Posts Tagged ‘Telescope’

12/07/2021 – Ephemeris – This is the best week to view Comet Leonard

December 7, 2021 Comments off

This is Bob Moler with Ephemeris for Tuesday, December 7th. Today the Sun will be up for 8 hours and 55 minutes, setting at 5:02, and it will rise tomorrow at 8:07. The Moon, halfway from new to first quarter, will set at 8:43 this evening.

The evening sky between 5:45 and 7 pm will feature Venus, the crescent Moon, with dim Saturn above it and Jupiter all in the southwestern sky. Saturn will appear dim, only in the early part of that period, due to bright twilight. Saturn is about midway between Venus and Jupiter. In the morning sky, Comet Leonard continues to fall inward toward the Sun. It’s passing relatively close to the Earth, now about 29 million miles. It will pass its closest to on Sunday at about 21 million miles, at which time we’ll have a hard time spotting it in morning twilight. Comet Leonard will stay barely bright enough to spot in dark skies by really sharp-eyed observers without binoculars or a telescope. The rest of us will need optical aid.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.


Comet Leonard finder 12/08/21 6:30 am

Comet Leonard (C/2021 A1) finder chart for 6:30 am, December 8, 2021. The comet’s tail may not be visible visually. The comet’s head, what astronomers call a coma, may appear as a large fuzzy spot. At that time it will be 26.7 million miles away, and will come within 21.7 million miles at its closest to us on the 12th. Created using Stellarium.

Comet Leonard (C/2021 A1) in the morning

Comet Leonard’s positions at 6:30 am on the dates indicated. The labels are Month-Day Total Magnitude. The star’s position relative to the horizon and the position of Mars are for November 27th. The star field will be shifting to the upper right each morning at 6:30 from the November 27th date at 6:30. Comets always appear dimmer than their magnitude suggests because they are extended objects, not points like stars. Also, comet magnitudes can be unpredictable. Created using Cartes du Ciel (Sky Charts). I’ve reversed the colors from previous printings of this image. Reprinted from my article in the Stellar Sentinel, the newsletter for the Grand Traverse Astronomical Society.

03/17/2014 – Ephemeris – When Ireland had the world’s largest telescope

March 17, 2014 Comments off

Ephemeris for St. Patrick’s Day, Monday, March 17th.  The sun will rise at 7:51.  It’ll be up for 11 hours and 59 minutes, setting at 7:51.   The moon, 1 day past full, will rise at 9:11 this evening.

In the 19th century Ireland laid claim to having the largest telescope.  It was a reflecting telescope with a mirror diameter of 72 inches.  It was built by William Parsons the Third Earl of Rosse.  The base of the telescope tube rested in a pit between two massive walls and could only look in a north-south direction.  It saw first usage in 1847.  The telescope was called the Leviathan of Parsonstown, and was in use until 1890.  Mirrors in those days was made of a silvery alloy called speculum.  Two mirrors were used alternately because speculum tarnished.  The mirror not in use would have to be re-polished and swapped in from time to time.  It was the largest telescope until the 100 inch at Mt. Wilson was put in service in 1917.

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


Leviathan of Parsonstown

The 72 inch Leviathan of Parsonstown. source:

12/28/2012 – Ephemeris – Using that new telescope

December 28, 2012 Comments off

Ephemeris for Friday, December 28th.  The sun will rise at 8:18.  It’ll be up for 8 hours and 51 minutes, setting at 5:09.   The moon, at full today, will rise at 5:48 this evening.

If you gotten a new telescope for Christmas, I’ve got a few tips.  Always start out using your lowest power eyepiece.  It has the largest field of view to help you find what you want.  Once found you may use a higher power eyepiece.  Higher powers may make the image larger, but will not make it sharper.  The wider the telescope the sharper the image, and the higher powers that can be used.  But note that amateur astronomers use their lowest power 90 percent of the time.  The images are sharper and brighter.  And besides most things in the sky don’t need that much magnification.  We mostly need to make them brighter.  That’s why telescopes are sometimes called light buckets.  Good telescope companions are computer programs that show the sky and books on observing.

