With bats patrolling the dusk air in search of mosquito treats and mosquitoes buzzing about me hoping for a nibble, my look at the not quite dark, evening sky was a quick one; but what a treat. The evening planets of the summer of 2014, Mars (right) and Saturn (left), are separated, almost equidistance, by our exactly quarter, moon (5:50pm EDT). Mid to high clouds make those three hazy here in central Virginia, for now obscuring any summer stars. But now, an hour later, post blog, the sky has cleared and the color differences of the two planets is stunning and spectacular, as are the summer stars.
Clouds have hidden the August sky to this point, three days in, blocking the slide of the growing crescent toward the two planets. The breaks and thinnings today revealed both our nearby star for the first time in August and finally the planet, moon trio. As the moon slips past Saturn during this next Earth rotation our lone satellite will occult - block - the ringed planet for Australian sky watchers as they move into Earth's shadow. Tomorrow night, here in Virginia, the then slightly gibbous moon will be left (east) of Saturn and while the moon will move away, Mars and Saturn will continue their slower eastward trek through the stars of Virgo and Libra before Mars catches and slides under and by Saturn later this month.
The largest full moon of the year is August 10 and slightly waning gibbous moon 2 and 3 days later will not make for a heavy dose of Perseid meteors this year. Maybe catch a lucky, early, atmosphere edge skimmer before the moon comes up and outshines all but the brightest shooting stars of one of the year's most consistent showers.
45 minutes before sunrise on August 18, Venus, alone in the pre-dawn sky for much of 2014, gets close company as the king of the planets, Jupiter, continues its rise into the morning sky. 5 days later the waning crescent moon forms a lovely triangle with the two brightest planets.
With the unusually cool and often clear skies brought to the east coast this year by the summer version of the polar vortex, August could be great for checking out the sights of our solar system. And, if you live where it's really dark, the sights way beyond out solar system and all the way to the heart of our Milky Way galaxy could be out there just waiting for your eyes to catch their long-travelled light...tonight on Earth!!
Sunday, August 3, 2014
Thursday, July 3, 2014
APHELION!
July 3 marks APHELION, the point in Earth's yearly elliptical orbit when our planet is the farthest from the sun. If you are in the northern hemisphere it may not feel like you are at the farthest distance from the very hot sun! Which helps make the point that our distance from the sun, and it varies by almost 3 million miles, has little or nothing to do with the seasons. Changes in the earth/sun distance may well factor into advances and recessions of vast ice sheets but as a yearly weather influence the distance is minimal; it's the TILT that causes the seasons on Earth (as it does on Mars).
Earth's tilt, slowly shifting between 22 and 24 degrees (another possible factor in the comings and goings of ice sheets) with respect to the plane of our orbit around the sun, is the reason it's cooking hot on July 3rd in central Va. Our current tilt of 23 1/2 (actually 23.45) degrees and the fact the Earth's north end was tipped as far toward the sun as it gets about 2 weeks ago is the cause of the heat; more direct sun for a longer period of daylight. That direct sunlight has less atmosphere to shine through and the northern end's tilt allows morning and evening light to shine over the top of the planet and keep the the days longer. The southern hemisphere, currently tipped away from the sun, has low angled light for shorter stretches with the earth blocking the morning and evening light.
So does that mean it gets colder in the southern hemisphere because they are tipped away AND farther from the sun (and hotter in the southern summer when the tilt and closer distance combine for a potential opposite effect)? Hard to tell for certain, there's a lot more water down south than up north and water moderates temperatures, whether hot or cold. And, the land mass at our southern end, Antarctica, has so much ice piled on it, which adds altitude making things colder still, that it's hard to say with scientific certainty. The coldest temps on earth have been recorded in Antarctica during the perennial dark of their winter.
With Hurricane Arthur, earth's natural heat dispersal device, bearing down on the Carolina coasts, being far from the sun is probably not on a lot of folks' mind. But, here we are, as far from our star as we'll get this year but dealing with it's heat nonetheless. Enjoy your Aphelion, because it is only...today on Earth.
