Changing Planet

5 Sky Events This Week: Row of Planets, Summer Triangle

An artist's concept of the asteroid belt filled with rocks and dusty debris orbits our sun. Image credit: NASA/JPL-Caltech
An artist’s concept of the asteroid belt filled with rocks and dusty debris orbiting between the orbits of Mars and Jupiter. Image credit: NASA/JPL-Caltech


Evening planets continue to dazzle all week long, the largest asteroid in the solar system pays a brief visit, and an annual celestial landmark rises, signaling that summer is not too far off.

Mercury Meets Jupiter. Look towards the very low northwest horizon on Monday, May 27, about 30 minutes after sunset to catch a close encounter between the innermost and largest planets in our solar system. Mercury will pass only 2.4 degrees from Jupiter–little more than the width of a thumb at arm’s length. While both look like specks of light in our skies, it’s amazing to think of the enormous size difference between these two worlds: Mercury is 4,880 kilometers wide while Jupiter has a diameter of 142,740 kilometers.

Venus Joins Jupiter. The goddess of love gets her chance to dance with the king of all planets on Tuesday, May 28.  The planets will be only one degree apart–so close that you can cover both worlds with just your pinky or little finger at arm’s length.

Ceres Asteroid. Got binoculars or a backyard telescope? Then starting Thursday, May 30 into the first week of June, try hunting down Ceres, the largest rock in the asteroid belt. This faint 7th magnitude star-like object is sailing through Gemini constellation and passing near Pollux, one of the twin’s super-bright stars. The best way to know for sure you’ve snagged this Texas-sized  space rock is by checking your views from night to night to see its movement in front of the static star field.

Planetary Lineup.  A great way to finish the month, on Friday, May 31, three planets form a near-perfect diagonal line after sunset. The faintest but highest in the sunset sky is Mercury, to its lower right is a bright Venus, followed by fading Jupiter. The cosmic trio will fit nicely into a a single field of view in binoculars, spanning about seven degrees, slightly more than the width of 4 fingers at arm’s length. The following days will see the planets continue to move apart, with Jupiter disappearing in the twilight glare.

THree bright stars form a giant triangular formation known as the Summer Triangle rising in the east near local midnight, Credit: Starry Night Software/A.Fazekas
Three bright stars form a giant triangular formation known as the Summer Triangle rising in the east near local midnight. Credit: Starry Night Software/A.Fazekas


Summer Triangle Rising. Next Saturday, June 1, look toward the low eastern sky around  midnight local time for the brilliant Summer Triangle. This famous giant triangular formation of three bright stars begins to rise earlier and higher the closer summer approaches. The highest, top corner star is Vega, the brightest star in this part of the sky. To its lower left is Deneb, while to its far lower right is Altair.

Tell us—what amazing sky phenomena have you seen lately?


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.
  • F.A. Hutchison

    Your articles always so slanted to the Northern Hemisphere. There are people who read your site/Magazine who live ‘down under.’ Possible to include us when talking about the sky?

  • disdik

    amna be wailin

  • Andrew

    In ‘Mercury meets Jupiter’ the last sentence reads “…it’s amazing to think of the enormous size difference between these two worlds…” – but the article then proceeds to give the figures in kilometres. Having been brought up in the UK I’m afraid that metric measurements such as these mean very little to me. I have no concept of the sizes. Could you please also include the imperial equivalents so that the many British readers like me brought up in the British culture can have some concept of these figures. After all, an author’s purpose is to present their articles and narratives in such a way that as many readers as possible understand the content. Thank you.

  • Andrew

    Further to my previous post – the article spells ‘kilometres’ incorrectly anyway!

  • Jose Socorro Murillo Gudiño

    Mercury,Venus and Jupiter triangle 27 May 2013…amazing

  • Michael

    Andrew, you are too close minded. First of all, the metric system is the most common system in the world. Just because you have no concept of the most common system (part of SI, the world-wide standard) doesn’t make the author wrong. Also, the UK commonly spells words with ‘re’ instead of ‘er’, and the USA is the opposite. Considering National Geographic is an American publication, *any* reasonable person would expect the author to use the metric system, and spell it the American way. Asking and expecting anything different is selfish and close minded.

  • Violet

    Andrew, that is how it’s spelled in the US

  • Josh

    Andrew if this article was written by someone from the USA they would spell it kilometers as apposed to kilometres. I’m Canadian so it’s kilometres here as well haha

  • maxin

    Impresionante poder ver la creacion de DIOS mediante las photos de natgeo:thanks nat geo

  • Angela

    All I have seen here is clouds and more clouds the past two weeks. I’m missing all the great stuff ~-~

    Also, Andrew, kilometers is also correct. You can spell is kilometers or kilometres depending on country. I am American but I constantly spell theater as “theatre” and people try to tell me that is incorrect. It really just depends on where the author grew up. Besides, Google is useful for distance conversions–though I understand the convienence of having it in the article.

  • Ivan

    No offence, but we (Croatians) for exaple use metric measurements so I can understand it, and on many articles online you can find imperial measures instead.
    Luckily, there are tons of converting calculators… If I need to use it sometimes, you could use it too, if you want to know more… 🙂

  • Kenneth Gedelian

    Or u can just convert the measurements online…You know U can do that…Man people are so lazy Will find anything to complain about Geez

  • Kenneth Gedelian

    Great Article Thanks for the “Heads Up” 🙂

  • jason

    i agree with hutchinson; many of us are avid night watchers, but find it frustrating to read these cool articles as they dont consider those other than americans?…

  • myira smith

    i love the planet and the whole solar system and im the only one in my family and i never get a chance to go out and see it

  • Ben Dover

    this absolutley fasinating

  • Pedro

    I agree with F. A. Hutchinson.

    When you write articles that are destined to go on any site on the world wide web, writers need to be aware that it is a WORLD-WIDE web, not just northern USA, not even just northern hemisphere.
    Be aware of your readership!
    Be a WORLD citizen.

  • Harry

    Andrew you’re a muppet. I’m sure your fellow, more industrious, Brits could just use the Internet to get a conversion.

    That’s what I would do

  • reza gholamipour

    the altair aqual to bird. this word(altair) is arabic and aqual to bird(الطیر)

  • Pete

    Andrew there are two correct spellings of the word Kilometer. He used the US spelling correctly. And to help you out a little mi =km * 0.62137. Who cares how it is described if you have even the slightest grasp of math?

  • Chris
  • Frank

    Andrew, grow up. Grab a converter and stop whining

  • Pansy Burke

    Congratulations Andrew on your new accomplishment! Keep up the SUPERB work!!!

  • Addie

    Yes, we witnessed it in Malaysia. i was having a pool party last monday (Malaysia’s time) with some friends and i saw some weird things in the skies. a dude came to me and said what it was. we thought that it can be only seen in the western sky…

  • victor okoth

    am so fascinated by all these, i enjoy astronomy and i wont miss that chance to view the spectacular bodies

  • Michael

    Andrew, quit your gibberish and go to elementary school or something. Space science wouldn’t get through your thick skull anyway.

  • fred

    andy is a Canadian and should state northern skys get your own sky guy for southern skys what a bunch of whinners

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