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Sky Show: Jupiter and Moon in Super Close Pairing

Two of the brightest objects in the night sky head towards a close encounter on Monday night. The sky show begins after local nightfall on the 21st when the waxing gibbous moon snuggles up to brilliant white Jupiter in the southeast. This closeness is of course just an illusion – they are in reality separate by hundreds of millions of kilometers.

Lunar conjunctions with planets are not that unusual, however they are rarely this close, says Raminder Singh Samra, a resident astronomer at the H.R. MacMillan Space Centre in Vancouver, Canada.

“Each month the Moon will pass by every planet in the night sky but they are usually a few degrees or few moons discs apart,” said Samra. ” This time we get to witness them passing within half a degree of each other – that’s less than the width of a finger held at arm’s length apart.”

If you miss this alignment, the next time Jupiter and the Moon will pass close to each other will be on March 17 but won’t appear to North Americans quite as close as this one. On August 2016 when the pair will appear even closer in North American skies.

Here are some of Samra’s observing tips…

Who can see event?

The cosmic encounter will be best seen throughout both of the American continents. The exact time the Moon appears closest to Jupiter will depend on location  – 7 p.m. in the Pacific time zone, 8:30 p.m. Mountain, 10 p.m. Central, and 11:30 p.m. Eastern time.  Some parts of South America will be in for a special treat as they will witness the Moon completely block out Jupiter in the sky.. for local observing times click onto the International Occultation Timing Association website (http://www.lunar-occultations.com/iota/planets/0122jupiter.htm).

 

What is happening?

Both the Moon and all the planets appear to follow the ecliptic line in the sky – the plane of the solar system through which all orbits are seen edge on from our line of sight here on Earth. The close proximity of the Moon to Jupiter in the sky however is just an optical illusion as they are actually very far apart. While the moon is on average 400,000 km from Earth, Jupiter sits 1700 times further away at about 680 million km.
 What is most unusual about this event?

This extra close encounter affords a unique opportunity for keen observers to try and spot Jupiter during daytime- before local sunset.  First step is to locate the Moon about halfway up the late afternoon southeast sky and then take binoculars to scan the sky just to its lower left. Special observing challenge will be to see how far before local sunset skywatchers can spot Jupiter in daylight.


How is it best seen?

The conjunction will be a very impressive sight for any observer regardless of location as long as there is a clear line of sight towards the southeast horizon. Even from large, light polluted cities, it promises to be easy to observe with nothing more than naked eyes. Train any sized optical aid on these worlds however, much more details can be glimpsed.

“For those who have a small telescope or a pair of binoculars the view will be greatly enhanced, as even with moderate power both the Moon and Jupiter will be visible at the same time,” adds Samra.

 

Update 20/1/2013 10 am EST : The story was originally published with errors on the actual distance separating the Moon and Jupiter and there is some confusion regarding this being the tightest conjunction until 2026. This claim appears to be the expectation for North Americans and is based on geocentric calculations (from the center of the Earth) which shows that on Oct.6, 2026 the two will be separated by only 0.17 degrees – as the conjunction would theoretically appear from the center of the Earth. But since we don’t skywatch from there, what an observer at the surface of our planet actually sees (ie. separation of the Moon from the planet in the sky)  depends on their geographical location.

 

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.

 

Comments

  1. mcthaniel
    fort wayne, Indiana
    January 24, 2013, 8:03 am

    just beutiful. end of discusion

  2. Barb
    Orange, California
    January 21, 2013, 9:39 pm

    Just walked in from viewing this cosmic event. Straight overhead.. Way cool. Beautiful clear night. Lots of stars visible.

  3. Annette Stanton
    South Dakota USA
    January 21, 2013, 8:34 pm

    I seen it! Great in the afternoon sky! Thanks for the heads up lol

  4. YungKoo, Kwun
    Seoul
    January 21, 2013, 8:04 pm

    It’s very easy~~
    See the Google Sky Map~~

  5. caroline
    italy
    January 21, 2013, 5:07 pm

    i live now in italy can i see that ,am so interesting and i always check in internet about the story of all sky

  6. Renato
    Rio - Brazil
    January 21, 2013, 11:37 am

    Will it be possible to see from Brazil?

