Category: Sky Events
Sky events
Mercury Exits the Dawn Sky
Mercury is sliding into the light of dawn this week. Currently about 10° elevation at sunrise, the planet will disappear into the Sun’s glare over the next few days. It will pass through superior conjunction on August 24th, to reappear for an evening apparition around September 8th.
New Moon
Perseid Meteor Shower
The Perseids are one of the most watched meteor showers. Occurring during northern hemisphere summer, the shower can be appreciated on a summer night. Quite a difference from the other reliable showers such as the Leonids and Quadrantids, that occur in November and January. Consider a warm summer night under a dark sky full of stars, a picnic blanket, relaxing while shooting stars streak across the sky. What could be better?
The Perseid meteor shower occurs when the Earth passes through a stream of debris along the orbit of Comet Swift-Tuttle. This shower has been consistent throughout recorded history, mentioned in Chinese, Japanese and Korean records as early as the 1st century. Active from July 17th to August 24th, the shower will build slowly for weeks before the peak. A week before or after peak the shower can still be seen with around 20 meteors each hour. The shower is a northern hemisphere event, for southern observers the radiant never rises above the horizon.
The Moon, Mercury, Mars and Jupiter
The dawn is getting crowded. While three planets, Mercury, Mars and Jupiter have been dancing on the dawn stage for weeks now, tomorrow morning a thin crescent, waning Moon will join in. Tomorrow morning the Moon will be 10% illuminated and 4.5° south of Jupiter.
Over the next couple mornings the Moon will continue to wane and slide along the line of planets in the dawn. On the morning of the 4th it will be 5% illuminated and between Mercury and Mars. On the 5th it will be lower than all three and only 1.6% illuminated.
Mercury at Maximum Elongation
Today Mercury reaches maximum elongation, the furthest point it will reach from the Sun in the sky and the highest it will be above the sunrise for this morning apparition. The planet is easily visible as a bright, starlike object about 19° above the rising Sun as the twilight begins. Over the next couple weeks Mercury will slide back into the sunrise, heading for superior conjunction on August 24th.
As Mercury passes through maximum elongation it is part of a trio of bright planets in the morning sky. Higher in the sky you will also see Jupiter and Mars dancing in the dawn.
Southern Delta Aquariids
The Southern Delta Aquariid meteor shower will peak this weekend. This reliable shower usually produces 10-20 meteors per hour. The peak will occur on July 27th this year. As the shower has a broad peak there should still be a good showing a few days either side of peak.
As we are past new Moon there is some dark sky available in the evening, best viewing for this shower is in the morning, when a bright 60% Moon will rise. Moonrise will occur around 22:00HST on the 27th and 22:43 on the 28th. The radiant for this shower will rise at 09:22HST. This provides a slim window of darkness to attempt meteor viewing. After rising, the moonlight will dim the prospects for viewing the shower.
Full Moon
Mars and Jupiter
Look for the pair to rise about 4:13am, almost two hours before the Sun. The two planets will be 20 degrees above the horizon at sunrise. They should be easy to spot with Jupiter at -2 magnitude and Mars dimmer but still easy at 1.5 magnitude. Look 8° below the pair for Mercury still rising towards maximum elongation.
Mercury Appears in the Dawn
Mercury will begin a morning apparition this week. The planet is currently about 10° above the rising Sun, climbing higher each morning. Look for a 3rd magnitude star-like object just above the glow of dawn. Mercury will reach a maximum elongation of 19° on July 29th.