Date: May 10th
Time: 12:00 AM/5:36(.22) AM--see detailed
Brief
At the end of yesterday's entry as a slight teaser, I brought up the topic of a high-in-the-sky asterism; one which is easily seen for half of mid-spring nights, starting at about midnight. That same figure is even more visible during the summer months. Naturally, I am talking about the Summer Triangle...yes, again! As we are now only about 6 weeks from the star of Summer, the triangle's stars are visible not long after dark, with Vega and Deneb already high above the horizon before 10 PM. Altair, not being as far north, rises last this evening at 11:15 PM for our location.
The 1st image shows the triangle looking east-northeast, as we begin a new day on the calendar.
Time: 12:00 AM/5:36(.22) AM--see detailed
Brief
At the end of yesterday's entry as a slight teaser, I brought up the topic of a high-in-the-sky asterism; one which is easily seen for half of mid-spring nights, starting at about midnight. That same figure is even more visible during the summer months. Naturally, I am talking about the Summer Triangle...yes, again! As we are now only about 6 weeks from the star of Summer, the triangle's stars are visible not long after dark, with Vega and Deneb already high above the horizon before 10 PM. Altair, not being as far north, rises last this evening at 11:15 PM for our location.
The 1st image shows the triangle looking east-northeast, as we begin a new day on the calendar.
Detailed
Although the Triangle is seen at its highest around this hour during most weeks of the summer, we can still see it as high just before the Sun's light washes them out; image 2 shows that, with Vega and Deneb not far from our zenith-- our highest point in the sky, or the equivalent of 90º altitude. If you remember my including the alt/az grid in past entries, I usually showed the horizon at 0º. This time, as well as the zenith marker, I will include the meridian and alt/az grid, since I am showing the Triangle at transit time for its center position.
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| click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp. |
For latitudes between 20 and 50º north, seeing the triangle at transit requires either lying on the ground (to avoid a stiff neck later!), or just looking straight up from a standing position. With most altitude and azimuth telescopes, this can be a little challenging with an eyepiece alone. Therefore, be sure to carry a diagonal with you, which puts the eyepiece parallel with the ground and easier for viewing comfort that way. The more north a viewer is, the lower the triangle transits. Of course if too far north, it never gets dark enough during some months to see it.
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