1. Unit conversion 15 points
Convert PSR J0348+0432's orbital period (0.102424063 days) and semimajor axis (832000 km) to SI units (seconds and meters).
Problems
2. Total mass from Kepler’s third law 20 points
Using P² = 4π²a³/[G(m1+m2)] (the generalized two-body Kepler's third law, ASTR 310 Lecture 08), solve for the total system mass in solar masses.
3. Cross-check against the measured masses 15 points
The independently measured neutron star and white dwarf masses (Lecture 12/Lab 07) sum to 2.182 M⊙. Compute the percent agreement between your Problem 2 answer and this independently measured sum.
4. Synthesis 20 points
Write a short (150-200 word) paragraph explaining why this problem set's purely orbital (Keplerian) total-mass determination, agreeing with the independently measured individual masses (obtained via an entirely different method: pulsar timing plus white-dwarf spectroscopy), constitutes strong evidence for both results, in the same spirit as ASTR 310 Lecture 14's Alpha Centauri AB radiative/dynamical cross-check.
Due and Scope
Submit a complete derivation with equations, units, labeled quantities, and a short narrative interpretation for each problem. Show every step; a correct final number without a visible derivation receives partial credit at most, and quoting a lecture number without adapting it to this problem's specific inputs receives no credit for that step.
OpenStax Companion Reading
OpenStax Astronomy 2e (local reference copy: references/openstax-astronomy-2e-extracted.txt), Chapter 3.1-3.3 and Chapter 22.3-22.5.
References and Data Sources
- Corresponding lecture slides and notes for this unit.
- OpenStax Astronomy 2e (local reference copy: references/openstax-astronomy-2e-extracted.txt).
- Course datasets under
materials/ASTR330/data/where referenced above.