Earth's tilt, slowly shifting between 22 and 24 degrees (another possible factor in the comings and goings of ice sheets) with respect to the plane of our orbit around the sun, is the reason it's cooking hot on July 3rd in central Va. Our current tilt of 23 1/2 (actually 23.45) degrees and the fact the Earth's north end was tipped as far toward the sun as it gets about 2 weeks ago is the cause of the heat; more direct sun for a longer period of daylight. That direct sunlight has less atmosphere to shine through and the northern end's tilt allows morning and evening light to shine over the top of the planet and keep the the days longer. The southern hemisphere, currently tipped away from the sun, has low angled light for shorter stretches with the earth blocking the morning and evening light.
So does that mean it gets colder in the southern hemisphere because they are tipped away AND farther from the sun (and hotter in the southern summer when the tilt and closer distance combine for a potential opposite effect)? Hard to tell for certain, there's a lot more water down south than up north and water moderates temperatures, whether hot or cold. And, the land mass at our southern end, Antarctica, has so much ice piled on it, which adds altitude making things colder still, that it's hard to say with scientific certainty. The coldest temps on earth have been recorded in Antarctica during the perennial dark of their winter.
With Hurricane Arthur, earth's natural heat dispersal device, bearing down on the Carolina coasts, being far from the sun is probably not on a lot of folks' mind. But, here we are, as far from our star as we'll get this year but dealing with it's heat nonetheless. Enjoy your Aphelion, because it is only...today on Earth.
Wednesday, June 18, 2014
3 Planets and a Solstice
Saturn, Mars and Jupiter remain the brightest object in the evening sky at the late dusk of midsummer days. Saturn, golden in the south at dark, has moved about half way between Virgo's Spica and the heart of the Scorpion, Antares and that puts it right in the between the left and right claws of Libra. The Romans, in a moment of balance, removed Scorpio's claws and invented Libra, the scales, showing the balance of justice in their system. The names right and left claw remain (the left, Zubenelgenubi is a really fun word to say, but then Zubeneschamali is fun, too) revealing their history.
Mars continues to dim as we pull away from our rusty neighbor. It will stand still with respect to the stars on the solstice and then begin moving east through Libra and sidle back up with Spica. This is the last month for good looks at Mars for quite awhile.
Jupiter's viewing days are fading every day as we move through June. It sinks lower and lower into the west with each day and will be hard to spot by month's end. The king of the planets will be at conjunction with Earth on July 24, behind the sun, emerging as a morning star for late summer and fall.
Venus is still the brightest object in the dawn sky (but with summer's long days you have to be up early) but is pulling away from earth and while gibbous in a scope is shrinking in size and brightness.
Tomorrow is the last quarter moon (look for it in the morning sky) at 2:39pm, to be precise. The waning crescent will be just below Venus on the morning of the 24th for early risers.
Earth, while drifting toward its farthest point from the sun, will have its northern axis tipped as far as it can get toward our nearby star at 6:51am EDT on the 21st, the summer solstice. Farther away and summer??? It's the tilt not the distance that creates the heat of the hot season; more hours of direct sunlight is the summer. Stay cool, it's cooking out there, Today On Earth.
Mars continues to dim as we pull away from our rusty neighbor. It will stand still with respect to the stars on the solstice and then begin moving east through Libra and sidle back up with Spica. This is the last month for good looks at Mars for quite awhile.
Jupiter's viewing days are fading every day as we move through June. It sinks lower and lower into the west with each day and will be hard to spot by month's end. The king of the planets will be at conjunction with Earth on July 24, behind the sun, emerging as a morning star for late summer and fall.
Venus is still the brightest object in the dawn sky (but with summer's long days you have to be up early) but is pulling away from earth and while gibbous in a scope is shrinking in size and brightness.
Tomorrow is the last quarter moon (look for it in the morning sky) at 2:39pm, to be precise. The waning crescent will be just below Venus on the morning of the 24th for early risers.
Earth, while drifting toward its farthest point from the sun, will have its northern axis tipped as far as it can get toward our nearby star at 6:51am EDT on the 21st, the summer solstice. Farther away and summer??? It's the tilt not the distance that creates the heat of the hot season; more hours of direct sunlight is the summer. Stay cool, it's cooking out there, Today On Earth.
Thursday, January 30, 2014
Venus Rules the Dawn
Venus has now pulled far enough away from Earth to be The Morning Star and incredibly bright in the hour or two before sunrise. Mars sits reddish above Spica high in the southwest, Saturn, golden, high in the south but Venus catches your eye; it's the morning star and brilliant.
