Understanding Astronomy Surface Gravity
How we calculate. g = 6.6743×10⁻¹¹ × M ÷ R² (SI). The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.
Real-world scenario: A typical Astronomy Surface Gravity case uses mass m (kg) 5.97e24 and radius r (m) 6.37e6. Enter the same figures below to reproduce the worked path.
What is Astronomy Surface Gravity?
A planetary/stellar surface-g KPI. Distinct from Physics weight (mg) on Earth-g assumptions.
- SI units (kg, m)
- Spherical teaching model
- G fixed on this page
The Formula
Worked Example
Common Use Cases
- Homework: planet g
- Study: pair with escape velocity
- Lab: SI drills
Pro Tips
- Convert km → m
- Don’t use Earth-g Physics weight for other worlds
- Pair with escape tool
Limitations: Astronomy Surface Gravity results are educational astronomy study aids—not navigation, mission planning, or professional observing advice. Confirm constants and units with your textbook or instructor.
FAQ
Same as Physics weight?
Physics weight is typically m×g with a given g. This page computes g from M and R.
Which G?
6.6743×10⁻¹¹ m³·kg⁻¹·s⁻².
Authoritative References
For astronomy study concepts, consult:
- OpenStax Astronomy — free textbook reference
- NASA — mission and outreach context
- IAU — astronomical constants and naming