Heads UP! for April 2014
During the night of April 14 – 15, you can see all the sunrises and sunset around the world in one night. After midnight on April 15th, we can see our Moon tinted red and blue by sunlight passing through the dust, clouds and ozone of Earth’s atmosphere at the moment of sunrise or sunset, as seen from the Moon. That’s a lunar eclipse, where the Earth blocks out the Sun and puts the Moon in the Earth’s shadow.
Unlike a solar eclipse, a lunar eclipse can see be seen across half the world at once. This eclipse begins in the eastern daylight time zone at 1:58am before dawn on the 15th, and at the same time across the country, including in the pacific daylight time zone at 10:58pm on the 14th. If you get up for the start of the eclipse, watch for the stars around the Moon become more visible as the Moon darkens.
There is quite a collection of objects near the Moon in the sky that night, with Mars very noticeable nearby, Spica right next to the Moon and two asteroids, Ceres and Vesta, visible in binoculars nearby.
At maximum eclipse, at 3:46am, watch for the variation in light across the Moon as the southern part of the Moon is close to the edge of the earth’s shadow and will look brighter than the northern part of the Moon. The partial eclipse is over by 5:33am, and the sky begins to lighten with the Sun coming up at 6:16am in our area.
If you don’t want to get up ‘in the middle of the night’, set your alarm for a little before 4am and watch the second half of the eclipse, when the line of sunrises and sunsets will move across the Moon from 4:25am to 5:33am. The eclipsed Moon may be low enough in the southwestern sky to be seen from indoors, through a window. This ‘picture window’ eclipse allows viewing from the comfort of home.
Meanwhile, watch this month as the winter constellations, with all their bright stars, appear to rush for the exits, leaving our evening skies for the season, so look early after dark to see them. To take their places, Leo the lion and the Big Dipper head for the overhead this month.
This month is your best chance to view details on Mars. Crank the telescope’s power up as high as the shimmering atmosphere of the Earth will allow. The best nights are when the jet stream is not over your observing site. We pass closest to Mars on the 14th, and Mars is the closest planet to Earth this month, but still not the largest in apparent size.
Jupiter spends most of the evening higher in the sky than Mars, thanks to its location in the northern latitudes of the constellations. It’s 90 degrees away from the Sun in the sky, so when the shadows of its moons are on the planet, the moons are mostly off to one side, giving the view the appearance of depth.
Among the things you can’t see this month is an annular solar eclipse, visible in a small area of a remote part of Antarctica on the 27th. It’ll be a partial eclipse in Australia, if you are going ‘down under’ this month.
Mercury is too close to the Sun to see easily this month, passing in back of the Sun, from Earth’s point of view, on the 26th. Neptune and Uranus are deep in the glare of the Sun.
Venus sits patently waiting, low in the southeast, well to the right of where the Sun will rise. It’s half full (not the same as half-empty) at the start of the month. The phase is easiest to see in a telescope when the sky starts to brighten up.
Saturn, the ringed wonder is still highest in the sky in the wee hours of the morning. It’ll be more conveniently located in the evening sky in May, when it reaches opposition.
Look for Venus and the Moon posing together on the mornings of the 25th and 26th. The Moon also appears startlingly close to Saturn on the 17th.
The International Space Station is visible in dusk from the 4th through the 25th. The recent arrival of the Russian Soyuz capsule brought the station population back up to six. Japan Aerospace Exploration Agency (JAXA) astronaut Koichi Wakata is the station commander, the first Japanese astronaut to command the international outpost.
The highlight of March will be ‘not seeing’ something. The brightest star in Leo the lion, Regulus, will be briefly blotted out by faint asteroid Euigone(1) passing in front of it just after 2am EDT as seen from a narrow band passing over the New York City area. Seeing one of the brightest stars in the sky turn off for up to 14 seconds is a spooky event worth seeing. Timings from many locations of how long Regulus disappears can be used to map the shape of the asteroid. (See http://www.astronomy.com.cn/bbs/thread-223054-1-1.html scroll down for examples) For lots of details, including how to make scientifically useful observations, see http://occultations.org/Regulus2014/.
