2J0.2G2
GJ 1214 b	6E-1.9G3	HD 108874 c	1J0.4F3	HD 160691 c	11E-1R2	HD 208487 b	8N-0.3G2
GJ 436 b	23E-1.5R2	HD 108874 b	1J0W1	HD 160691 b	2J0.2W1	HD 20868 b	2J0W8
HD 209458 b	13N-1.3R0	HD 47536 b	5J0.2R2	HD 98219 b	2J0.1G2	Saturn	6N1F1g
HD 210277 b	1J0W5	HD 49674 b	2N-1.2R2	HD 99492 b	2N-0.9G3	tau Boo b	4J-1.3R0
HD 210702 b	2J0.1G2	HD 50499 b	2J0.6F2	HD 99492 c	7N0.7F1	TrES-2 b	1J-1.4R0
HD 212771 b	2J0.1G1	HD 50554 b	5J0.4W5	HD 99706 b	1J0.3G4	TrES-3 b	2J-1.6R0
HD 213240 b	5J0.3W5	HD 52265 b	1J-0.3G4	HIP 13044 b	1J-0.9R3	TrES-4 b	17N-1.3R0
HD 216435 b	1J0.4W1	HD 5319 b	2J0.2G1	HIP 14810 d	11N0.3W2	ups And d	10J0.4W3
HD 216437 b	2J0.4W3	HD 5891 b	8J-0.1R1	HIP 14810 c	1J-0.3G2	ups And b	13N-1.2R0
HD 216770 b	12N-0.3G4	HD 62509 b	3J0.2G0	HIP 14810 b	4J-1.2R1	ups And c	15J-0.1G2
HD 217107 b	1J-1.1R1	HD 6434 b	7N-0.9G2	HIP 57050 b	0N-0.8W3	ups And e	1J0.7F0
HD 217107 c	2J0.7F5	HD 6718 b	2J0.6F1	HIP 57274 d	10N0W3	V391 Peg b	3J0.2G0
HD 217786 b	13J0.4W4	HD 68988 b	2J-1.1R1	HIP 57274 b	11E-1.2G2	WASP-1 b	16N-1.4R0
HD 218566 b	4N-0.2W3	HD 69830 b	10E-1.1R1	HIP 57274 c	8N-0.7G1	WASP-10 b	3J-1.4R1
HD 219828 b	21E-1.3R0	HD 69830 c	12E-0.7G1	HIP 75458 b	9J0.1G7	WASP-11 b	9N-1.4R0
HD 222582 b	8J0.1W7	HD 69830 d	18E-0.2W1	HR 810 b	2J0G2	WASP-12 b	1J-1.6R0
HD 224693 b	13N-0.6R1	HD 70642 b	2J0.5F1	kappa CrB b	2J0.4W2	WASP-14 b	8J-1.4R1
HD 23079 b	3J0.2W0	HD 7199 b	5N0.1W2	Kepler-10 b	0E-1.8R0	WASP-15 b	10N-0.3G0
HD 231701 b	1J-0.3G1	HD 72659 b	3J0.7F2	Kepler-10 c	0N-0.6G0	WASP-16 b	16N-1.4R0
HD 23596 b	8J0.5W3	HD 73256 b	2J-1.4R0	Kepler-11 c	14E-1R0	WASP-17 b	9N-1.3R0
HD 240237 b	5J0.3R4	HD 73267 b	3J0.3F3	Kepler-11 g	18N-0.3G0	WASP-18 b	10J-1.7R0
HD 25171 b	1N0.5W1	HD 73526 b	3J-0.2G2	Kepler-11 b	4E-1R0	WASP-19 b	1J-1.8R0
HD 27442 b	1J0.1G1	HD 73526 c	3J0G1	Kepler-11 f	4M-0.6G0	WASP-2 b	16N-1.5R0
HD 28185 b	6J0W1	HD 73534 b	1J0.5W0	Kepler-11 d	6E-0.8R0	WASP-21 b	6N-1.3R0
HD 28254 b	1J0.3W8	HD 74156 b	2J-0.5G6	Kepler-11 e	8E-0.7G0	WASP-22 b	1N-1.3R0
HD 28678 b	2J0.1G2	HD 74156 d	7N0G3	Kepler-12 b	8N-1.3R0	WASP-23 b	16N-1.4R1
HD 290327 b	3J0.5F1	HD 74156 c	8J0.5W4	Kepler-16(AB) b	6N-0.2W0	WASP-24 b	1J-1.4R0
HD 30177 b	8J0.4F2	HD 7449 b	1J0.4W8	Kepler-17 b	2J-1.6R0	WASP-25 b	1N-1.3R0
HD 30562 b	1J0.4W8	HD 7449 c	2J0.7F5	Kepler-4 b	24E-1.3R0	WASP-26 b	1J-1.4R0
HD 30856 b	2J0.3G2	HD 75289 b	8N-1.3R0	Kepler-5 b	2J-1.3R0	WASP-28 b	1N-1.3R0
