Astronomy Homework Help

About Astronomy

Astronomy here sits where physics meets the sky: orbits and gravitation, satellites, the solar system, eclipses, stars and the scale of the universe. Many questions are gravitation problems in disguise — a satellite's speed, the period of an orbit, why the Moon does not fall — and reward treating them as mechanics.

Popular topics in Astronomy

• Gravitation

  Newton's law of universal gravitation, gravitational field strength, and weight against mass.

• Orbits & Satellites

  Orbital speed and period, geostationary satellites, escape velocity and energy in orbit.

• Kepler's Laws

  The three laws of planetary motion and deriving the inverse-square law from them.

• The Solar System

  Planets and their order, moons, asteroids and comets, and how the system is thought to have formed.

• Eclipses & Phases

  Solar and lunar eclipses, umbra and penumbra, the phases of the Moon and tides.

• Stars & The Universe

  Stellar life cycles, light-years and distance, galaxies, the big bang and the evidence for expansion.

How ScanSolve helps with Astronomy

ScanSolve treats an orbit question as a mechanics question: the gravitational force supplies the centripetal force, and the equation says so before any number appears. Units and powers of ten are carried explicitly, since astronomy arithmetic lives at 10^24 kg and 10^8 m.

Descriptive questions — eclipses, phases, stellar life cycles — are answered as sequences with the geometry stated, and where a diagram would settle it, the answer describes exactly what to draw.

Study tips for Astronomy

1. 01

   Write "gravitational force = centripetal force" as your first line in any orbit question. Nearly all of them start there.

2. 02

   Keep powers of ten in standard form all the way through. Entering 6.4e6 as 6400000 is where these calculations go wrong.

3. 03

   Distinguish mass from weight in your wording. Astronomy questions test the difference more often than any other topic.

4. 04

   For eclipse and phase questions, sketch the Sun, Earth and Moon positions before explaining. The geometry is the answer.

Frequently asked Astronomy questions

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