To see this event, in addition to setting an alarm clock at oh so dark in the morning, you’ll need to make sure you won’t go out at 2am just to find out you can’t see Regulus from where you planned to stand. (Seeing Regulus disappear behind a tree branch or a house definitely does not count!) So, go out some evening earlier that week and see if you can see the tip of the V in Hyades in Taurus around 8 to 8:30pm EDT. (That’s the V above Orion with reddish Aldebaran at the end of one of the arms of the V.) Regulus at 2am will be about a couple of fingerwidths below that spot in the sky, so if you can see that area below the V without obstructions, you should be able to see Regulus from the same spot around the time of the occultation.
Of course, there are many longer-lasting astronomical sights at more reasonable times in March.
The morning sky has a bright spray of planets, with Venus anchoring the scene low in the dawning sky. To its lower left early in the month is Mercury and well to its right is Saturn, and Mars further to the right, giving the early riser up to four planets for inspection.
Mars gets 25% larger this month and looks substantially brighter as we approach for our closest pass in many years in April. Mars rises by the end of evening twilight late in the month, making it more accessible to the prime time observer with a moderate or large telescope.
Saturn, a morning object, gets 5% larger in March, making a great sight even easier to see.
Venus gets smaller but thicker this month, more like a half-moon than a crescent when seen in a telescope during twilight. It’s standing out low in the southeastern dawn sky. Venus is joined by Mercury, which will be hard to spot lower to the left during the first two weeks of March. By the end of the month, Venus is , moving rapidly away from the Earth and gives up its title as the ‘closest planet to Earth’ to Mars.
Early morning astronomy gets a bit easier with the change to daylight time, with sunrise returning to after 7am, a time more typical to early January, but giving us more time for viewing Venus from east-facing train, bus and elevated subway stations on our way to work.
Jupiter is king of the nightime, passing high and bright overhead during prime time. It’s a great time to see the giant planet, with its ‘great red spot’ more prominent this year and four bright moons that occasionally leave their shadows lingering on the planet’s face.
A bit late for Olympic ice dancing, 4Vesta and 1Ceres appear to twizzle across the sky in Virgo, paired up from now through summer. In July they get within one degree of each other in the sky. Use your imagination to ‘see’ NASA’s Dawn spacecraft as its ion engine putters on its way between the two asteroids. You’ll need a good chart of their locations, but it’s great if you can track these two large rocks as they brighten enough to be see in binoculars as they move among the stars of Virgo from week to week.
The International Space Station joins the fun in the morning sky starting on the 11th through the end of the month.
This wouldn’t be an almanac column without noting the equinox occurs at 12:57pm EDT on March 20th. Enjoy!
(1) Erigone is from a Greek myth, so when spoken it’s divided up as e-RIG-on-e, not er-i-gone, even though since it’s making a star disappear, it might be more fun to use the “–gone” version.
The minor adjustments in the NWS thinking for Monday is the timing of snow, perhaps from Midnight through the midday on Monday, otherwise the options in the last post are still in play.
Go to your local forecast from the NWS to get their thoughts on when the snow might fall and when the most of the snow would be……http://forecast.weather.gov/MapClick.php?CityName=Ardsley&state=NY&site=OKX&lat=41.0146&lon=-73.8412#.UxD4B7Rm3IX
Click on your location on the map for the local details.
National Weather Service is noting the models are moving back to a multi-low pressure solution, as opposed to everything phasing together for one big storm. Our forecast depends on a large known uncertainty – what does the model do with a large upper air storm in the western US and when does it send its energy eastward?
