Morning Star Venus and Sirius shine from the eastern sky during morning twilight during September.
by Jeffrey L. Hunt
Brilliant Venus shines from the eastern sky during early morning twilight. The planet gleams in our sky from reflected sunlight. This morning the planet is nearly 82 million miles away.
Sometimes Venus is called the “Earth’s Twin” planet because the two planets are similar in size. Venus is completely veiled in clouds that are highly reflective. They return to space nearly 70% of the sunlight that falls on them. The clouds, oceans, and continents of Earth reflect about 40% of the sunlight that reaches them.
Sirius is visible low in the east-southeast during morning twilight. Sirius, the brightest star in Canis Major (Great Dog), is 8.6 light years away. The star is over 20 times brighter than our sun.
For the next several weeks, the brightest star and the brightest planet shine in the morning sky.
While brighter than our central star, Betelgeuse and Rigel in Orion to the upper right of Sirius, are considerably farther away.
Betelgeuse shines with the energy of over 13,000 suns.
Betelgeuse is a red supergiant – meaning that it is unusually large and intrinsically bright. At a distance of about 500 light years, this enormous red star would cover several planets’ orbits if it were in our solar system.
Rigel, a topaz blaze in the morning sky, is even brighter. It shines with the power of over 40,000 suns.
The spacing of Betelgeuse, Sirius, and Procyon in the sky make the Winter Triangle. This trio is prominently placed in the sky during the evenings of the winter months.
Sirius, a few weeks past its first morning appearance, now shines with other bright stars in the morning. Step outside and look the next clear morning for the brightest planet and the brightest star.
Here is a daily summary about the planets during September.
May 22, 2021: Five planets parade across the sky. Jupiter and Saturn are in the southeast before sunrise. Evening Star Venus, Mercury and Mars are in the western sky after sunset. A bright moon is in the southeastern sky.
May 21, 2021: Three bright planets are dancing in the western sky after sundown. Evening Star Venus is entering the sky for a months-long residency after its solar conjunction two months ago. Mercury is heading for a conjunction with Venus after its best evening appearance of the year. Mars continues its eastward march in Gemini, but time is running out on its appearance as it approaches brighter evening twilight and a conjunction with Venus.
May 21, 2021: At the weather warms, daylight and twilight lengthen to diminish nighttime hours. As the summer solstice approaches far northern latitudes do not have periods of darkness. From the most northern latitudes, the sun does not set – the Land of the Midnight Sun.
May 20, 2021: Evening Star Venus, Mercury, and Mars continue their planetary dance in the western sky after sunset. Begin looking for brilliant Venus about 30 minutes after sunset. Fifteen minutes later, Mercury and Mars join the ballet.
May 20, 2021: With two bright planets in the southeast before sunrise, the Summer Triangle – Vega, Altair, and Deneb – is high in the south as daylight approaches.