  7. mhd Rafi
    gingee
    January 21, 2013, 2:55 am

    what happening in sky

  8. mhd Rafi
    gingee.tamil nadu
    January 21, 2013, 2:54 am

    when the moon is closer to jupiter but they seen closer in moon

  9. Santhosh
    India (Bangalore)
    January 20, 2013, 11:15 pm

    As i leave in INDIA i hope so i cant view it..
    I am waiting for the pics to be uploaded ASAP.
    Bit eagerness…
    Thanks for the pics and response in advance…

  10. MB
    January 20, 2013, 10:52 pm

    It was pretty bright tonight, you can see it already. It’s pretty cold here but the skies will be very clear! I had my eye on it while walking home.

  11. Michael
    Seoul
    January 20, 2013, 3:58 pm

    I live in Korea. Will I see anything?

  12. Dave Chapman
    Halifax, Nova Scotia
    January 20, 2013, 11:41 am

    With the Moon at 3 days past First Quarter, this event will certainly be the most easily observed close approach of Jupiter and the Moon for some time, globally speaking. Even the 2016 close approach occurs when the Moon is only 3 days old, setting before twilight ends. Most people will not see it. The close approaches in 2019 and 2023 take place when the both the Moon and Jupiter are lost in the Sun’s glare, hardly observable by anyone on this planet. The 2026 close approaches take place in the pre-dawn hours. Only lunatics are observing at that time! When it comes to what one reads in an astronomical table vs. what is observable, there are many shades of grey.

  13. Andrew Fazekas
    January 20, 2013, 10:52 am

    Thanks for the catch! The article has been revised and an update has been posted explaining the claims. In short the 2026 reference is based on geocentric calculations which has led to confusion and is just not practically applicable to skywatchers observing from different points around the world.

  14. Bruce McClure
    Norwood, NY
    January 20, 2013, 10:36 am

    Daniel,

    I’m guessing the claim of the closest Moon/Jupiter conjnction until 2016 originated with Joe Rao at http://www.space.com/19062-best-stargazing-events-2013.html. I have to agree with you that the statement is vague at best!

  15. Alan Eliasen
    January 20, 2013, 3:26 am

    This article has many fundamental errors:

    About the moon and Jupiter: “This closeness is of course just an illusion – they are in reality separate by nearly 130 million km.”

    Uh, the closest that Jupiter *ever* gets to earth is about 628 million km.

    In fact, the entire premise of the article is wrong. For example, the moon and Jupiter will be closer in the sky (reckoned from the center of earth and for most viewers on earth) on 2016-08-05, so the headline & premise of this article are wrong. They’ll be separated by less than half of the separation of this month. (2016 separation is 0.20 degrees, compared to this month’s 0.49 degrees.) Again, geocentric reckoning. Even closer than that on 2019-12-26, and so on. So the 2026 statement is baffling and repeatedly incorrect.

    I also want to note that the moon completely *occults* Jupiter as seen from southern Australia on February 18, 2013, so National Geographic’s international readers may also wish to point out this error. See:

    http://asa.usno.navy.mil/cgi-bin/occnwdo.cgi?dir=2013/occns&file=occn.2013Feb18.Jupiter&body=Jupiter

  16. Daniel Fischer
    Germany
    January 19, 2013, 8:13 pm

    Where did this false claim originate that “the next time Jupiter and the Moon will be this close won’t be until 2026″? Until that date there will be several occasions when the Moon is not only closer to Jupiter but will actually occult it! The next occasion after January 2013 (when such a disappearance of Jupiter behind the Moon can be enjoyed in South America) will aready be in … February 2013 when the same repeats for Australia. Perhaps the “closest” is true for (certain places in) North America, but then this should be clearly stated!