01/20/2020 Epkemeris Extra – Epheneris will be on a short hiatus

January 20, 2020 2 comments

On January 11th I suffered a stroke. It affected my left side and scrambled my brains a bit.  I’m in Mary Free Bed Rehabilitation at Munson Medical Center in Traverse City, for a bit to get my left side talking better to my brain. I hope to be back in a month or so. Thanks for the messages of concern sent here and to Interlochen Public Radio.

Bob Moler

p.s. Yesterday’s SpaceX Crew Dragon inflight abort test looked pretty cool!

Categories: Ephemeris Extra

01/10/2020 – Ephemeris – Eclipses today and to come

January 10, 2020 1 comment

I usually create these posts on the evening before the Ephemeris program airs on Interlochen Public Radio, though I record and post the audio programs the prior Sunday evening.  Wednesday we learned that my 102 year old mother-in-law Edith DelRaso was back in the hospital wit pneumonia after being released from the hospital for the same complaint This time it was worse.  My daughter, younger granddaughter and I headed south to Grand Rapids.  This lady had outlived all her many siblings, her husband and all but one of his siblings, and two of her three children, including my wife Judy.  She was ready to go.  At about 5:15 p.m. she breathed her last peacefully.  After a couple of hours with the gathered family we headed out to a favorite restaurant.  The weather in the Grand Traverse Area was worsening, so I got talked into staying in GR with my brother and his wife, and to head back today, so I missed posting this last night.  As a sad coincidence my niece’s father-in-law had a massive heart attack and eventually died at about the same time in Detroit. A sad day all around.

On with the show.

Ephemeris for Friday, January 10th. Today the Sun will be up for 9 hours and 2 minutes, setting at 5:21, and it will rise tomorrow at 8:18. The Moon, at full today, will rise at 5:20 this evening.

Later on this afternoon there will be a lunar eclipse, one of 4 this year. All of these are penumbral eclipses where the Moon misses the dark inner shadow of the Earth and skims through the outer partial shadow, where the Sun’s light is only partially obscured by the Earth, showing a slight dusky appearance on the side nearest the dark shadow. Being daytime the Moon will not have rises for use to see it. We will be able to witness the last two. The first of these is early in the morning hours of July 5th and be barely visible, the second will be in the morning hours of November 30th. There will be two solar eclipses, neither of which will be visible here. However, next year there will be a solar eclipse where the Sun will rise partially eclipsed here and we’ll see the last half hour of it.

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

Addendum

Our best penumbral lunar eclipse this year.

Our best penumbral lunar eclipse this year, November 30, 2020. Subtract 5 hours from the UTC contact times to get Eastern Standard Time. Excerpted from a NASA/GSFC graphic by Fred Espenak.

The Sun rises in Eclipse 6/10/21

The Sun will rise in eclipse at 6:05 a.m. June 10, 2021 in the Grand Traverse Area. The last37 minutes of the eclipse will be visible from around here. Created using Stellarium.

Eclipse map for the June 10, 2021 Annular Eclipse

Eclipse map for the June 10, 2021 Annular Eclipse. Click on the image to see the original PDF. Credit NASA/GSFC Fred Espenak.

01/09/2020 – Ephemeris – What is Ephemeris about?

January 9, 2020 2 comments

Ephemeris for Thursday, January 9th. Today the Sun will be up for 9 hours and 1 minute, setting at 5:20, and it will rise tomorrow at 8:18. The Moon, 1 day before full, will set at 8:15 tomorrow morning.

The Ephemeris program has been a labor of love of mine for going on 45 orbits of the Sun this June. The topics are astronomy and space. What can be seen with the naked eye, binoculars or a small telescope. We look at constellations visible in the evening, their stories, both of western civilization and of the native peoples of our land. We look at the planets, especially the naked-eye planets on Wednesday, and whenever the Moon appears close to one to point it out. We also give heads up on upcoming events like eclipses and meteor showers, plus local events like viewing opportunities we call star parties. I have a companion blog, often illustrated: It’s at bobmoler dot wordpress dot com.

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

Addendum

When the Moon is in the evening sky I will talk about what can be seen on its surface that night, usually near the terminator, which in the evening is the sunrise line, where the shadows are longest. I don’t cover the Moon every month.  Search “Moon” to find all the posts that I do.  I just might have a post on the phase you are interested in. Otherwise when the bright Moon overpowers the constellations, I talk about what we know about the bright stars visible, astronomical news or concepts, whatever can be explained in 45 seconds. Sometimes I can only whet your appetite.  Click the about button above for more information about the Ephemeris program and me.

01/08/2020 – Ephemeris – Looking for the naked-eye planets

January 8, 2020 Comments off

Ephemeris for Wednesday, January 8th. Today the Sun will be up for 9 hours even, setting at 5:19, and it will rise tomorrow at 8:19. The Moon, 2 days before full, will set at 7:15 tomorrow morning.

Let’s look at the naked-eye planets for this week. Venus is our evening star low in the southwest in the early evening. It will set at 8:20 p.m. Saturn sets only 20 minutes after sunset and is not visible. It will pass behind the Sun on the 13th and will then join Jupiter in the morning sky. Jupiter is too close to the Sun in the morning twilight to be seen. Mars is visible in the morning sky and will rise in the east-southeast at 5:02 a.m. It’s not very bright because it’s 198 million (319 million km) miles away, but it’s getting slowly closer to the Earth at the rate of about 4 million miles (6 million km) a week. Mercury is now too close to the Sun to be seen in the morning, but will move into the evening sky on Friday.

