Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; plgContentJComments has a deprecated constructor in /var/www/astarmathsandphysics/plugins/content/jcomments/jcomments.php on line 25 Call Stack: 0.0000 362456 1. {main}() /var/www/astarmathsandphysics/index.php:0 0.0927 1211800 2. Joomla\CMS\Application\SiteApplication->execute() /var/www/astarmathsandphysics/index.php:49 0.0927 1211800 3. Joomla\CMS\Application\SiteApplication->doExecute() /var/www/astarmathsandphysics/libraries/src/Application/CMSApplication.php:267 0.1640 4192888 4. Joomla\CMS\Application\SiteApplication->dispatch() /var/www/astarmathsandphysics/libraries/src/Application/SiteApplication.php:233 0.1654 4220456 5. Joomla\CMS\Component\ComponentHelper::renderComponent() /var/www/astarmathsandphysics/libraries/src/Application/SiteApplication.php:194 0.1662 4238168 6. Joomla\CMS\Component\ComponentHelper::executeComponent() /var/www/astarmathsandphysics/libraries/src/Component/ComponentHelper.php:356 0.1664 4268688 7. require_once('/var/www/astarmathsandphysics/components/com_content/content.php') /var/www/astarmathsandphysics/libraries/src/Component/ComponentHelper.php:381 0.1675 4291408 8. ContentController->execute() /var/www/astarmathsandphysics/components/com_content/content.php:42 0.1675 4291408 9. ContentController->display() /var/www/astarmathsandphysics/libraries/src/MVC/Controller/BaseController.php:710 0.2180 4961296 10. ContentController->display() /var/www/astarmathsandphysics/components/com_content/controller.php:113 0.2217 5153448 11. Joomla\CMS\Cache\Controller\ViewController->get() /var/www/astarmathsandphysics/libraries/src/MVC/Controller/BaseController.php:663 0.2222 5174376 12. ContentViewArticle->display() /var/www/astarmathsandphysics/libraries/src/Cache/Controller/ViewController.php:102 0.2344 5368568 13. Joomla\CMS\Plugin\PluginHelper::importPlugin() /var/www/astarmathsandphysics/components/com_content/views/article/view.html.php:189 0.2345 5368824 14. Joomla\CMS\Plugin\PluginHelper::import() /var/www/astarmathsandphysics/libraries/src/Plugin/PluginHelper.php:182

The Magnitude Scale

The magnitude scale is used by astronomers to compare the brightnesses of different stars – actually the apparent brightness. Originally, over 2,000 years ago, stars were given one of six classifications according to their brightness as seen by the naked eye. Very bright stars were given magnitude 1, while the faintest stars were given magnitude 6.

With modern technology, we can see stars much fainter than magnitude 6 and accurately measure the difference in the brightnesses of different stars. A magnitude 1 star is 100 times brighter than a magnitude 6 star – every difference of 1 in magnitude corresponds to a factor difference in relative apparent brightness of 2.512. The magnitude scale is logarithmic therefore. The magnitudes of some astronomical objects are shown below.

Example: Betelguese and Sirius have magnitudes of 0.50 and -1.46 respectively.

The difference in their apparent magnitudes is 0.50-(-1.46)=1.96.

Hence