Explosive events on the solar surface release energy in various forms, e.g., accelerated particles, bulk mass motion, and radiated emission in various spectral ranges. A solar flare is an explosion on the Sun that happens when energy stored in twisted magnetic fields (usually above sunspots) is suddenly released. Flares produce a burst of radiation across [...]
Archive for the ‘Terminology’ Category
Solar flare classification
Posted in Astronomy, Physics, Terminology, tagged science, solar on March 10, 2011 | Leave a Comment »
Telescopes: basic parameters
Posted in Astronomy, Terminology, tagged telescopes on January 26, 2011 | Leave a Comment »
It happens quite often to ask if a specific telescope can “show” a certain object with given magnitude. For this reason, it is useful to keep in mind a few simple relations giving the basic properties of telescopes.In this post, I explain three parameters: Limiting magnitude, resolving power, and the magnification. Limiting magnitude is the [...]
Why do I love CATs?
Posted in Astronomy, Terminology, tagged telescopes, wiki on January 23, 2010 | Leave a Comment »
A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses (dioptrics) and curved mirrors (catoptrics). Catadioptric combinations are used in focusing systems such as search lights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto lenses. Other optical systems that use lenses and mirrors are [...]
Sunspots
Posted in Astronomy, Photo, Terminology, tagged science, solar on January 11, 2010 | Leave a Comment »
Sunspots are intersection of the solar surface with a large magnetic flux tube. They appear in the activity belt, latitudes up to ±40° at the beginning of a solar cycle and tend toward equator at the end of a cycle. Formation time-scale of large sunspots is from a few hours to a few days. The [...]
Meteors and meteor showers
Posted in Astronomy, Meteor Shower, Photo, Terminology, tagged Leonids, Perseids, science on November 19, 2009 | Leave a Comment »
A meteor is the visible streak of light that occurs when a meteoroid enters the Earth’s atmosphere. Meteors typically occur in the mesosphere, and most range in altitude from 75 km to 100 km. Millions of meteors occur in the Earth’s atmosphere every day. Most meteoroids that cause meteors are about the size of a pebble. They [...]
