Skywatch January 2014: Broken Comet, But Bright Planets

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Nature is very unpredictable; and we were reminded of this especially well in regard to comets. Despite the months-long major buildup about Comet ISON being the spectacular naked-eye “Comet of the Century”, nature provided a quite different outcome.Screen shot 2014-01-06 at 11.11.40 AM

Comet ISON was a “sun-grazing” comet. Its orbital path took it within 700,000 miles of the Sun. Though this sounds like a lot of miles, most comets pass millions of miles from the Sun. The Sun up close is frightfully hot and horribly deadly with harmful gamma rays, X-rays, and ultraviolet light. Ninety percent of Comet ISON was destroyed by this onslaught and though it had reached an apparent magnitude of -2.0 just before Thanksgiving, when it emerged from behind the Sun a few days later, there was not much left.

It was disappointing when the expected spectacular naked-eye comet did not materialize. But people connected with this comet as never before due to modern social media recording millions of hits from curious people; potential skywatchers. I was glad to see the interest it generated as I too, received numerous calls and questions leading up to Comet ISON’s swing around the Sun, and again afterwards, as people wondered what had happened.

The answer remains: Comets are probably the most unpredictable of celestial objects especially in regard to brightness. But one thing is sure. Comets are regular members of the Solar System and frequent visitors to the inner Solar System. Others will come and some may be bright and spectacular.

Meantime, the month of January features lots of action among the planets, with Jupiter reaching its closest approach to Earth in the last 13 months on January 5th, Venus visible low in the southwest at magnitude -4.4 until mid-January, and a fine appearance of Mercury in the West sky after sunset.

Venus will be unmistakable low in the southwest evening sky until about January 14th as its smaller orbit takes it close to the Sun, and then brings it into the Sun’s glare until late January,when it emerges into the eastern pre-dawn sky. It will be visible only for 30 to 40 minutes after sunset in early January in the southwest sky, but for 1 to 2 hours before sunrise in the East in late January and into February.

As twilight deepens Jupiter will rise among the stars of Gemini in the East reaching opposition January 5th. This means it is opposite the Sun in the sky as seen from Earth. Jupiter rises in the east as the Sun sets in the west and it is visible all night at magnitude -2.7! It will be hard to miss. On January 15th look for the Full Moon just a few degrees below Jupiter in the eastern evening sky.

Mercury gets to its greatest elongation (angle) from the Sun on January 31st. It will be seen in the southwest just left of where the Sun sets and about 10 to 12 degrees above that horizon, 45 to 60 minutes after the Sun goes down. A very thin crescent Moon will also be seen in the January 31st west sky just to Mercury’s lower right. Into February’s first days, the Moon will appear above and left of Mercury.

January’s Quadrantid meteor shower peaks on the night of January 3rd/4th. Look east-northeast from 4 to 6 am (I know, it is early and cold, but dark). You may see up to 60 meteors per hour.

January Moon Phases: 1st quarter Jan.7th; Full Jan. 15th; Last Quarter Jan.24.

August Skywatch: Planets, Metors; and Two Full Moons!

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Perseids meteor shower map

August begins with three bright first-magnitude objects, two of them planets, clustered near to each other in the southwestern evening sky for several hours after sunset. The planets are Saturn at magnitude +0.8 and Mars at magnitude +1.1. On August 1st they will be seen within 10 degrees of each other (Saturn above), and through the month they will appear to draw closer together. Between August 7th and 20th they will be within a 5 degree circle which will also include 1st magnitude (+1.0) Spica, the brightest star in the zodiac constellation Virgo. In fact on the night of the 7th, the three will actually appear to form a neat triangle!

Spica is a blue giant star some 4 times hotter than our Sun and while it does not appear to move out of its constellation from year to year because of its great distance from us, the planet’s do make noticeable changes against the background stars in their orbits around the Sun. Saturn is far enough away so that its changes against the stars are much less than Mars which, moves a lot faster. So Mars will appear to pass between Spica and Saturn so that on the nights of August 13 and 14, the three will look like they are in a nearly straight line. A week later on the 21st, the three will form another triangle shape, with a lovely crescent Moon joining them, just a few degrees below the line.

We can distinguish the three objects from each other by color. Mars is reddish-orange, while Saturn is a more golden-yellow, and Spica looks bluish-white. It will be fun watching during the month as the 3 appear to move around each other in the southwest sky (roughly 9 to 11 pm).

In the morning sky look East for Jupiter, rising about 2 am and then visible until sunrise and bright (-2.2 magnitude), and sitting some 5 degrees above Aldebaran, the brightest star in Taurus. On the morning of the 11th, the waning crescent Moon will be near Jupiter.

Even brighter Venus at –4.6 magnitude rises about 3 hours before the Sun and the crescent Moon will be seen near it on the morning of August 13th.

August always brings the best meteor shower of the year into view —– the Perseids —- so named because the meteors appear to come from the sky which is occupied by the constellation Perseus. Some years we have to compete with a bright Moon blocking our view of some of the meteors, but this year a waning crescent Moon will offer little competition, and the peak night is on a weekend. The best night is August 11/12 —- Saturday night into Sunday morning. Best views which may be up to 60 to 80 meteors per hour occur from midnight to dawn looking in the northeast sky halfway up from the horizon. Perseid meteors are hunks of rock and dust debris from Comet 109P Swift-Tuttle. Each August Earth plows through its debris field and the particles incinerate in our atmosphere by friction.

One other item of note this month is that August this year has two Full Moons —- August 1st and August 31st. Though two Full Moons in a single month happen about once every three and a half years, it is infrequent enough to be one reason for the expression “once in a blue Moon.” No, the Moon does not really turn blue when it is full twice in a month, but Earth atmospheric conditions do make the Moon look blue sometimes; and that is even rarer.

