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Posts Tagged ‘Pluto’

10/29/2015 – Ephemeris – The blue skies of Pluto

October 29, 2015 Comments off

Ephemeris for Thursday, October 29th.  The Sun will rise at 8:16.  It’ll be up for 10 hours and 19 minutes, setting at 6:36.   The Moon, 2 days past full, will rise at 8:40 this evening.

Images from the New Horizons spacecraft are streaming back slowly.  It’s like trying to download a modern megapixel camera image using a thousand to two thousand bits per second telephone modem back in the ’90s.  That’s why the images are dribbling out.  They are released each Thursday or Friday.  One of the last images was a colored image of the ring of atmosphere of Pluto backlit by the Sun, showing that the dwarf planet had a blue sky.  The reason is still debated because there appear to be minute particles thought to be tholins in Pluto’s atmosphere.  These would be colored brown or red.  However they seen to preferentially scatter blue light like the nitrogen molecules in our atmosphere.

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

Addendum

Pluto in Silhouette

Pluto seen in silhouette, backlit by the Sun in color. Released October 10, 2015 by NASA/JHUAPL/SwRI

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10/19/2015 – Ephemeris – Where did the Moon come from?

October 19, 2015 Comments off

Ephemeris for Monday, October 19th.  The Sun will rise at 8:03.  It’ll be up for 10 hours and 48 minutes, setting at 6:51.   The Moon, 1 day before first quarter, will set at 11:51 this evening.

Only two planets in the solar system have moons at least a quarter the size of the planet they orbit:  The Earth and Pluto.  The Moon is a bit more than a quarter the Earths diameter while Pluto’s moon Charon is half its size.  Probably in the early days of the solar system, some four and a half billion years ago collisions were rather common.  It is thought by many planetary scientists that a Mars sized protoplanet collided with the proto-earth with a glancing blow to rip off much of the Earth’s crust, thrust it into orbit where it coalesced into the Moon.  It seems that Pluto’s Charon may have been formed much the same way.  Some thing the varying axial tilts of the planets may have been caused the same way by smaller objects.

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

Addendum

Collision spawning the Moon

The hypothetical collision of a Mars sized body with the young Earth. Credit: Joe Tucciarone via NASA

Breaking News

Robert Farquhar the man behind the ISEE-3 spacecraft, the first to hang out at the Earth-Sun L1 point between the Earth and the Sun back in 1978 passed away yesterday.  In 1982 he “stole” the spacecraft and through an amazing number of maneuvers using very little fuel managed to send it through the tail of Comet Gicobini-Zinner ahead of the fleet of spacecraft then aimed at Halley’s Comet.  Last year when the then renamed spacecraft ICE approached the Earth, he hatched a plan to return the spacecraft to its L1 position.  Unfortunately apparently there was not enough fuel pressure to complete the burns necessary for the task.  I’ll have a program on Robert Farquhar next Monday.

10/02/2015 – Ephemeris – I talk about Pluto and New Horizons tonight

October 2, 2015 Comments off

Ephemeris for Friday, October 2nd.  The Sun will rise at 7:41.  It’ll be up for 11 hours and 40 minutes, setting at 7:21.   The Moon, 2 days before last quarter, will rise at 10:53 this evening.

This evening yours truly will be reviewing the results so far from the New Horizons spacecraft and its close encounter with Pluto and its moons July 14th. This will be at the Grand Traverse Astronomical Society meeting at Northwestern Michigan College’s Rogers Observatory at 8 p.m.  If you’ve not been keeping up with the releases of photos of Pluto and its moons be prepared to be amazed by the beauty of this frozen but apparently active world.  Afterward from 9 p.m. there will be time to view the wonders of the autumn skies if it’s clear.  If not there will be guided tour of the autumn skies via computer simulation.  The observatory is located south of Traverse City on Birmley Road between Garfield and Keystone Roads.

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

Addendum

Charon in color

Latest high resolution color image of Charon released yesterday. Credit: NASA/JHUAPL/SwRI.

09/29/2015 – Ephemeris – New Horizons is now downloading some really cool pictures to Earth

September 29, 2015 Comments off

Ephemeris for Tuesday, September 29th.  The Sun will rise at 7:38.  It’ll be up for 11 hours and 49 minutes, setting at 7:27.   The Moon, 2 days past full, will rise at 8:38 this evening.

Two and a half months ago the New Horizons spacecraft flew past Pluto, spending the day incommunicado, not wasting any time sending anything back to the Earth.  Starting the next day came the flood of data including some highly compressed images.  Starting Labor Day weekend the high-resolution, uncompressed images started to come down at one to two thousand bits per second.  At that rate a 4 megapixel monochromatic image might take 36 hours to download.  Now every Thursday or Friday the New Horizons Team puts several new processed images on the NASA and Johns Hopkins Applied Physics Laboratory websites, along with explanations of what is in the images and the questions they raise.

