The Summer Triangle is a group of three bright stars in the summer sky. Each is the brightest star of the constellation they are in, and there are three constellations. Although they start in the summer, they last until the end of the year.
The three stars are Deneb, Vega, and Altair. Vega is in the constellation Lyra the Harp, Deneb is the tail star of Cygnus the Swan, and Altair is the eagle eye of Aquila the Eagle. If you hold your arm out straight and make a fist with your hand, the Summer Triangle is three fists wide and two fists high.
In June and July, it is above the eastern horizon, and in August and September it is high overhead. Then the rest of the year it is in the western sky. The reason it is called the Summer Triangle is because that is when it first appears. Vega is the highest star in the ENE. Altair is to its lower right closer to the east, and Deneb is below Vega to the left in the NE.
Now that summer is here, the full moon is tonight on June 24. Last night Mars popped into the Beehive Cluster M44 and will be there tonight as well. So, look in the west at least ½ hour after sunset to see Mars. Venus is to the lower right of Mars and may not rise for a while. Look as late as you can to see the two planets. Obviously, Venus will be very bright.
Jupiter and Saturn are now rising in the east close to midnight. Saturn rises first, and Jupiter rises about an hour later. As the night progresses, they move to the south which is where you will see them if you get up around 4:30 in the morning. If the sky is clear and dark, you may also see some of Jupiter's moons.
Mercury is beginning to rise in the early morning starting on June 30. It will be in the east rising about 4:30 a.m. Because we live in the southern US, it will be easier for us to find it. So, have fun looking for the planets.