This Week’s Sky at a Glance, August 15 – 23

Venus and Jupiter approach conjunction

Low in the dawn, bright Venus and Jupiter are approaching their very close August 18th conjunction.

Venus and Jupiter in conjunction, Aug. 18, 2014

Conjunction morning...

Venus and Jupiter just past conjunction.

...and two days later.

Friday, August 15

For the next several mornings, look low in the east-northeast about 45 to 30 minutes before sunrise for Venus and Jupiter very close together. On Saturday morning, these two brightest planets are still 2° apart, as shown at right. They'll be closest on Monday morning the 18th: just 0.2° or 0.25° apart at the time of dawn for Europe, 0.3° by the time dawn reaches the Americas. See our article, Venus-Jupiter Spectacle Coming August 18th.

Saturday, August 16

The two brightest stars of summer are Vega, overhead right after dark, and Arcturus, shining in the west. Vega is a white-hot type-A star 25 light-years away. Arcturus is an orange-yellow-hot type-K giant 37 light-years distant. Their color difference is fairly clear to the unaided eye. Both are dozens of times more luminous than the Sun.

Sunday, August 17

As dawn brightens on Monday morning, look for Jupiter and Venus having their very close conjunction low in the east-northeast, 0.2° or 0.3° apart, as shown below. The best view should be about 60 to 30 minutes before your local sunrise time.

The Moon is at last quarter (exact at 8:26 a.m. on the 17th EDT). It shines high in the southeast in early dawn on this date, with the Pleiades roughly a fist-width at arm's length to its left and a bit higher.

Monday, August 18

Look northeast as soon as the stars come out for W-shaped Cassiopeia. In twilight it's not quite as high as the Big Dipper is in the northwest, but right after dark, Cassiopeia and the Dipper reach their balance point. Summer is nearing its end.

Tuesday, August 19

If you're in the Earth's mid-northern latitudes, bright Vega passes close by your zenith just as night becomes fully dark. Whenever you see Vega at its closest to straight up, you know that Sagittarius, with its deep-sky riches, is at its highest in the south.

Wednesday, August 20

Roam the deep-sky sights just above the Sagittarius Teapot pattern with Sue French's "Deep-Sky Wonders" guided tour in the August Sky & Telescope, page 56. Do you know the Summer Christmas Tree?

Thursday, August 21

As soon as the stars come out, the Great Square of Pegasus stands low in the east. It's balancing on one corner, and your fist at arm's length fits inside it. It rises higher through the evening and floats highest overhead around 2 or 3 a.m.

Friday, August 22

Altair is the brightest star halfway up the southeastern sky after nightfall. Look to its left, by a little more than a fist at arm's length, for the dim but distinctive constellation Delphinus, the Dolphin. He's leaping to the left, just below the Milky Way.

Saturday, August 23

August is prime Milky Way time. After dark, the Milky Way runs from Sagittarius and Scorpius in the south-southwest, up and left across Aquila and through the big Summer Triangle very high in the southeast and east, and on down through Cassiopeia to Perseus rising low in the north-northeast.

 


Want to become a better astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.

This is an outdoor nature hobby; for an easy-to-use constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential guide to astronomy. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).

Pocket Sky Atlas

The Pocket Sky Atlas plots 30,796 stars to magnitude 7.6 — which may sound like a lot, but it's still less than one per square degree on the sky. Also plotted are many hundreds of telescopic galaxies, star clusters, and nebulae.

Once you get a telescope, to put it to good use you'll need a detailed, large-scale sky atlas (set of charts). The standards are the little Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger and deeper Sky Atlas 2000.0 (stars to magnitude 8.5); and once you know your way around, the even larger Uranometria 2000.0 (stars to magnitude 9.75). And read how to use sky charts with a telescope.

You'll also want a good deep-sky guidebook, such as Sue French's Deep-Sky Wonders collection (which includes its own charts), Sky Atlas 2000.0 Companion by Strong and Sinnott, the bigger Night Sky Observer's Guide by Kepple and Sanner, or the beloved if dated Burnham's Celestial Handbook.

Can a computerized telescope replace charts? Not for beginners, I don't think, and not on mounts and tripods that are less than top-quality mechanically (able to point with better than 0.2° repeatability, which means fairly heavy and expensive). As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."


This Week's Planet Roundup

Mercury is hidden deep in the glow of sunset.

Venus (magnitude –3.8) and Jupiter (a sixth as bright at magnitude –1.8) shine close together low in the east-northeast during dawn all week. They appear closest together in conjunction on Monday the 18th, just 0.2° or 0.3° apart. See our article, Venus-Jupiter Spectacle Coming August 18th.

Mars and Saturn, both magnitude +0.6, glow in the southwest at dusk. Mars is the lower one. They're drawing closer together every day. On Friday the 15th they're still 6½° apart. They'll pass 3½° apart on August 23–26.

Between them early in the week is the wide binocular double star Alpha Librae, magnitudes 2.8 and 5.2. Later it moves to their right.

Uranus (magnitude 5.8 in Pisces) and Neptune (magnitude 7.8 in Aquarius) are well placed in the southern sky in the early-morning hours. Finder charts for Uranus and Neptune.


All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America.

Eastern Daylight Time (EDT) is Universal Time (UT, UTC, or GMT) minus 4 hours.