April Skywatch: Planets Still Dominate

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April will be dominated by Saturn and Mars when Saturn reaches opposition and peak visiblity on April 15th, and when Mars, as darkness falls, will be 2/3rds of the way up from the southeastern horizon among the stars of Leo the lion. But check out Jupiter and Venus in the southwestern sky just after dark.

Look first for Jupiter quite low in the west during April’s first two weeks. At magnitude -2.1 it will be an easy target but only 15 degrees above the horizon an hour after sunset. It should be visibible until about 10 pm, though with each passing
night it will appear lower and lower. By April 15th it will only be 5 degrees above the horizon an hour after sunset, and will set shortly thereafter. By the end of the month it will be gone until it reappears in the eastern morning sky in June.

Well above Jupiter you cannot miss Venus at magnitude -4.5 just below M45, the famous Pleiades star cluster, also known as the 7 sisters and in Japanese, as Subaru. From April 1 to 3 Venus will appear to move through the stars in the Pleiades cluster, which will make an especially nifty sight through a pair of binoculars or a telescope set with low power eyepiece. Venus will remain east (left) of the Sun all through April, which means this dazzling planet will be on display until at least 11 pm (local daylight time).

And it will actually get brighter —– to magnitude -4.7—- by the end of April, because its orbit will bring it closer to Earth. In a telescope its phase will appear to change from half-lit to one quarter-lit.

Mars in Leo at magnitude -0.4 outshines Leo’s brightest star, Regulus, and will be as close to this star as 4 degrees at mid-month. Mars will be distinctly reddish in color, while the hot star Regulus will look a bluish-white color; offering quite a nice contrast.

Saturn rises on April 15th in the east as the Sun is setting in the west; a position we call opposition. Saturn will be at +0.2 magnitude, a full magnitude brighter than Spica, the brightest star in Virgo the maiden. Spica is 5 degrees slightly below and right of Saturn all month, and on the night of April 6/7, the Full Moon will be nearby both of them. Telescopic views of Saturn, its famous rings, and multiple moons are always impressive; to newcomers at an eyepiece as well as to long-time skywatchers.

From April 16 to 25, but especially with a peak on April 21/22, look for the Lyrid Meteor Shower. Look north to northeast, from 2 to 5 am, toward the constellation Lyra the harp. No Moon will be in the sky to conflict with this shower, which frequently produces 20 to 25 meteors per hour.

The Full Moon of April 6th is the first Full Moon of Spring after the March 20th Vernal Equinox. Therefore by ancient design, Easer is celebrated on the first Sunday after this Full Moon. This year, then, Easter Sunday is April 8th. This is why Easter has a changeable date of observance every year. Last quarter Moon will be on April 13th; New Moon April 21st; and 1st quarter is April 29th.

March Skywatch: Planets Galore

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Just as in February, the planets of our solar system continue to be the prime focus for skywatchers in March. The two brightest planets, Venus and Jupiter, will join in a stunning conjunction in mid-month, while Mars will be seen better than we have seen in since 2010. Meanwhile, Mercury will put on its best evening appearance for 2012, and Saturn will brighten and appear earlier in the evening as it approaches its own opposition in April. Here are the details.

Jupiter

We will begin our planet watch with Mars which will shine bright at magnitude -1.2 when it reaches opposition on March 3rd. This is because Mars and Earth are coser to each other, at 63 million miles, than at any time since 2010. As the sky darkens in early March, look east, when Mars will rise there as the Sun sets in the west; then remaining visible all night. Though Mars will remain visible until next summer, March will be the only month when it will be really bright. Indeed, it will fade to -0.7 magnitude by the end of March. This is because Mars is actually quite small, being only 60% the size of Earth, and the distance between us and Mars will increase quickly as we move away from it in our smaller and fater orbit around the Sun. Mars will be seen among the stars of zodiac constellation Leo.

Mercury comes to greatest eastern elongation from the Sun on March 15th. It will be seen 18 degrees east of the Sun. That is to the left of the Sun as we look at it; so Mercury will be what the ancients called an “evening star.” Look in the direction of sunset, 30 to 90 minutes after the Sun goes down, and look about 10 to 12 degrees above the horizon. Mercury should be easy to spot at magnitude -0.4; but remember, it will be low in the sky. The sky too will retain some of the glow of twilight as you look, but Mercury is bright enough to shine through it.

Venus has also been an “evening star” these last two months, and it reaches its own eastern elongation from the Sun on March 27th; 46 degrees left of the Sun. It is unmistakable because it is so bright (-4.4 magnitude) and because it has a bigger orbit than Mercury, it gets farther away from the Sun. Consequently, it appears much higher.

Prior to Venus’s elongation, Jupiter and Venus will appear in close conjunction in the sky. On March 4th, the two planets will be about 9 degrees apart in the southwestern sky after dusk. The gap narrows so that between the 11th and the 15th of March, they will appeat just 3 degrees from each other. Venus will the the brighter, but Jupiter is no slouch in brightness, coming in at -2.1! This stunning pairing of the sky’s two brightest objects after the Sun and the Moon will be some 30 dgrees above the western horizon at sunset, and they will not set until after 10 pm!

The best way to enjoy this conjunction is with the naked eye or through binoculars, but both will be worthy telescopic objects individually throughout March.

Saturn rises about 10 pm in the east in mid-March, some 6 degrees above and left of Spica, the brightest star in Virgo. Best views of Saturn will come after midnight, when it is higher in the sky.

The busy month of March will close with some nifty views binocular views possible of Venus and the waxing crescent Moon passing just 2 degrees below the brightest planet. Full Moon will be on March 8/9th; Last Quarter on the 14th; New Moon on the 22nd; and 1st Quarter on the 30th.

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