Here’s what the NWS says in their NYC Forecast Discussion this morning……
AS A RESULT…THERE IS CURRENTLY NO REASON TO DEPART FROM PREVIOUS
FORECAST OF AT LEAST 8 INCHES OF SNOW ACROSS THE TRI-STATE FROM
SUNDAY NIGHT INTO MONDAY NIGHT. HOWEVER…IF THE TREND CONTINUES
TOWARDS A MORE SUPPRESSED TO THE [South] SOLUTION…THEN LOWER AMOUNTS ARE
POSSIBLE…IT IS STILL CONCEIVABLE THAT THE ENTIRE REGION COULD END
UP GETTING NO SNOW AT ALL – THOUGH HIGHLY UNLIKELY. ANOTHER
POSSIBILITY THAT WOULD LOWER SNOW AMOUNTS OVER SOUTHERN ZONES IS
THAT A WEAKER HIGH BUILDS TO THE N THAN CURRENTLY EXPECTED…THIS
WOULD ALLOW FOR A WINTRY MIX OVER SOUTHERN ZONES…REDUCING AMOUNTS
THERE. THIS ALSO APPEARS UNLIKELY AT THIS TIME. ANOTHER SOLUTION
STILL POSSIBLE IS THAT THERE IS MORE PHASING THAN CURRENTLY
FORECAST…THIS WOULD BRING THE LOWS…OR MORE LIKELY A SINGLE LOW
TRACKING CLOSER TO THE BENCH MARK…THIS WOULD INCREASE QPF AND
SNOWFALL…BUT COULD ALSO BRING THE LOW LEVEL WARM TONGUE OVER
SOUTHERN PORTIONS OF THE AREA…DEPENDING ON THE STRENGTH OF THE
HIGH. THIS IS A MORE REALISTIC POSSIBILITY.
Friday morning will be very cold, even for winter. This is one of the few times, despite the cold winter, when we could set records for low temperatures for Friday and Saturday. Some snow showers with little or no accumulation this weekend.
Scroll down for the story about snow for next week – after the National Weather Service write-up comparing temperatures for the next few days with historical daily temperature records (not all-time lows – we’re well above that).
HERE ARE THE RECORD LOW TEMPERATURES AND FORECASTED LOW TEMPERATURES
FOR FRIDAY…FEBRUARY 28 AND SATURDAY MARCH 1…AND THE RECORD LOW
MAXIMUM TEMPERATURES AND FORECASTED HIGH TEMPERATURES FOR FRIDAY
SITE……..RECORD/YEAR SET…FORECAST LOW
SITE……..RECORD LOW MAX/YEAR SET…FORECAST HIGH
SITE……..RECORD LOW/YEAR SET…FORECAST LOW
Glad you made it down here -
The NWS is telling us that the front coming through this weekend will lay out to our south. The lift of warm air over the front will overshadow us. Combine that with a an area of peak wind in the jet stream to our north will result in trapping a lot of air over us with nowhere to go but up.
That sets up for a storm to develop and pass off our coast.
If the front lays the trap further south, less snow. If the front lays the trap further north, more warm air will decrease snow amounts due to mixing with sleet and rain.
If the trap is sprung, then eight inches or more of snow will happen over the NYC and surrounding area. Less far inland and most near the coast. The snow would start Sunday night and end Monday night.
Stay tuned for updates over the weekend.
The NWS is noting that the very unstable atmosphere with a small but strong upper air wave will give periods of impressive snowfall during Wednesday morning, but is predicting accumulations of 1 to 2 inches total in the locally heavy showers, with most areas getting 1/2 inch total.
Saturday has a cold front bringing the more arctic air into our area with a few snow showers, which might be impressive but not amount to much.
The problem with this front is if it doesn’t go far enough south, when waves of low pressure come along the front, it may drop snow on us if we stay on the north (colder) side of the front for the first half of next week.
After a line of rain – with thunderstorms – lingers over the east coast on Friday, we go for a while without major storms, but a polar low will drive cold air into the midwest and northeast starting by the middle of next week, with the coldest air arriving by the beginning of March.
Look below at the computer forecast map for the northern hemisphere at one kilometer above the surface for Saturday evening MARCH 1st (00Z March 2 on the map); the blue area is the coldest temperatures – look at the area of blue extending from the USA on the lower right back across the North Pole to Siberia.
The solid lines show the wind flow.