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

Addendum

Oblique view of Pluto

This image, taken just 15 minutes after the New Horizons spacecraft flew its closest to Pluto shows a low angle shot of the lands the spacecraft saw really close up. Check out too the many layers of the atmosphere. Credit: NASA/JHUAPL.  Click on the image to enlarge.

I’ll be exploring this and the other amazing photos and other results from New Horizons this Friday at the Grand Traverse Astronomical Society meeting at 8 p.m. at Northwestern Michigan College’s Rogers Observatory south of Traverse City on Birmley Road.

08/25/2015 – Ephemeris – Waiting for more images from New Horizons

August 25, 2015 Comments off

Ephemeris for Tuesday, August 25th.  The Sun rises at 6:56.  It’ll be up for 13 hours and 35 minutes, setting at 8:32.   The Moon, 3 days past first quarter, will set at 3:16 tomorrow morning.

The New Horizons team is downloading data now from all the instruments gathered from the encounter with Pluto, but in mid-September the pictures again will be flowing down to Earth.  What was downloaded in the day and a half after close encounter with Pluto were highly compressed images of an area of Pluto and Charon’s surface showing a wider view than we will see later on and in full resolution.  The team is already beginning to name the features that can be seen in sufficient detail.  The International Astronomical Union has decided the types of names for Pluto, Charon and the rest of the Satellites.  Pluto is set aside for explorers, both human and robotic.  Charon, for mythical and fictional space and adventure heroes, vessels and authors.

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

Addendum

Annotated Pluto

Map of Pluto with unofficial place names so far. Credit NASA/JPL. Click to enlarge.

Annotated Charon Map

Map of Charon with unofficial place names so far. Credit NASA/JPL. Click to enlarge.

The International Astronomical Union approves all names of objects off the Earth.  Go to either http://www.iau.org or more specifically http://planetarynames.wr.usgs.gov.

07/30/2015 – Ephemeris – Pluto’s enigmatic atmosphere

July 30, 2015 Comments off

Ephemeris for Thursday, July 30th.  The Sun rises at 6:26.  It’ll be up for 14 hours and 44 minutes, setting at 9:11.   The Moon, 1 day before full, will set at 6:45 tomorrow morning.

The last image released last week from the New Horizons spacecraft was a stunning one.  It was Pluto backlit, showing a glow completely around the planet, the atmosphere, showing layers.  Also when New Horizons went behind the planet and again went behind Charon from the Earth’s point of view.  Beams of radio waves from seven of the antennas of NASA’s Deep Space Network were sent toward Pluto and New Horizons four and a half hours earlier.  The spacecraft turned its antenna toward Earth and listened.  As the radio waves passed through the atmosphere of Pluto they were refracted and distorted giving clues to the state of the atmosphere.  First takeaway is that Pluto’s atmosphere appears to be collapsing with its increasing distance from the Sun.

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

Addendum

Pluto's halo

Looking back at Pluto backlit by the Sun from 1.25 million miles. Credits: NASA/JHUAPL/SwRI.

Click here for more information on the above image.

Alice Data on the atmosphere of Pluto

Data from the Alice ultraviolet instrument when Pluto occulted the Sun. Credits: NASA/JHUAPL/SwRI.

Click here for more information on this Alice observation.

07/28/2015 – Ephemeris – The first close up images of Pluto

July 28, 2015 Comments off

Ephemeris for Tuesday, July 28th.  The Sun rises at 6:24.  It’ll be up for 14 hours and 49 minutes, setting at 9:13.   The Moon, 3 days before full, will set at 4:32 tomorrow morning.

Two weeks ago the New Horizons spacecraft zipped through the Pluto system gathering a wealth of information including a whole host of images.  Due to their large size the images will take some time to be sent back, however some highly compressed images have been returned and yield a tantalizing look at the dwarf planet Pluto and its large moon Charon.  Rather than an apparently dead heavily cratered body, the first images presented a young surface with plains and mountains with nary a crater to be found.  Young is relative, perhaps 100 million years old or so and implied heating where there appears no source to be found… yet.  The first of many mysteries.  And we have 16 months more  of data and images to be returned.

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

Addendum

Ice Mountains

First closeup picture the New Horizon Team showed. Two mile high ice mountains, plains, and interesting terrain, but no craters. A young surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.  Click on image to enlarge.

Sputnik Planum

Sputnik Planum (Plain) next to the ice mountains showing polygons and troughs, some with hills. This is part of Pluto’s “Heath”. Note the rectangular lossy compression artifacts in the image. An uncompressed version will be downlinked later. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.  Click on image to enlarge.