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Stupid Internet posts: No, gravity won’t be canceled January 4th.

December 24, 2014 Comments off

Looks like the hoaxsters are at it again.  Seems someone dusted off Sir. Patrick Moore’s April Fool’s joke from long ago and dressed it up as a phony NASA tweet and sent it out 9 days ago.  Supposedly on January 4th, 2015 an alignment of Jupiter and Pluto will cancel gravity on the Earth for a few minutes that day.  Both Newton and Einstein would be ticked off at that.  Neither of their theories of gravity would predict anything so stupid.    Besides Jupiter and Pluto are at nearly opposite parts of the sky.  They don’t align with anything.

Don’t take my word for it as a lowly amateur astronomer.  Check out the (A real astrophysics PhD) Bad Astronomer Phil Plait’s post:  http://www.slate.com/blogs/bad_astronomy/2014/12/24/zero_g_day_nope.html.

Here’s a post from EarthSky with the same sentiments.

However January 4th, 2014 is special.  It’s Perihelion Day, the day of the year the Earth is closest to the Sun.  So break out the sunscreen, especially if you live in the southern hemisphere, where it’s summer now.  The biggest effect we’ll see is that winter is the shortest season for us by a couple of days compared to summer, the longest season.  The Earth moves its fastest in it’s orbit of the Sun at perihelion.

12/24/2014 – Ephemeris – Twas the night before Christmas and only the planets and a comet were stirring

December 24, 2014 Comments off

Ephemeris for Christmas Eve, Wednesday, December 24th.  The sun will rise at 8:17.  It’ll be up for 8 hours and 49 minutes, setting at 5:06.   The moon, 3 days past new, will set at 8:37 this evening.

Twas the night before Christmas and only the planets were stirring.  Venus is low in the southwest shortly after sunset.  It now sets at 6:09 p.m., 63 minutes after the sun.  It will be tough to spot at all.  New Year’s Eve might be a good time to start to see it.  Mars, low in the southwest at 7 p.m. has the Moon just to the right of it tonight.  Mars will set tonight at 8:34 p.m.  Jupiter, which will be our Christmas Star this year will rise in the east at 8:59 p.m.  It’s near the sickle shaped head of Leo.  Jupiter is now moving slowly westward.  This is an effect that happens because the Earth is passing Jupiter, a motion shared by all the planets that baffled the ancients who thought the Earth to be motionless.  Saturn will rise in the east-southeast at 5:34 a.m.

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

Addenda

The Planets tonight

Venus and the Moon

Venus low on the horizon, and the Moon, at 5 30 p.m. on December 24, 2014. Created using Stellarium.

The Moon through Binoculars

The crescent Moon through binoculars, at 5 30 p.m. on December 24, 2014. Created using Stellarium.

Mars and the moon

Mars and the Moon at 7:30 p.m. on December 24, 2014. Created using Stellarium.

Jupiter and the winter constellations

Jupiter and the winter constellations at 11 p.m. on December 24, 2014. Created using Stellarium.

Telescopic Jupiter

Jupiter with three hidden satellites, with only Callisto showing at 11 p.m. on December 24, 2014. See blow by blow of the satellite disappearances below. Created using Stellarium.

Jovian satellite events of the night of December 24-25, 2014

Ganymede starts eclipse (enters Jupiter’s shadow) 6:20 p.m.
Europa starts eclipse 8:27p.m.
Io’s shadow starts crossing Jupiter 9:32 p.m.
Ganymede leaves Jupiter’s shadow 10:00 p.m.
Ganymede starts being occulted by Jupiter 10:11 p.m.
Io’s transit across the face of Jupiter starts 10:29 p.m.
Io’s shadow leaves the face of Jupiter 11:50 p.m.
Io’s transit of Jupiter ends 12:46 a.m.
Europa’s occultation by Jupiter ends 1:10 a.m.
Ganymede’s occultation by Jupiter ends 1:50 a.m.

Note that Europa’s occultation by Jupiter starts before its eclipse ends, so unlike the more distant Ganymede there isn’t an interval of visibility between the two.

Jovian satellite event timings provided by Project Pluto www.projectpluto.com

Saturn

Saturn low in the east-southeast among the constellations of late spring and early summer at 6:30 a.m. on Christmas morning 2014 . Created using Stellarium.

Comet C/2014 Q2 (Lovejoy)

Normally my Ephemeris program deals with celestial objects that are visible to the naked eye.  While Comet Lovejoy will, for a few weeks become brighter than 6th magnitude the normal limit for the unaided human eye, a comet is a diffuse object and always looks dimmer than a star of the same magnitude.  This comet was discovered August 17, 2014 by Australian amateur astronomer Terry Lovejoy.  He has discovered 5 comets.  His most famous find was C/2011 W3 (Lovejoy) that buzzed the Sun and survived becoming a magnificent comet for southern hemisphere observers.

Recently Comet Lovejoy became brighter than expected.  The data for the charts below are from Minor Planet Center and do not include new brightness estimates that include the outburst.  They have the comet reaching magnitude 4.9.  The aerith.net website gives the maximum brightness next month of 4.  (Magnitudes are like golf scores the lower the magnitude the brighter the object).  Each magnitude step is a brightness difference of about 2 and a half times.  To check on the comet go to http://www.aerith.net/comet/weekly/current.html.  Currently Comet Lovejoy is the brightest comet now visible and is the first comet on the list.  Clicking on the comet ‘s name will give you the comet’s page.  The last chart on the page is a chart tracking the comet’s brightness from reports vs. prediction.  That chart predicts a magnitude of 4 just after the first of the year.

Photographs of the comet show a gaseous coma (head) and a very faint ion tail, which may not be visible visually in binoculars and telescopes.  Right now the comet is highest around midnight.

The finder charts below designate the comet by month-day and the predicted magnitude

Comet Lovejoy 12/24/14 to 1/17/15

Comet C/2014 Q2 (Lovejoy) at 11 p.m. at 2 day intervals from tonight 12/24/2014 to 1/17/2015. Created using Cartes du Ceil (Sky Charts).

omet Lovejoy 1/17/15 to 2/12/15

Comet C/2014 Q2 (Lovejoy) at 8 p.m. at 2 day intervals from tonight 1/17/2015 to 2/12/2015. Created using Cartes du Ceil (Sky Charts).

On December 28th Comet Lovejoy will appear to pass the globular cluster M79.

Comet Lovejoy and M79

Comet Lovejoy and M79 a distant globular star cluster, in the constellation of Lepus the hare, will appear together at 11 p.m. December 28th, 2014. Note the that M79 is the unlabeled blue dot in the tail of the comet, next to the head. Created using Cartes du Ceil (Sky Charts).