HD 31253 b	1N0.1G3	HD 75898 b	3J0.1G1	Kepler-6 b	12N-1.3R0	WASP-29 b	5N-1.3R0
HD 32518 b	3J-0.2R0	HD 76700 b	4N-1.3R0	Kepler-7 b	8N-1.2R1	WASP-3 b	2J-1.5R0
HD 33142 b	1J0G2	HD 7924 b	9E-1.2R2	Kepler-8 b	11N-1.3R0	WASP-31 b	0N-1.3R0
HD 33283 b	6N-0.8R5	HD 80606 b	4J-0.3G9	KOI-196 b	9N-1.5R0	WASP-32 b	4J-1.4R0
HD 33564 b	9J0W3	HD 81040 b	7J0.3F5	KOI-423 b	18J-0.8R1	WASP-33 b	5J-1.6R0
HD 34445 b	15N0.3W3	HD 81688 b	3J-0.1R0	KOI-428 b	2J-1.1R0	WASP-34 b	11N-1.3R0
HD 3651 b	4N-0.5G6	HD 82886 b	1J0.2G3	ksi Aql b	3J-0.2R0	WASP-36 b	2J-1.6R0
HD 37124 c	12N0.2W1	HD 82943 c	2J-0.1G4	Lupus-TR-3 b	15N-1.3R0	WASP-37 b	2J-1.4R0
HD 37124 b	13N-0.3G0	HD 82943 b	2J0.1W2	OGLE-TR-10 b	13N-1.4R0	WASP-39	5N-1.3R0
HD 37124 d	13N0.4F2	HD 83443 b	8N-1.4R0	OGLE-TR-111 b	10N-1.3R0	WASP-4 b	1J-1.6R0
HD 38529 b	14N-0.9R2	HD 8535 b	13N0.4W2	OGLE-TR-113 b	1J-1.6R0	WASP-41 b	17N-1.4R0
HD 38529 c	18J0.6W4	HD 8574 b	2J-0.1G3	OGLE-TR-132 b	1J-1.5R0	WASP-43 b	2J-1.8R0
HD 38801 b	11J0.2W0	HD 86081b	2J-1.4R0	OGLE-TR-182 b	1J-1.3R0	WASP-44 b	1J-1.5R0
HD 39091 b	10J0.5W6	HD 86264 b	7J0.5W7	OGLE-TR-211 b	14N-1.3R0	WASP-45 b	1J-1.4R0
HD 40979 b	3J-0.1G3	HD 8673 b	14J0.5W7	PRS 1257+12 b	0M-0.7P0	WASP-46 b	2J-1.6R0
HD 41004 A b	3J0.2W4	HD 87883 b	12J0.6F5	PRS 1257+12 d	4E-0.3P0	WASP-48 b	18N-1.5R0
HD 4113 b	2J0.1W9	HD 88133 b	4N-1.3R1	PRS 1257+12 c	4E-0.4P0	WASP-5 b	2J-1.6R0
HD 4203 b	2J0.1W5	HD 89307 b	2J0.5F2	PSR 1719-14 b	1J-3.4P1	WASP-50 b	1J-1.5R0
HD 4208 b	15N0.2W0	HD 89744 b	7J-0.1G7	Qatar-1 b	1J-1.6R0	WASP-51 b	14N-1.4R0
HD 4308 b	13E-0.9R3	HD 92788 b	4J0W3	rho CrB b	1J-0.7G0	WASP-6 b	9N-1.4R1
HD 4313 b	2J0.1G0	HD 9446 b	13N-0.7G2	Venus	15M-0.1G0t	WASP-7 b	18N-1.2R0
HD 43197 b	11N0W8	HD 9446 c	2J-0.2G1	Uranus	15E1.3F0i	WASP-8 b	2J-1.1R3
HD 44219 b	11N0.1W6	HD 95089 b	1J0.2G2	Earth	1E0W0t	XO-2 b	11N-1.4R0
HD 45350 b	2J0.3W8	HD 96063 b	17N0G3	Jupiter	1J0.7F0g	XO-3 b	12J-1.3R3
HD 46375 b	5N-1.4R0	HD 96127 b	4J0.1R3	Mercury	1M-0.4G2t	XO-4 b	2J-1.3R0
HD 47186 b	23E-1.3R0	HD 96167 b	13N0.1G7	Neptune	1N1.5F0i	XO-5 b	1J-1.3R0
HD 47186 c	7N0.4W2	HD 97658 b	6E-1.1R1	Mars	2M0.2W1t

Data from the Extra-solar Planets Catalog were used (Schneider et al., 2011) in this table.

1

Y. Dutil [Chaire de recherche industrielle en technologies de l'énergie et en efficacité énergétique (T3E) École de Technologie Supérieure] private communication.

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