I hope we have a break in the clouds!

From Sky and Telescope:

Earth’s two closest planetary neighbors draw strikingly close together this week.

When it comes to “eyeball astronomy,” nothing is more satisfying than to see a pair of celestial objects appear close together in the sky, what astronomers call a conjunction. And 2015, notes S&T‘s longtime contributing editor Fred Schaaf, truly deserves to be called the “Year of the Conjunctions.” In January we watched Venus and Mercury come together in the evening twilight, and this month features a similarly close and prolonged pairing of Venus and Mars. [“It’s still the same old story…”]

The two worlds have been edging closer together all month. Venus has become obvious in the southwest after sunset, and it’s been climbing a little higher week by week. Mars, meanwhile, has lingered in roughly the same part of the post-sunset sky for several months, refusing to depart. [Plus ça change…] Last week Mars was about 8° above Venus, but for a 9-day run beginning February 17th, the two remain within 2° of each other. That separation shrinks to less than 1° from the 20th through the 23rd.

Venus, Mars, and the Moon this week

The climax comes on February 21st, when the two planets are just 0.4° apart at dusk, as seen from the Americas. Since the pairing is so close, Schaaf cautions, “little Mars might be hard to see in Venus’s glare without optical aid.” [“… a case of do or die…”]

Both worlds will fit together in a medium-power telescopic view, with Venus clearly dominant — nearly 100 times brighter. Its dazzling yellow-white disk, shining at magnitude –3.9, is 12 arcseconds wide and 88% illuminated, whereas peach-colored Mars is much dimmer, magnitude +1.2 or +1.3, and just 4 arcseconds across.

As an added bonus, a thin crescent Moon is passing through this celestial scene. It clusters dramatically with the two planets in the deepening dusk on February 20th one day before Venus and Mars are closest. Get those cameras ready!


Very cool.

About Fr. John Zuhlsdorf

Fr. Z is the guy who runs this blog. o{]:¬)
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  1. acricketchirps says:

    That’s close! One of these days they’re gonna smack into each other–that’ll be a sight for your amateur astronomer*!

    * if the Sun’s not already exploding at the time, that is.

  2. john_6_fan says:

    The waxing crescent moon last night was ludicrously thin and beautiful. I think locally, we’re going to be overcast for this conjunction. Bummer.

  3. The Masked Chicken says:

    If no one minds me recommending some good free astronomy software/stuff for the general public (since I search the Internet for good free stuff – or am I just cheap?):

    1. Stellarium – best free, open source planetarium software there is. Available for all platforms.
    2. Celestia – excellent space simulator, on par with Stellarium.
    3. Virtual Moon Atlas.
    4. Moonphase (for Windows, only)
    5. AstroFly (Windows, only)
    6. HNSKY (planetarium)
    7. SkyChart
    8. SkyOrb (many platforms)
    9. Orbiter (fly a spaceship into space)

    Best astronomy podcast: Astronomy Cast. Dr. Pamala Gay is a Christian (who has taken grief because of it) and her co-host, Frazer Cain is an atheist.

    Binocular astronomy is cheap and fun. There are many good books and web sites. It is one of the few sciences not messed with by the U. S. Department of Homeland Security, unlike chemistry sets and lasers.

    The Chicken

  4. Kathleen10 says:

    This is very cool. I’m going out to look despite the fact that our wind chills are about -10 right now.
    Hey Chicken, thank you for the great list. I’m writing those down. Please let me know when affordable jet packs come out. I have waited for jet packs all my life and so help me if they hand them out when I’m 80 I’m going up.

  5. Nicholas says:

    So, Father, would this be a conjunction junction?

  6. APX says:

    And here I got excited thinking this would be about grammar.

  7. iamlucky13 says:

    “And here I got excited thinking this would be about grammar.”

    Et me quoque!

    Seriously though, I would be remiss after my critique of the vortices video earlier this week if I didn’t thank Father for bringing more attention to this sweet conjunction of three of the brightest objects in the night sky.

    Unfortunately, like all interesting astronomical phenomena, Western Washington has scheduled clouds to block the view, so I don’t expect to see it.

  8. ejcmartin says:

    Thank you for the heads up. Just happened to have read this before heading to Mass this evening. There it was right in front of me as I drove in the church parking lot. Amazing.

  9. DebbieInCT says:

    hahaha, APX, that made me laugh out loud! Thanks for this post Fr. Z. Since I read it earlier today, I knew to look up in the sky when I got home from work – and there it was! just so beautiful!!

  10. Grateful to be Catholic says:

    Thanks for the tip, Fr. Z. Without it, I would never have ventured out in the dark and cold. Clear skies in DC gave a beautiful view. It will be snowing here tomorrow so that’s it.

  11. JonPatrick says:

    Chicken thanks for the list of astronomy software. I am in the process of downloading Stellarium. Note that the latest release of this software requires graphics hardware that supports OpenGL 2.1. I have an older system (Dell Optiplex 755) that apparently does not, so I read that you can download the older version 12.4 which will run with the older hardware.

  12. jfk03 says:

    Saw The conjunction last night. Different angle from the edge of Pacific Ocean at approx lat 42 degrees. Took photo, but ’twas a bit shaky since I didn’t have tripod with me and used 200 mm lens. Very pretty with crescent moon.

  13. SanSan says:

    Wow, I saw it! My prayer partner and I were outside of PP for 40 Days for Life at dusk…….we both noticed the cresent Moon and what we thought we’re two stars….one brighter than the other……little did we know that we were looking at Venus and Mars. I remember thinking how beautiful God’s creation was as I sat in front of a disgusting abortion mill with passerbys a jeering. Thanks for the info Father Z.

  14. The Masked Chicken says:

    There is, as I mentioned, a lot of free software for astronomy out there and I have only scratched the surface. The entire Messier star catalog is available for download and there are high-resolution maps of the moon that would fill your entire computer screen. For instance:

    Simply put, there is an amazing amount of armchair astronomy that one can do at a computer. Do you want to do comet hunting and possibly get a comet named after you? Many people use the SOHO site:

    People track objects over months as they approach the sun using the images from this site. Those little flecks might be comet trails.

    Do you want to do real science and make a contribution, then help classify galaxies:

    Do you want to look through real telescopes over the internet? Then, there are sites for you (some cost money, because they are real research sites): (costs money) (free and really cool)

    Do you want to study astronomy with real data over the internet, they have a nice European site (including access to radio telescopes):

    You can do webcam astronomy:

    I don’t want to overload the combox with links, but if you want to learn about astronomy, there is a lot available.

    The Chicken

  15. FrAnt says:

    I saw the conjunction. It was beautiful. I was getting into my car going to celebrate the Stations of the Cross, I stopped and thought of the power and glory of God in both creation and in Jesus, who died for us. Thanks be to God.

  16. KateD says:

    We saw this last night and commented on how incredible it was, but we didn’t know what it was. Thank you for the post!

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