"The universe is full of magical things patiently waiting for our wits to grow sharper."

— Eden Phillpotts, "A Shadow Passes," 1918


 

3 thoughts on “This Week’s Sky at a Glance, August 15 – 23

  1. Babu-Ranganathan

    SCIENCE SHOWS THAT THE UNIVERSE CANNOT BE ETERNAL because it could not have sustained itself eternally due to the law of entropy (increasing net energy decay, even in an open system). Einstein showed that space, matter, and time all are physical and all had a beginning. Space even produces particles because it’s actually something, not nothing. Even time had a beginning! Time is not eternal.

    The law of entropy doesn’t allow the universe to be eternal. If the universe were eternal, everything, including time (which modern science has shown is as physical as mass and space), would have become totally entropied by now and the entire universe would have ended in a uniform heat death a long, long time ago. The fact that this hasn’t happened already is powerful evidence for a beginning to the universe.

    Popular atheistic scientist Stephen Hawking admits that the universe had a beginning and came from nothing but he believes that nothing became something by a natural process yet to be discovered. That’s not rational thinking at all, and it also would be making the effect greater than its cause to say that nothing created something. The beginning had to be of supernatural origin because natural laws and processes do not have the ability to bring something into existence from nothing. What about the Higgs boson (the so-called “God Particle”)? The Higgs boson does not create mass from nothing, but rather it converts energy into mass. Einstein showed that all matter is some form of energy.

    The supernatural cannot be proved by science but science points to a supernatural intelligence and power for the origin and order of the universe. Where did God come from? Obviously, unlike the universe, God’s nature doesn’t require a beginning.

    EXPLAINING HOW AN AIRPLANE WORKS doesn’t mean no one made the airplane. Explaining how life or the universe works doesn’t mean there was no Maker behind them. Natural laws may explain how the order in the universe works and operates, but mere undirected natural laws cannot explain the origin of that order. Once you have a complete and living cell then the genetic code and biological machinery exist to direct the formation of more cells, but how could life or the cell have naturally originated when no directing code and mechanisms existed in nature? Read my Internet article: HOW FORENSIC SCIENCE REFUTES ATHEISM.

    WHAT IS SCIENCE? Science simply is knowledge based on observation. No one observed the universe coming by chance or by design, by creation or by evolution. These are positions of faith. The issue is which faith the scientific evidence best supports.

    Some things don’t need experiment or scientific proof. In law there is a dictum called prima facie evidence. It means “evidence that speaks for itself.”

    An example of a true prima facie would be if you discovered an elaborate sand castle on the beach. You don’t have to experiment to know that it came by design and not by the chance forces of wind and water.

    If you discovered a romantic letter or message written in the sand, you don’t have to experiment to know that it was by design and not because a stick randomly carried by wind put it there. You naturally assume that an intelligent and rational being was responsible.

    I encourage all to read my popular Internet articles: NATURAL LIMITS TO EVOLUTION and HOW FORENSIC SCIENCE REFUTES ATHEISM

    Visit my newest Internet site: THE SCIENCE SUPPORTING CREATION

    Babu G. Ranganathan*
    (B.A. Bible/Biology)

    Author of popular Internet article, TRADITIONAL DOCTRINE OF HELL EVOLVED FROM GREEK ROOTS

    *I have given successful lectures (with question and answer period afterwards) defending creation before evolutionist science faculty and students at various colleges and universities. I’ve been privileged to be recognized in the 24th edition of Marquis “Who’s Who in The East” for my writings on religion and science.

  2. Richard-Laughlin

    The best match for observed red shift is to proportionally decrease the speed of light from infinite at the Big Bang and increase the electron rest mass. The make the Big Rip 22 billion years from now also the Big Crunch, when a slow enough speed of light turns the Milky Way into a black hole. Nuclear molecules with valence helium-6-2 predate the Big Bang, making the supernova created Th-232-90 14.1 billion year half life the age of the Universe. Speed of sound today behaves as light inside a black hole, requiring at least electrons to propagate. Two neutrino bursts hours apart came from supernova 1987A. The first would make an ordinary neutron star. The second would convert matter to dark matter to change the speed of lepton-based radiation, as the core is now stable even as a black hole where the intense magnetic field of the neutron star now has mass. When the event horizon is outside a dark matter star’s radius, a stellar mass black hole prevents light from leaving the surface. Conditions needed for life in the Universe, would have by intense pressure, strong enough chemical bonding in a salty ocean of liquid metallic hydrogen, next to hydrothermal vents powered by natural nuclear reactors inside gas giant planets, before intelligent life on Earth.
    Ignore the speed of light when nuclear reactor critical mass is in use, to get the term God to Earth, as the two cherubims or dorsum on the Arc of the Covenant use the gold-metal approach of critical mass to make two living dolls. Angel and devil, both on the shoulders of a boy, are the best known dorsum. Planet Venus, 35 miles up levitated by Earth’s atmosphere use is home to the angel, and the red glowing surface is home to the devil. Mithras used astrology instead of center of the Earth for theology, and Michael the Archangel fighting the seven-headed dragon Satan or Tiamat, allowed Jews to define Saint John as a corrupter of Hebrew to the old Babylonian gospel hour, before John’s execution.

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