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Episode 1 - Magnitudes and
The Painted Globe

(Pawling Public Radio 103.7 FM)

Welcome to The Astronomical Almanac.
I am your host - Bob Antol. I am a local astronomer in the Pawling area (Poughquag specifically), with a passion for all things astronomical.

Astronomy is the branch of science that deals with celestial objects, space, and the physical universe as a whole. This show, The Astronomical Almanac, will make you more comfortable with these concepts so you will be able to recognize, grasp and appreciate the universe around us.

This is the The Astronomical Almanac on WPWL - Pawling Public Radio - 103.7 FM - Pawling, New York.
And today's episode is entitled Magnitudes and The Painted Globe.


Old Business



  >   The first segment of the program is something I call Old Business. This will be devoted to answering any questions from the previous episodes or to correct anything I may have said in error.

The Astronomical Almanac will have the following format:

  1. Old Business - this segment here.
  2. Expanding Your Astronomical Vocabulary - devoted to defining astronomical terms.
  3. What's Up in the Sky This Week? - from planets to meteor showers to the space station and more!
  4. Astronomical Curiosities - exploring unique aspects of the world of astronomy.
  5. Did You Know? - a fun-filled trivia section.
  6. The Buffer Zone - personal recollections from my life as an amateur astronomer.

  <   This concludes the Old Business portion of the program. Next up ... Expanding Your Astronomical Vocabulary ...


Expanding Your Astronomical Vocabulary


Magnitudes


  >   Each week, a term (or two) will be defined laying the groundwork for a more general understanding of astronomy. This week, in Expanding Your Astronomical Vocabulary, I will be discussing ...

Magnitude describes the brightness of stars with a scale built on a historical base.

Hipparchus (190 - 120 BC) (developed trigonometry) said that the brightest stars in the sky were "of the first magnitude". The next brightest stars were "of the second magnitude". And so forth. The faintest stars visible to the naked eye were "of the sixth magnitude".

In the mid-19th century, measurements were done to show that a difference of 5 magnitudes corresponded to a factor of about 100 in brightness.

However, some stars are actually brighter than the initial scale of 1, 2, 3, ..., 6. These stars were given magnitudes of 0 or even -1.

The magnitude scale:

Differences
in Magnitudes
Factor
in Brightness
1 mag 2.512 times
2 mag 6.31 times
3 mag 15.85 times
4 mag 39.81 times
5 mag 100 times
6 mag 251 times
7 mag 631 times
8 mag 1,585 times
9 mag 3,981 times
10 mag 10,000 times
15 mag 1,000,000 times

The apparent visual magnitude list:

Apparent
Visual Magnitude
Object
-26.74 Sun
-13 Full Moon
-6 ISS
-5 Venus
-3 Jupiter & Mars
-2 Mercury
-1.46 (1) Sirius
-0.74 (2) Canopus
-0.27 (3) Rigil Kentaurus (Alpha Centauri AB)
-0.05 (4) Arcturus
0.03 (5) Vega
0.08 (6) Capella

The absolute magnitude list (each object exactly 10 parsecs [32.6 light years] away):

Absolute
Magnitude
Object Apparent
Visual Magnitude
-12.5 RMC 136a1 (a Wolf-Rayet star located in the central Tarantual Nebula 163,000 light years from Earth) 12.23
-12.2 M33-013406.63 (in the Triangulum Galaxy) 13.10
-12.16 WR 25 (in Carina Nebula 7,500 light years from Earth) 8.80

  <   This concludes the Expanding Your Astronomical Vocabulary portion of the program. Next up ... What's Up in the Sky This Week ...


What's Up in the Sky This Week


  >   In this next segment of the program (What's Up in the Sky This Week), I will highlight events in the sky that are of interest to the average person. First up ...

  • Moon Phase (using https://www.timeanddate.com/moon/phases/@5132148)

    Date Name U.S. East UTC Description
    Oct 5 Harvest Moon 2:40 PM 19:40 The moonrise comes soon after sunset. This results in an abundance of bright moonlight early in the evening, which was a traditional aide to farmers and crews harvesting their summer-grown crops. October's Moon is also known as the Hunter's Moon, Travel Moon and the Dying Moon.
    Month Southern Hemisphere Name
    October Egg Moon, Fish Moon, Seed Moon, Pink Moon, Waking Moon

  • Evening sky highlights
    N/A No evening highlights

  • Morning sky highlights
    5 Oct 2017 Mars is 0.2 degrees lower right of Venus

  • Upcoming meteor showers
    9 Oct Draconid meteor shower (class III variable shower)
    22 Oct Orionid meteor shower (class I major shower)

    2017 Major Meteor Showers (Class I)

    Shower Activity Period Maximum Radiant Velocity r Max. Time Moon
    Date S. L. R.A. Dec. km/s ZHR
    Orionids (ORI) Aug 25-Nov 19 Oct 22 208.9 06:24 +15.5 67.1 2.5 15 0500 03

  <   This concludes the What's Up in the Sky This Week portion of the program. Next up ... Astronomical Curiosities ...