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

Addendum – Links for more information on telescopes and observing

Advice for First Time Telescope Buyers  by Joe Roberts.  It’s part of his Amateur Astronomers Notebook, whose link is at the top of the page.

Stargazing Basics from Sky and Telescope magazine.

Equipment How To from Astronomy magazine.

Your local astronomy club:  In the Grand Traverse Area (Grand Traverse Astronomical Society) which meets at 8 p.m. on the first Friday of the month.
Also check out both Sky and Telescope and Astronomy web sites above for links to other astronomy clubs.  They are all welcoming of beginners and a great source of telescope expertise.

01/05/2012 – Ephemeris – Viewing planets with that new telescope

January 5, 2012 Comments off

Thursday, January 5th.  The sun will rise at 8:19.  It’ll be up for 8 hours
and 57 minutes, setting at 5:16.   The moon, half way from first quarter to full, will set at 5:59 tomorrow morning.

Trying out that new Christmas telescope can be challenging on cold winter nights.  Set it up indoors first and get used to it.  The moon and planets are the easiest targets for the new telescope owner.  Locate the moon first if it’s out as it is tonight and make sure that small telescope or reflex finder that pots a red dot on the object is aligned with the telescope.  Then you can go off and locate the planets.  Venus is nice and bright in the southwest early in the evening.  A telescope will show a tiny nearly circular orb.  But wait a couple of months and it will become a large crescent.  Jupiter is always a great sight with its four moon shuttling from one side to the other of the planet from night to night.  And don’t forget Jupiter itself with its cloud bands.

* Times, as always are for the Traverse City/Interlochen area of Michigan.

01/02/2012 – Ephemeris – The moon and Jupiter and telescope tips

January 2, 2012 Comments off

Monday, January 2nd 2012.  The sun will rise at 8:19.  It’ll be up for 8 hours and 54 minutes, setting at 5:13.   The moon, 1 day past first quarter, will set at 3:04 tomorrow morning.

Tonight the bright planet Jupiter will appear below the moon.  This is a great time to try out that new telescope or binoculars, or dig that old one out of the closet or attic.  With a telescope use the lowest power to locate the moon and get an overview.  The bright southern part of the moon, which may appear at the top of the image, because telescopes normally invert the image is heavily cratered.  The other part has several dark nearly flat structures called seas.  These are really huge craters that caused the internal lava to well up, making the smooth floors. Recently some astronomers hypothesized that a second moon was created with ours and that it crashed into our moon creating the lunar seas.

* Times, as always are for the Traverse City/Interlochen area of Michigan.


Jupiter appears below moon Jan 2, 2012 9 p.m. Created using Stellarium.

Jupiter appears below moon Jan 2, 2012 9 p.m. Created using Stellarium.

10/13/11 – Ephemeris – Jupiter viewing tips

October 13, 2011 Comments off

Thursday, October 13th.  The sun will rise at 7:54.  It’ll be up for 11 hours and 7 minutes, setting at 7:01.   The moon, 2 days past full, will rise at 7:29 this evening.

Jupiter is now rising before 8 p.m. in the east northeast.   You’ll have to wait  a couple of hours after it rises for good telescopic views of it.  That was my problem in my youth with my first telescope.  I was viewing Jupiter low on the horizon when it was just coming into the evening sky.  I just couldn’t wait until it rose higher.  The thick atmosphere of the earth I was looking through to see Jupiter washed out the planetary details of its cloud bands and Great Red Spot.  So wait for later in the evening or wait a month or so until Jupiter is higher in the sky to get the best views of Jupiter in a telescope.  Jupiter will be closest to the earth on the 29th of this month when it will be in opposition from the sun, rising at sunset and setting at sunrise.

Categories: Jupiter, Observing Tags: ,