TOI-4515 b
TOI-4515 b is a cold gas giant orbiting the G8/G9 star TOI-4515 in the constellation Pisces. It lies about 631 light-years from Earth and was discovered in 2024 using the transit method.
How Big Is TOI-4515 b?
TOI-4515 b has a radius of 12.17 times that of Earth, or 1.09 times the radius of Jupiter. Its mass is 637 times that of Earth, giving it a density of 1.94 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is TOI-4515 b in the Habitable Zone?
TOI-4515 b orbits inside the inner edge of the habitable zone of TOI-4515. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of TOI-4515: 0.584–1.389 AU (conservative: 0.739–1.317 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.
See the full interactive habitable-zone view in the Exoplanet Explorer app ›
Temperature on TOI-4515 b
The equilibrium temperature of TOI-4515 b is about 705 K (432 °C) — hot enough to melt many metals. This estimate ignores any atmosphere, which could change surface temperatures dramatically — Earth's greenhouse effect adds about 33 °C.
Orbit and Year Length
A year on TOI-4515 b — one full orbit around TOI-4515 — lasts 15.3 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.118 AU — closer to its star than Mercury is to the Sun. Its orbit is highly elliptical (eccentricity 0.46), swinging dramatically closer to and farther from its star.
How Was TOI-4515 b Discovered?
TOI-4515 b was discovered in 2024 using the transit method, with observations from Transiting Exoplanet Survey Satellite (TESS).
The transit method watches a star for the tiny, regular dip in brightness that occurs when a planet crosses in front of it. The depth and timing of these dips reveal the planet's size and orbital period.
How Far Away Is TOI-4515 b?
TOI-4515 b is 631.1 light-years (193.5 parsecs) from Earth. Light arriving here tonight left the planet around the year 1395. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 11,107,360 years to make the journey.
Earth Similarity Index
The Earth Similarity Index (ESI) scores how physically similar a planet is to Earth, from 0 to 1, based on radius, density, escape velocity and surface temperature. TOI-4515 b scores 0.10, ranking #4,480 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: TOI-4515
TOI-4515
- Spectral type
- G8/G9
- Surface temperature
- 5,433 K (Sun: 5,772 K)
- Mass
- 0.95 M☉
- Radius
- 0.86 R☉
- Luminosity
- 0.5810 L☉
- Age
- 1.2 billion years (Sun: 4.6)
Planetary System
TOI-4515 b is the only planet known to orbit TOI-4515 so far.
TOI-4515 b — Complete Data
| Radius | 12.170 Earth radii (1.086 Jupiter radii) |
|---|---|
| Mass | 637.00 Earth masses (2.005 Jupiter masses) |
| Density | 1.94 g/cm³ (Earth: 5.51) |
| Orbital period | 15.27 days |
| Orbital distance | 0.118 AU |
| Eccentricity | 0.461 |
| Equilibrium temperature | 705 K (432 °C) |
| Earth Similarity Index | 0.10 |
| Distance from Earth | 631.1 light-years (193.5 parsecs) |
| Constellation | Pisces |
| Discovery method | Transit |
| Discovery facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery year | 2024 |
Data: NASA Exoplanet Archive, last updated 2024-03-10. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About TOI-4515 b
Is TOI-4515 b habitable?
No — TOI-4515 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is TOI-4515 b?
TOI-4515 b is about 631 light-years from Earth in the constellation Pisces. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 11,107,360 years to get there.
How big is TOI-4515 b compared to Earth?
TOI-4515 b has 12.17 times the radius of Earth and about 637 times its mass.
How long is a year on TOI-4515 b?
One orbit around TOI-4515 takes 15.3 Earth days — short enough that 24 of its years would fit into one Earth year.
Explore TOI-4515 b in the app
Browse, filter and compare 6,000+ exoplanets on iPhone, iPad and Apple Watch — with habitable-zone views, widgets and offline data.
