With all the delightfully clear weather we’ve been having lately, now is an excellent time to share with you some research Gil did on star gazing websites. He wanted to find a URL that would tell him where to look for the Southern Cross and other constellations on any given date, as well as help him identify other points of light in the nighttime sky.
Gil has been using this website: www.fourmilab.ch/cgi-bin/Yoursky
Below are samples of what you will see at that website, as well as suggestions on how to use the menu choices offered there.
When you first go to the website you’ll see something like the screen shot below. Note the “Update” button at the bottom of the screen shot; this is the key button to click after making changes to the menu options which will be discussed next.
Scrolling down the webpage you will come to the menu options shown below. There are many choices for those of you who are astronomers and know about such things. Gil has inserted four red arrows showing inputs that he uses, that will bring up the sample screens shown further down in this blog. I’ll talk about those arrows in a moment.
The arrows are below the box where you can enter the date and time of the night sky you want to see. Note that the default of UTC time is five hours ahead of Cuenca’s, so you might want to adjust it. In the screen shot shown below, the website is showing the night sky for a UTC of 1:31 on August 8th, which is equal (subtracting five hours) to 8:31 pm on August 7th in Cuenca.
Here are explanations of each of those four red arrows:
The first arrow shows where you have to input the latitude and longitude for Cuenca. The website has many cities around the world that you can click on and have the lat-long coordinate automatically entered, but Cuenca isn’t one of those. So, you’ll need to input Cuenca’s latitude of2° 53' South and Longitude of 78° 59' West.(Note that sometimes when you change some of the menu choices the website will revert to a default latitude-longitude coordinate, so you need to periodically check that the website is set to Cuenca’s latitude-longitude coordinate.)
The second arrow shows the heavenly bodies that Gil wants to see, and accordingly the boxes that he has checked: “Moon and planets.”
The third arrow shows that Gil has clicked on the boxes that will allow him to see the names and outlines of constellations.
The fourth arrow shows that he has entered a value of 4.0 for the brightness of stars. This is a setting that means only really bright starts will be seen on his screen displays. A higher number will cause more stars to be visible. Note that you can also have the names of the stars displayed by checking the appropriate box (which Gil didn’t because the screen would become too cluttered with names.)
When Gil clicked the Update button after making the above menu changes, he sees this screen shot below, showing constellations and planets. He has added a red arrow showing the Southern Cross, a.k.a. Crux; at 8:30 pm on August 8th it’s in the southwest sky near the horizon. He has also inserted a red arrow at the bottom as a reminder to use the Update button.
The above screen shot also shows that four planets will be above Cuenca on that date at that time of night – Mars, Saturn, Pluto and Neptune Here is the list of standard symbols available at the web site.
In addition to the straight upward view, the website offers views toward the horizon. Below is the view of the constellations, etc., looking toward the southwest horizon; the Southern Cross (Crux) is visible above the gray animal that appears to be a squirrel. The website lets you pick any of eight compass directions – north, northwest, west, etc.
The website offers many other viewing options that amateur and not-so-amateur astronomers might have fun exploring. Enjoy!