编辑“︁TOI-178”︁（章节）

== 軌道的共振 ==
根據IAU的{{link-en|系外行星命名慣例|Eexoplanet naming convention}}，這六顆行星命名為TOI-178b到TOI-178g，其外面的五顆行星被鎖定在[[軌道共振|拉普拉斯共振]]的鏈條中。它們繞行母恆星的軌道週期(以天為單位)是b=1.91、c=3.24、d=6.56、e=9.96、f=15.23、和g=20.71。這雖然不是一個完美的整數比，但存在一個參考系，它每天大約旋轉1.37°，行星連續的合形成了一個重複的模式<ref name=":1" />。對於在這個參考系內的觀測者而言，行星c到g形成了一個共振鏈，可以用週期比表示為 2:4:6:9:12，或是用軌道比表示為18:9:6:4:3。這意味著行星c每轉18圈，行星d就完成9圈、行星e轉6圈，行星f轉4圈，行星g轉3圈。

除此之外，行星b的軌道也很接近它共振鏈的一部分。在一個週期約比1.95天稍長的軌道上，它將與行星c形成一個3:5的共振；與其他五顆行星同一個共轉參考系中。有可能整個系統最初形成於一條長長的共振鏈中，但後來最裡面的行星可能被潮汐相互作用從中拉出<ref name=":1" />

{{clear}}

{{Orbitbox planet begin
| name = TOI-178
| table_ref =<ref name=":1" />
}}
{{OrbitboxPlanet
| exoplanet    = b
| mass_earth   = {{val|1.50|0.39|0.44}}
| period       = {{val|1.914558|0.000018}}
| semimajor    = {{val|0.02607|0.00078}}
| eccentricity = 
| inclination  = {{val|88.8|0.8|1.3}}
| radius_earth = {{val|1.152|0.073|0.070}}
}}
{{OrbitboxPlanet
| exoplanet    = c
| mass_earth   = {{val|4.77|0.55|0.68}}
| period       = {{val|3.238450|0.000020|0.000019}}
| semimajor    = {{val|0.0370|0.0011}}
| eccentricity = 
| inclination  = {{val|88.4|1.1|1.6}}
| radius_earth = {{val|1.669|0.114|0.099}}
}}
{{OrbitboxPlanet
| exoplanet    = d
| mass_earth   = {{val|3.01|0.80|1.03}}
| period       = {{val|6.557700|0.000016}}
| semimajor    = {{val|0.0592|0.0018}}
| eccentricity = 
| inclination  = {{val|88.58|0.20|0.18}}
| radius_earth = {{val|2.572|0.075|0.078}}
}}
{{OrbitboxPlanet
| exoplanet    = e
| mass_earth   = {{val|3.86|1.25|0.94}}
| period       = {{val|9.961881|0.000042}}
| semimajor    = {{val|0.0783|0.0023|0.0024}}
| eccentricity = 
| inclination  = {{val|88.71|0.16|0.13}}
| radius_earth = {{val|2.207|0.088|0.090}}
}}
{{OrbitboxPlanet
| exoplanet    = f
| mass_earth   = {{val|7.72|1.67|1.52}}
| period       = {{val|15.231915|0.000115|0.000095}}
| semimajor    = {{val|0.1039|0.0031}}
| eccentricity = 
| inclination  = {{val|88.723|0.071|0.069}}
| radius_earth = {{val|2.287|0.108|0.110}}
}}
{{OrbitboxPlanet
| exoplanet    = g
| mass_earth   = {{val|3.94|1.31|1.62}}
| period       = {{val|20.70950|0.00014|0.00011}}
| semimajor    = {{val|0.1275|0.0038|0.0039}}
| eccentricity = 
| inclination  = {{val|88.823|0.045|0.047}}
| radius_earth = {{val|2.87|0.14|0.13}}
}}
{{Orbitbox end}}