Jupiter is the evening (and night) star, outshining the many bright stars in the winter evening sky and with the moon new today (4:39pm) has little competition for brightest after dark. As the moon begins to wax - likely not easily visible until Sunday as a thin crescent- Jupiter rules the sky after dark.
It's cold, but the sky is spectacular this winter, so put on the layers and check it out, Today on Earth.
Jupiter is the evening (and night) star, outshining the many bright stars in the winter evening sky and with the moon new today (4:39pm) has little competition for brightest after dark. As the moon begins to wax - likely not easily visible until Sunday as a thin crescent- Jupiter rules the sky after dark.
It's cold, but the sky is spectacular this winter, so put on the layers and check it out, Today on Earth.
Thursday, January 23, 2014
Waning Through the Planets
As the Moon and January wane, the planets on the morning side of Earth each get a chance to shine brightly near our only natural satellite. The last two, very cold, dawns have had the moon on either side of Mars as our planet catches up with our rusty surfaced neighbor. The star just below the moon this morning was Spica, far and away the brightest star in Virgo. Saturday morning will find the moon within a degree or two of the gorgeous ringing world, Saturn. The next two mornings, the thinning crescent will slide above Scorpio, with its bright, red heart, Antares. Antares means "rival of Mars", comparing it's color to Mars will show you why. As the moon gets closer to completing its moonthly orbit of Earth it will be near the newly risen morning star, Venus. The thin crescent will be upper right of Venus on the morning of the 28 and lower left of planet on the 29th. After that, the moon will pass between the Earth and Sun, lined up directly between the two just past 4:30pm on January 30th, the new moon.
Jupiter and the bright stars of winter dominate the evening winter sky. Tonight around 7pm all four Galilean moons will be visible, two on each side of the giant gas world. In the cold, (maybe) clear air they should be easy to spot in even binoculars. The moonless sky and a dark location should also make it easy to see the winter portion of our galaxy, the appropriately named, Milky Way.
Bundle up and check out the sky, tonight on Earth.
Jupiter and the bright stars of winter dominate the evening winter sky. Tonight around 7pm all four Galilean moons will be visible, two on each side of the giant gas world. In the cold, (maybe) clear air they should be easy to spot in even binoculars. The moonless sky and a dark location should also make it easy to see the winter portion of our galaxy, the appropriately named, Milky Way.
Bundle up and check out the sky, tonight on Earth.
Saturday, January 11, 2014
Venus Is Gone, Jupiter Rules
The long run of Venus as the evening star, from late summer until today, is over. Venus is at inferior conjunction today, about 5 hours ago, and between Earth and the sun. It's about 5 degrees above the sun at conjunction but less than that at sunset today for North America so serious telescope skills will be needed to spot its ultra thin crescent. Waiting a few days will allow our planetary neighbor to pull away from Earth and make it increasingly easy to spot in the morning sky. By month's end, Venus will be the Morning Star and will continue to star in that role for the winter and spring. It will have a lovely pairing with a thin, waning crescent moon this month on the mornings of the 28th and 29th.
The dominant player in the night sky is now Jupiter, truly the king of the planets these days. Jupiter was at opposition on the 5th and directly behind the Earth so that as we turn away from the winter sun we turn toward Jupiter, low in the east but rising rapidly and now up all night long. The nearly full moon will be just right of Jupiter on the 14th and the actual full moon (@ 11:52 EST) below the giant planet on the next night. As the moon begins to wane beyond that point and the sky return to darker times, check out Jupiter in binoculars or a small scope and see if you can spot any of the Galilean moons; they are the little dots beside Jupiter. The two bright stars to the east of Jupiter are the heads of Gemini, the twins, Castor and Pollux. See if you can notice their color difference.
The bright stars of winter are now in prime viewing position as the sky darkens. Orion dominates the southeastern sky at dark with it's 3 belt stars making it easy to spot. Once you spot the belt, notice it points up toward a reddish orange star, Aldebaran, the eye of Taurus, the bull. In the opposite direction, the belt stars point down toward, Sirius, the dog star and brightest star we can see from Earth - it's close, only 8+ light years from us. Sirius is hotter and brighter than our sun and noticeably blue-white compared to Aldebaran's rusty hue. Other colorful stars of winter are in Orion: Betelgeuse, the hunter's right shoulder is a red super giant and quite red while the hunter's left knee, Rigel is a sparkly blue-white, much like Sirius. Connecting Sirius, Rigel and Aldebaran puts 1/3 of the Winter Hexagon into place; moving above Aldebaran and up to bright Capella then east to the two twins of Gemini and then down to Procyon, the little dog, links the hexagon and encloses Orion. As a bonus, Jupiter is in the hexagon right now and obviously brighter than any of the stars.