Astronomical Curiosities


The Painted Globe


  >   In this segment, called Astronomical Curiosities, I will explore a unique and different aspect of the world of astronomy. Today's curiosity is ...

This is the The Astronomical Almanac on WPWL - Pawling Public Radio - 103.7 FM - Pawling, New York ... streaming live at pawlingpublicradio.org.

Discuss the following:

    The Painted Globe Solar Eclipse Lunar Eclipse

Eclipses in 2017:

  • February 10th (penumbral lunar eclipse for Eastern North America)
  • February 26th (annular solar eclipse for Southern South America and Africa)
  • August 7th (partial lunar eclipse for Asia)
  • August 21st (total solar eclipse for North America) (my images are here)

Eclipses in 2018:

Upcoming Eclipses for Pawling / Poughquag:

Eclipses For Your City (https://www.timeanddate.com/eclipse/)

The Number of Eclipses in a Year

  • The least possible number of eclipses in a year is 4.
    1. 2 solar
    2. 2 lunar
  • The greatest possible number of eclipses in a year is 7.
    1. 5 solar, 2 lunar
    2. 4 solar, 3 lunar
    3. 3 solar, 4 lunar
    4. 2 solar, 5 lunar

In the years with 5 solar eclipses, this is rarely reached. Between the years 600 BC and 3400 AD, there are only 14 such 'rich' years (last one 1935, next one 2206).
In a calendar year, there may be 3 total lunar eclipses. Between the years 0 AD and 3200 AD, there are only 17 such years (last one 1982, next one 2485).

Now, on to the "painting"!

It takes 20 centuries to paint more than 99 percent of the globe; and it takes 30 centuries to paint more than 99.9 percent.

To paint the entire globe, it would take 4600 years (1400 BC - 3158 AD).

And for those interested, the North and South poles were or will be painted:

  • North Pole: July 6th, 1815 (my North Pole Journals are here)
  • South Pole: January 16th, 2094

  <   This concludes the Astronomical Curiosities portion of the program. Next up ... Did You Know? ...


Did You Know?


  >   This segment of the program will be devoted to little bits of trivia that can be shared at parties, family get-togethers, reunions. Hey, the next time you are at a bar and there is a lull in the conversation, simply yell out Did You Know ... and share the following!

Telescope Time Machine: Light from distant stars and galaxies takes so long to reach us that we are actually seeing these objects as they appeared in the past. As we look up at the sky, we are really looking back in time. For example, the Sun's light takes almost 8.5 minutes to travel to Earth, so we see the Sun as it looked 8.5 minutes ago. The nearest star to us, Proxima Centauri, is 4.2 light-years away, so it appears as it was 4.2 years ago. The nearest galaxy is 2.5 million light-years away, and it looks as it did when our australopithecus hominid ancestors walked the planet. The farther away something is, the further back in time it appears.

  <   This concludes the Did You Know? portion of the program. Next up ... The Buffer Zone ...


The Buffer Zone


  >   If there is still time left in the program, this segment (The Buffer Zone) will be devoted to 'personal recollections' of the things that initially got me interested in astronomy.

The Astronomical Almanac can be found on the web at http://www.stargate4173.com/wpwl/.

You will be able to see:

  • The format of the show
  • Links to the music from the show
  • Links to the notes for each episode
  • My bio

  <   This concludes the The Buffer Zone portion of the program.

This has been The Astronomical Almanac
on WPWL - Pawling Public Radio - 103.7 FM - Pawling, New York.
I have been your host - Bob Antol.
I hope you enjoyed today's show and are a little more comfortable with the topics I discussed so you can now more easily recognize, grasp and appreciate the universe around us.
On next week's show, the episode will be entitled Celestial Coordinates and Different Types of Telescopes.

Clear skies ... and don't forget ... to look up!

copyright © 2017 Robert A. Antol