Before dawn beginning around October 24, 2015, get up early to see the planets Venus, Jupiter and Mars forming a planetary trio in the eastern sky. The planetary trio – any grouping of three planets inside a circle having a 50 diameter – will be visible from now until from about October 24 until around October 29. Venus, Jupiter and Mars are making up the first planetary trio on our sky’s dome since May, 2013. We won’t see a planetary trio again until January, 2021!
Binoculars typically have a field of view, or FOV of about 50. If you have binoculars, look for the letters FOV on them to find out its field of view.
You can also estimate 50 by holding your hand at an arm length from your eye, because the width of two fingers spans about 40 and the width of three fingers about 60 of sky.
Why are these planets near each other now? See below.
Venus (brightest), Jupiter (next-brightest) and Mars on the morning of October 22, 2015. Caught from Santa Fe by Matt Schulze.
Venus and Jupiter rank as the third-brightest and fourth-brightest celestial bodies in all the heavens, respectively, after the sun and moon. Therefore, you should have little trouble viewing these two luminaries at morning dawn. To view fainter Mars, though, you might need to get up an hour or more before sunrise, as Mars is some 250 times fainter than Venus, the sky’s brightest planet, and some 25 times fainter than Jupiter, the sky’s second-brightest planet.
Some of you might even catch a fourth planet – Mercury – over the horizon as darkness gives way to dawn. This particular morning apparition of Mercury favors the Northern Hemisphere. See chart below.
The green line depicts the ecliptic – Earth’s orbital plane projected onto the dome of sky. Click here to find an almanac giving you Mercury’s riseing into your sky.
Of course, if you can’t see Mars or Mercury with the eye alone, you can always aim binoculars at Venus and Jupiter to view Mars snuggling up with these brilliant beauties within a single binocular field, and then view Mercury near the horizon at dawn!
Why are these planets near each other now? The planets in our solar system orbit the sun in a single flat plane. In our sky, we look edgewise into the plane of the solar system to see the planets – and sun and moon – travel a single narrow pathway across our sky. The sun’s pathway is called the ecliptic. If you include the stars and constellations that lie along the ecliptic, you’re then talking about the Zodiac.
The planets orbit the sun at different speeds, with each planet outward from the sun moving around the sun more slowly. Thus Venus takes only a fraction of one Earth-year – only 225 days – to orbit the sun once. Mars takes about two Earth-years. And Jupiter takes about 12 Earth-years.
As we look outward from Earth, then, you can see that two planets must sometimes pass each other on our sky’s dome. These are the heralded conjunctions that people love to observe.
A planetary trio is even more special. It’s when three planets, all pursing their ordinary orbits around the sun, happen to pass near each other as viewed from Earth.
Enjoy this one! The next one won’t occur for some years.
Martin Marthadinata in Indonesia saw the planets like this on Saturday morning, October 17, when they were moving into position for late October’s planetary trio.
The morning planets can be seen from around the world. Here’s a photo of Saturday morning’s sky – October 17 – from Bashar Alaeddin in Amman, Jordan. In this photo, Mars is right next to Jupiter. By late October, Mars, Venus and Jupiter will all fit within a 5-degree circle.
Bottom line: A planetary trio is any grouping of three planets inside a circle 5 degrees wide. This one will be visible before dawn from now until around October 29. These morning planets are Venus, Jupiter and Mars. It’s the first planetary trio since May, 2013, and we won’t see one again until 2021!
from EarthSky http://ift.tt/1KSgQ8S
Before dawn beginning around October 24, 2015, get up early to see the planets Venus, Jupiter and Mars forming a planetary trio in the eastern sky. The planetary trio – any grouping of three planets inside a circle having a 50 diameter – will be visible from now until from about October 24 until around October 29. Venus, Jupiter and Mars are making up the first planetary trio on our sky’s dome since May, 2013. We won’t see a planetary trio again until January, 2021!
Binoculars typically have a field of view, or FOV of about 50. If you have binoculars, look for the letters FOV on them to find out its field of view.
You can also estimate 50 by holding your hand at an arm length from your eye, because the width of two fingers spans about 40 and the width of three fingers about 60 of sky.
Why are these planets near each other now? See below.
Venus (brightest), Jupiter (next-brightest) and Mars on the morning of October 22, 2015. Caught from Santa Fe by Matt Schulze.
Venus and Jupiter rank as the third-brightest and fourth-brightest celestial bodies in all the heavens, respectively, after the sun and moon. Therefore, you should have little trouble viewing these two luminaries at morning dawn. To view fainter Mars, though, you might need to get up an hour or more before sunrise, as Mars is some 250 times fainter than Venus, the sky’s brightest planet, and some 25 times fainter than Jupiter, the sky’s second-brightest planet.
Some of you might even catch a fourth planet – Mercury – over the horizon as darkness gives way to dawn. This particular morning apparition of Mercury favors the Northern Hemisphere. See chart below.
The green line depicts the ecliptic – Earth’s orbital plane projected onto the dome of sky. Click here to find an almanac giving you Mercury’s riseing into your sky.
Of course, if you can’t see Mars or Mercury with the eye alone, you can always aim binoculars at Venus and Jupiter to view Mars snuggling up with these brilliant beauties within a single binocular field, and then view Mercury near the horizon at dawn!
Why are these planets near each other now? The planets in our solar system orbit the sun in a single flat plane. In our sky, we look edgewise into the plane of the solar system to see the planets – and sun and moon – travel a single narrow pathway across our sky. The sun’s pathway is called the ecliptic. If you include the stars and constellations that lie along the ecliptic, you’re then talking about the Zodiac.
The planets orbit the sun at different speeds, with each planet outward from the sun moving around the sun more slowly. Thus Venus takes only a fraction of one Earth-year – only 225 days – to orbit the sun once. Mars takes about two Earth-years. And Jupiter takes about 12 Earth-years.
As we look outward from Earth, then, you can see that two planets must sometimes pass each other on our sky’s dome. These are the heralded conjunctions that people love to observe.
A planetary trio is even more special. It’s when three planets, all pursing their ordinary orbits around the sun, happen to pass near each other as viewed from Earth.
Enjoy this one! The next one won’t occur for some years.
Martin Marthadinata in Indonesia saw the planets like this on Saturday morning, October 17, when they were moving into position for late October’s planetary trio.
The morning planets can be seen from around the world. Here’s a photo of Saturday morning’s sky – October 17 – from Bashar Alaeddin in Amman, Jordan. In this photo, Mars is right next to Jupiter. By late October, Mars, Venus and Jupiter will all fit within a 5-degree circle.
Bottom line: A planetary trio is any grouping of three planets inside a circle 5 degrees wide. This one will be visible before dawn from now until around October 29. These morning planets are Venus, Jupiter and Mars. It’s the first planetary trio since May, 2013, and we won’t see one again until 2021!
from EarthSky http://ift.tt/1KSgQ8S
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