Ellipses and their foci have a lot of useful properties. It so happens that an orbiting object traces out an ellipse, with the thing it orbits around at one of the focuses. Coincidence? Yes. I can’t find a good intuitive reason why orbits are elliptical. In fact, I...
Why are galaxies different shapes? How do the orbits of comets differ from planetary orbits? How are comets, asteroids, and meteors different? How are supernovae involved in new planet formation? Why does an elliptical galaxy look like one giant star? Why are there comets in the Oort cloud...
The Equation Of course, this is not true when a projectile is projected perpendicular to the Earth’s surface. To observe a parabolic trajectory, we must project it at some angle with the surface. Even though no horizontal forces affect a projectile following its launch, it is the initial ho...
The system works because the middle layer of the atmosphere, which is normally ice cold, becomes permeable to water in certain locations and at certain times of year. This is due to the way that Mars orbits around the Sun, in a highly elliptical orbit which brings it much closer to the ...
There are three primary reasons for whysatellitesare not sent straight up and out of the solar system: (1) doing so would require the satellite to cancel out its motion in the direction of Earth’s orbit, which would use a great deal of fuel; (2) most of the interest...
–As planetary sistems evolve, neighborhoods become increasingly “cleaner” with time, in average. In young systems, you’ll have planets as large as the Earth, or even larger, with “dirty” neighborhoods, wereas in old systems, smaller and smaller bodies get their orbits cleaned up. Ceres...
Not only might we be on the cusp of the great leap of life becoming multi-planetary, we may be on the cusp of a bunch of other great leaps as well. There are other signs pointing to this being an extraordinarily unusual time to be alive: For 99.8% of human history, the world ...
The reasons why Mercury does not have moons are pretty much the same for Venus, but there are a few additional considerations when it comes to the second planet from the sun. Venus is the second planet in the solar system. If there is a planet that is most similar to Earth, it’s Ve...
Like Earth, Pluto has a seasonal cycle due to theinclination of its polesto the plane of its orbit. Over the course of Pluto's long year – equivalent to 248 Earth years – first the north pole and then the south pole are angled toward the distant Sun. ...