Mercury makes a brief appearance in the evening sky for late January, and is just left of a very thin waxing crescent moon on the 31st. The fast moving messenger planet will catch Earth in February and come out as a morning star by the end of that short month. Never terribly bright or far from the sun, Mercury is always a tough spot whether in the evening or morning sky.
Saturn is not up until well after midnight but it's golden color and lack of twinkle make it a dominant "star" for early risers and easy to spot in Libra. The amazing rings are tipped nicely toward Earth and always a delight to see in even a small scope. Might be worth getting up early to see but we will catch up with the ringed world as the year goes on and it will return to the evening sky.
Mars, hanging with Spica in Virgo, is also a middle of the night "star" for the winter. Earth will continue to close in on our next neighbor out in the planet line-up and the rust surface will be easier to view as we tilt our way towards spring. Mars will dance closely with Spica, the dominant or Alpha star in Virgo, throughout the winter and spring and even into the summer. Mars is redder and slightly brighter than Spica.
The rain and clouds will move on and the clear, cold sky of winter will once again reveal the bright, sparkling stars of the cold season. If not tonight, sometime soon, bundle up and check out the universe around you. I hope your seeing is fine, today on Earth.
The dominant player in the night sky is now Jupiter, truly the king of the planets these days. Jupiter was at opposition on the 5th and directly behind the Earth so that as we turn away from the winter sun we turn toward Jupiter, low in the east but rising rapidly and now up all night long. The nearly full moon will be just right of Jupiter on the 14th and the actual full moon (@ 11:52 EST) below the giant planet on the next night. As the moon begins to wane beyond that point and the sky return to darker times, check out Jupiter in binoculars or a small scope and see if you can spot any of the Galilean moons; they are the little dots beside Jupiter. The two bright stars to the east of Jupiter are the heads of Gemini, the twins, Castor and Pollux. See if you can notice their color difference.
The bright stars of winter are now in prime viewing position as the sky darkens. Orion dominates the southeastern sky at dark with it's 3 belt stars making it easy to spot. Once you spot the belt, notice it points up toward a reddish orange star, Aldebaran, the eye of Taurus, the bull. In the opposite direction, the belt stars point down toward, Sirius, the dog star and brightest star we can see from Earth - it's close, only 8+ light years from us. Sirius is hotter and brighter than our sun and noticeably blue-white compared to Aldebaran's rusty hue. Other colorful stars of winter are in Orion: Betelgeuse, the hunter's right shoulder is a red super giant and quite red while the hunter's left knee, Rigel is a sparkly blue-white, much like Sirius. Connecting Sirius, Rigel and Aldebaran puts 1/3 of the Winter Hexagon into place; moving above Aldebaran and up to bright Capella then east to the two twins of Gemini and then down to Procyon, the little dog, links the hexagon and encloses Orion. As a bonus, Jupiter is in the hexagon right now and obviously brighter than any of the stars.
Mercury makes a brief appearance in the evening sky for late January, and is just left of a very thin waxing crescent moon on the 31st. The fast moving messenger planet will catch Earth in February and come out as a morning star by the end of that short month. Never terribly bright or far from the sun, Mercury is always a tough spot whether in the evening or morning sky.
Saturn is not up until well after midnight but it's golden color and lack of twinkle make it a dominant "star" for early risers and easy to spot in Libra. The amazing rings are tipped nicely toward Earth and always a delight to see in even a small scope. Might be worth getting up early to see but we will catch up with the ringed world as the year goes on and it will return to the evening sky.
Mars, hanging with Spica in Virgo, is also a middle of the night "star" for the winter. Earth will continue to close in on our next neighbor out in the planet line-up and the rust surface will be easier to view as we tilt our way towards spring. Mars will dance closely with Spica, the dominant or Alpha star in Virgo, throughout the winter and spring and even into the summer. Mars is redder and slightly brighter than Spica.
The rain and clouds will move on and the clear, cold sky of winter will once again reveal the bright, sparkling stars of the cold season. If not tonight, sometime soon, bundle up and check out the universe around you. I hope your seeing is fine, today on Earth.
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