Spring has sprung, summer's here, etc.

To quote an old poem I learned once, "Spring has sprung, and fall has fell. Summer's here and boy is it hot."

In fact, summer has been here for several days. It's official beginning was on Saturday, June 21, at 4:51 a.m. MDT. That is when the Sun reached its most northern point for the year and Earth's axis is tilted 23.5 degrees toward the Sun and the Sun is over the Tropic of Cancer.

Well, it didn't actually cross the equator, because of that pesky 23.5 degree tilt of Earth's axis, as we orbit the Sun that tilt brings the northern hemisphere into direct sunshine and gives us longer days and shorter nights, ergo, summer.

That means, of course, our friends in the southern hemisphere are now starting to enjoy -- if that is the correct term -- winter. I have an astronomer friend in Australia and she was complaining that the temperatures were now hovering around zero degrees.

Just keep in mind that our friends there use the Celsius method of reckoning the temperatures, which means (in our way of thinking) it was right at 32 degrees Fahrenheit, it is still cold however you measure it.

Speaking of long days, the first day of summer was not technically our longest day. The length of day has been at 15 hours and one minute since Tuesday, June 17, and will be that way until tomorrow, June 26, when the days start to get shorter.

Now, to the night sky. Our old friend Jupiter has left the evening sky. Oh, you might still catch a glimpse of it low in the west after sunset, but by the time the sky gets dark enough to see things it will be below the horizon.

Fading Mars is still quite visible as is Saturn--even here in the bright sky of Denver--high in the south. Mars is the farthest west and Saturn is almost due south. If you are having trouble finding them, mark July 5th and 7th on your calendar.

On those dates the moon will pay a very, very close visit to both planets in the early evening hours. Will be a good watch in binoculars.

My grandson's favorite constellation, Leo, the Lion, is now starting its dive toward the western horizon. Led by the bright star Regulus and the distinctive backwards question mark indicating its head and mane it is just above the western horizon.

There are two other notable constellations that are summer-specific, and they can be found in the south in the late evening.

The first, Scorpius, the Scorpion, is almost due south at about 10:30 pm MDT, featuring bright Antares at its heart. Scorpius is one of the few constellations that actually looks like what it is supposed to be.

The three stars in a row for the head and the long fishhook shape down to the left for the body and infamous two stars at the end which mark the "stinger."

Later in the evening -- around 1:30 am actually -- the other specifically summer constellation of Sagittarius will be high in the south. If you look for a "teapot shape" you will have found it. More about both of them next month.

SKYWATCH: New moon, Friday, June 27.

NEXT WEEK: More astronomical blathering.