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Archive for August, 2014

08/20/2014 – Ephemeris – Where are the bright planets for this week?

August 20, 2014 2 comments

Ephemeris for Wednesday, August 20th.  The sun rises at 6:50.  It’ll be up for 13 hours and 48 minutes, setting at 8:39.   The moon, 3 days past last quarter, will rise at 3:17 tomorrow morning.

Wednesday is bright planet day on Ephemeris.  Reddish Mars is on the western edge of Libra the scales, skirting below Saturn in the southwest as darkness falls.  It will set at 11:23 p.m.  Saturn will be in the southwest, above and left of Mars as darkness falls.  It will set at 11:50 p.m.  Saturn’s is still great viewing with small or large telescopes to see those fabulous rings and its large moon Titan.  Mars will pass Saturn traveling eastward next Wednesday.  Brilliant Jupiter will rise in the east-northeast at 5:03 a.m. in morning twilight, followed by the brighter Venus, which will rise 17 minutes later.  Jupiter is increasing its distance from the sun, while Venus is retreating toward the Sun from our point of view

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Evening planets

Mars and Saturn with the stars of the zodiac from Virgo to Sagittarius at 10 p.m. August 20, 2014. Created with Stellarium.

Saturn

Saturn and moons through a telescope on August 20, 2014. Created using Stellarium.

Morning planets

Jupiter, Venus and the Moon and winter stars at 6 a.m. August 21, 2014. Created using Stellarium.

The Moon

The crescent Moon as seen in binoculars at 6 a.m., August 21, 2014. Created using Stellarium.

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08/19/2014 -Ephemeris – Scutum’s place in history

August 19, 2014 Comments off

Ephemeris for Tuesday, August 19th.  The sun rises at 6:49.  It’ll be up for 13 hours and 51 minutes, setting at 8:41.   The moon, 2 days past last quarter, will rise at 2:26 tomorrow morning.

Yesterday we took a look at the wonders in the constellation of Scutum the shield above the Teapot of Sagittarius and below Aquila the eagle.  Scutum is the shield of John Sobieski the Polish king who stopped the advance of the Turks at Kalenberg in 1683. The Polish half of me is very proud.  Scutum is one of two official constellations which are related to a real person.  The other one is Coma Berenices, a hank of the Egyptian queen Berenice’s hair.  However the stars here are so dim and embedded in the glow of the Milky Way as to be nearly impossible to discern.  Scutum lies in one of the richest portions of the Milky Way, wonderful to scan with binoculars and telescopes for star clusters and nebulae or clouds of dust and gas.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Deep sky objects in Scutum & Sagittarius

Binocular and telescope deep sky objects in Scutum and Sagittarius. Created using Stellarium.

08/18/2014 – Ephemeris – Scanning the Milky Way in Scutum

August 18, 2014 Comments off

Ephemeris for Monday, August 18th.  The sun rises at 6:48.  It’ll be up for 13 hours and 54 minutes, setting at 8:43.   The moon, 1 day past last quarter, will rise at 1:37 tomorrow morning.

The teapot pattern of stars that is the constellation of Sagittarius lies at the southern end of the Milky Way this evening. It appears that the Milky Way is steam rising from the spout.  The area above Sagittarius in the brightest part of the Milky Way is the dim constellation of Scutum the shield.  Don’t bother looking for the stars that make up the constellation; what’s important is the star clouds of the Milky Way.  Scan this area with binoculars or small telescope for star clusters and nebulae or clouds of gas.  In binoculars both clusters and nebulae will appear fuzzy, but a small telescope will tell most of them apart.  Even if you’ve never been able to find anything in your telescope, use your lowest power and scan.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

The constellations Sagittarius and Scutum. Created using Stellarium.

The constellations Sagittarius and Scutum. Created using Stellarium.

08/15/2014 – Ephemeris – Jupiter and Venus will appear to cross paths Monday morning

August 15, 2014 Comments off

Ephemeris for Friday, August 15th.  The sun rises at 6:45.  It’ll be up for 14 hours and 2 minutes, setting at 8:47.   The moon, 2 days before last quarter, will rise at 11:33 this evening.

Over this weekend the planets Venus and Jupiter will be seen to approach each other.  In reality Jupiter is five times the Earth’s distance behind the sun, while Venus is about 70 percent of Earth’s distance behind the sun.  Most of the motion against what stars can be seen after 5:30 a.m. will be Venus, being dragged by the sun plus its own orbital motion toward the east.  Jupiter is moving eastward too, but is taking its sweet time of 12 years to orbit the sun.  The planets will cross, or be in conjunction at about midnight Monday morning, before they rise.  By the time they will rise around 5:12 a.m. the two planets will be half the width of the Moon apart, slightly farther apart than they were at midnight.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

 

Jupiter and Venus

Watch Jupiter and Venus approach each other and separate. From August 15 to August 18, 2018. Created using Stellarium and GIMP.

