OUTSIDE SPACE – They have been there much longer than we have, and we will be long gone before they disappear, but Saturn and Jupiter will join this year’s Great Conjunction for just a little bit of a cosmic moment.
In anticipation of the 2020 Great Conjunction, where Saturn and Jupiter will merge into one point of light on Monday, December 21, two Utah astronomers offer their insight and advice to fellow stargazers.
“I’m not going for the clarity or even the cleanliness of this event,” said NASA Solar System Ambassador Patrick Wiggins of the importance of the event. “I’m pushing the rarity.”
Wiggins is not exaggerating when he said that if you do your best to see the powerfully bright point of light that will be Saturn and Jupiter next Monday, you will see a sight not seen by any of your fellow travelers on Earth before. Since the days of Galileo, who was the first to see Jupiter’s satellites in a telescope, the two gas giants have not appeared so close, NASA reported.
BYU astronomy professor Denise Stephens has encouraged her astronomy students to search for the two planets after returning home for Christmas. They should be able to watch them come together no matter where in the world they are, Stephens said.
But back in Utah, we may face unique challenges. First, you have to be fast.
“It’s going to be sort of a race,” said Wiggins of the need to look for the conjunction early.
Both astronomers suggest observing the sky about an hour after sunset, when the two planets will be low enough on the horizon that mountains to the west can block the view. To find out if this is a problem for you, Wiggins suggested hitting the road right now and tracking Jupiter and Saturn every night. If you can’t see them today because of an obstruction, you won’t see them on the 21st.
And if you start observing the two planets now, you will notice that they are getting closer each night. This is seeing “the solar system in motion,” said Wiggins.
The erratic weather in Utah can also stop the show. Starlight cannot shine through clouds, but Jupiter is bright enough to break through Utah’s northern inversion, Wiggins said.
Jupiter is the first bright “star-like” object to appear above the southwestern horizon, and Saturn, slightly fainter, follows above and to the left, Wiggins explained. Unlike much of the world right now, the two planets will not be socially distant on December 21. From Earth, it appears that the two are separated by the thickness of a dime held at arm’s length. However, both Wiggins and Stephens warn again not to expect a change in clarity.
While many call this a poinsettia, that doesn’t mean the two planets will give off extra light. Many believe that the star of Bethlehem could have been a planetary conjunction. Stephens said if this were the case, it would have stood out to the magicians symbolically, not necessarily visually. A Saturn-Jupiter conjunction, which took place around 7-8 BC, the far-sighted sages could have meant the birth of a merciful and righteous king – Jupiter represents grace and Saturn represents justice. A later Jupiter-Venus conjunction could have had a similar meaning, Stephens explained.
When asked about the significance of this year’s Great Conjunction, Stephens said, “I’m going to choose to see it as a sign of better things to come.”
How this much-discussed astronomical event will shine, however, is through proper optics.
“To look through a telescope, which has a very narrow field of view, and to see two planets at once, is a rare occurrence,” said Wiggins.
The veteran astronomer said he would start observing before the sun sets, although he doesn’t recommend that to greener astronomers. But anyone with even the most basic of telescopes should be able to see both Saturn and Jupiter at the same time in their telescope’s eyepiece. Jupiter and Saturn are two of the three objects in the sky that most impress humans, he stated. He himself remembers that his first observation of Saturn as a child was “incredible”!
The next Great Conjunction is in 80 years, Wiggins said. That means kids have a great opportunity to become returning eyewitnesses, as does Halley’s Two Timers’ Club, that of a previous generation that saw Halley’s Comet in 1910 and again in 1986. His advice to the youth: draw a picture of what you see. When the next Great Conjunction rolls around, you have a good story to tell – with evidence.
If you don’t have a telescope, binoculars are almost as good. Wiggins said that with a magnification of 20x you can distinguish Jupiter’s four satellites and the bulge of Saturn’s rings.
But if you can only observe with the naked eye, that’s okay too. “Look at it with your eyeball!” Wiggins encouraged.
Stephens showed the same enthusiasm.
“This will be a great way to end 2020,” she said.
Correction: An earlier version reported that Halley’s Comet was last visible in 1983; it was 1986.