08/14/2014 – Ephemeris – The Milky Way now spans the sky in the evening

August 14, 2014 Comments off

Ephemeris for Thursday, August 14th.  The sun rises at 6:43.  It’ll be up for 14 hours and 5 minutes, setting at 8:49.   The moon, 3 days before last quarter, will rise at 10:58 this evening.

We’ll get a bit of darkness tonight, but it will be the start of about two weeks of the best sky viewing of the year.  Now is the time the summer Milky Way is displayed to its fullest to the southern horizon.  City folk come to our area and are sometimes fooled by the brightness and expanse of the Milky Way and think it’s clouding up.  Yes those are clouds indeed, but they are star clouds.  Binoculars will begin to show them to be millions of stars, each too faint to be seen by themselves to the unaided eye, but whose combined glow give the impression of a luminous cloud.  Binoculars are the ideal tool to begin to explore the Milky Way.  Objects still too fuzzy can be checked out with a telescope to reveal their true nature.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

All sky view of the Milky Way

The Milky Way at 10 p.m. on August 14, 2014. Residual glow in the west is from the Sun, to the east is for the Soon to rise Moon. There is also an odd artifact connected to the solar glow.  Created using Stellarium.

08/13/2014 – Ephemeris – This week’s parade of the bright planets

August 13, 2014 Comments off

Ephemeris for Wednesday, August 13th.  The sun rises at 6:42.  It’ll be up for 14 hours and 8 minutes, setting at 8:51.   The moon, 3 days past full, will rise at 10:24 this evening.

Wednesday is bright planet day on Ephemeris.  Reddish Mars is between the constellations of Virgo and Libra, approaching Saturn in the southwest as darkness falls.  It will set at 11:40 p.m.  Saturn will be in the southwest, above and left of Mars as darkness falls, in the Libra the scales.  It will set at 12:16 a.m.  Saturn’s is still great viewing with small or large telescopes to see those fabulous rings and its large moon Titan.  Mars will pass Saturn traveling eastward later this month on the 27th.  Brilliant Venus will rise in the east-northeast at 5:03 a.m. in morning twilight.  Below left of Venus, we welcome back Jupiter which will rise at 5:23 tomorrow morning.  Jupiter and Venus will appear to cross paths on the 18th.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Mars and Saturn

Mars and Saturn with the zodiacal constellations Virgo, Libra, Scorpius and Sagittarius at 10 p.m. August 13, 2014. Created using Stellarium.

Telescopic Saturn

Saturn and its moons. Small telescopes will reveal only Saturn and Titan. Created using Stellarium.

Binocular Moon

The Moon low in the east at 11 p.m. Created using Stellarium.

Venus and Jupiter

Venus and Jupiter at 6 a.m. in the bright morning twilight with the rising stars of winter. Created using Stellarium.

08/12/2014 – Ephemeris – Comet Swift-Tuttle progenitor of the Perseid meteors

August 12, 2014 Comments off

Ephemeris for Tuesday, August 12th.  The sun rises at 6:41.  It’ll be up for 14 hours and 11 minutes, setting at 8:52.   The moon, 2 days past full, will rise at 9:50 this evening.

The Perseid meteor shower will reach its peak later this evening.  The moon will still interfere with all but the brightest meteors.  The meteors are caused by bits of sand grain to pea sized rubble given off by Comet Swift-Tuttle on past runs through the inner solar system.  As comets go Comet Swift-Tuttle is large, with a nucleus of some 16 miles  (26 km) in diameter.  Comet Halley’s nucleus is half that and Churyumov–Gerasimenko’s nucleus that ESA’s Rosetta spacecraft is now orbiting is half Halley’s.  Despite the wear and tear that a comet’s nucleus must endure when coming close to the Sun, the distribution of debris to give us a pretty even annual meteor shower means the comet has been near its present orbit for a very long time.
Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Comet Swift-Tuttle orbit

Orbit of Comet 109P/Swift-Tuttle. Blue line is the comet’s orbit, coming from above. Credit NASA / JPL / Applet by Osamu Ajiki (AstroArts), and further modified by Ron Baalke (JPL)

Link to the animation from which the above image was taken and other information on Comet Swift-Tuttle go to http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=109P;cad=1