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

Addendum

Venus and the Gibbous Moon in the evening

Venus and the Gibbous Moon in the evening tonight at 7 p.m. January 8, 2020. Orion is still easily spotted in the moonlight. Click on the image to enlarge. Created using Stellarium.

Binocular Moon this evening

The gibbous Moon as it might appear in binoculars at 7 p.m. January 8, 2019. Created using Stellarium.

Very enlarged Venus

Venus, much larger than it would appear in any telescope to show its gibbous phase, tonight January 8, 2019. Created using Stellarium.

Mars in the morning

Mars in the morning with the bright stars at 7 a.m. January 9, 2020. Note that Mars is approaching the red giant star Antares. The name Antares means “Rival of Mars” (Ant – anti, Ares -the Greek god of war that the Romans appropriated as Mars). Mars will pass 4.8 degrees north of Antares on the 17th. Created using Stellarium.

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on January 8, 2020. The night ends on the left with sunrise on the 9th. Click on the image to enlarge. Created using my LookingUp program.

 

 

01/07/2020 – Ephemeris – What the heck is an ephemeris? Plus my Betelgeuse update

January 7, 2020 Comments off

Ephemeris for Tuesday, January 7th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:18, and it will rise tomorrow at 8:19. The Moon, 3 days before full, will set at 6:09 tomorrow morning.

What the heck is an ephemeris? According to Wikipedia: “In astronomy and celestial navigation, an ephemeris (plural: ephemerides; from Latin ephemeris, meaning ‘diary’, from the Greek,… meaning ‘diary, <or> journal’) gives the positions of… astronomical objects… at a given time or times. Historically, positions were given as printed tables of values, given at regular intervals of date and time.” My tables are now databases which I generate for the year during the prior December from published algorithms. I will show all on my blog today: It’s at bobmoler<dot>wordpress<dot>com. (You are already here) I used to have to interpolate values from printed ephemerides for the first 5 or so years.

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

Addenda

An Ephemeris Example

Ephemeris for 2I/Borisov

Here’s an ephemeris for the Interstellar comet for 2I/Borisov AKA C/2019 Q4 (Borisov) from the Jet Propulsion Laboratory’s (JPL) Horizons system.

R.A. is right ascension – East-west position in the sky, like longitude on the Earth, only it’s in hours, minutes and seconds.  One hour = 15 degrees.

DEC is declination – North-south position, in the sky, exactly like latitude on the Earth in degrees, minutes and seconds.

J2000.0 means that the above coordinates are based on where the vernal equinox point in the sky was on January 1, 12:00 Terrestrial Time, 2000.  Or January 1, 2000, 11:58:55.816 UTC as reported in Wikipedia.

APmag – Apparent visual magnitude.  Magnitudes are like golf scores.  The higher magnitude the dimmer the object.  It’s really, really dim.

delta – Distance from the Earth in terms of Astronomical Units (AU).  1 AU is Earth’s mean distance from the Sun.

deldot – The change in delta.  It’s in kilometers per second.  If positive, it’s going away.

For more information on how I produce ephemerides for this program go here: https://bobmoler.wordpress.com/2019/01/22/

The dimming of Betelgeuse

I finally got a clear evening.  However snow and freezing rain the rest of the week.

Orion at 7:07 p.m. January 6, 2020

Betelgeuse in Orion at 7:07 p.m. January 6, 2020. Taken with my Samsung Galaxy S10+ in the moonlight. Compare the brightness of Betelgeuse with Rigel, Bellatrix and the belt stars.

Orion's brightest stars

Orion’s brightest stars with their names for 9 p.m. January 7, 2019. Click on the image to make Orion a giant hunter. Created using Stellarium.

See last Thursday’s post on the dimming of Betelgeuse: https://bobmoler.wordpress.com/2020/01/02/

01/06/2020 – Ephemeris – The Earth was closest to the Sun in its orbit yesterday

January 6, 2020 Comments off

Ephemeris for Monday, January 6th. Today the Sun will be up for 8 hours and 57 minutes, setting at 5:17, and it will rise tomorrow at 8:19. The Moon, half way from first quarter to full, will set at 5:02 tomorrow morning.

Yesterday’s perihelion, or closest point of the Earth to the Sun of roughly 91.4 million miles (147 million km) is only 1.7% closer to the Sun than average. It doesn’t do much to make our winters warmer, but it does make winter the shortest season. That’s because the Earth travels faster when near the Sun than when it’s farther away. Winter lasts only 89 ½ days. The Earth’s aphelion, when it’s farthest from the Sun will be on the 4th of July, in summer, making that the longest season at 93 ½ days. Of course being this far north it feels like winter is longer than summer, but astronomically it’s the other way around. Being a leap year, with February having 29 days, spring will arrive a calendar day early on the 19th of March.

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

Addendum

Earth's orbit

The Earth’s orbit, somewhat exaggerated, showing perihelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.

Seasons for 2020

The Seasons for 2020 from data in Astronomical Tables of the Sun, Moon, and Planets Third Edition by Jean Meeus. Date and times are in TD, Dynamical Time. Subtract about 1 minutes to convert to Universal Time (UT).  Also subtract 5 hours for Eastern Standard Time and 4 hours for Eastern Daylight Time.

For and explanation of the Cross-Quarter Days column, check out my Ground Hog Day post last year:  https://bobmoler.wordpress.com/2019/02/02/02-02-2019-ephemeris-extra-groundhog-day-and-other-seasonal-days/

 

01/03/2020 – Ephemeris – Astronomical events this weekend

January 3, 2020 Comments off

Ephemeris for Friday, January 3rd. The Sun will rise at 8:20. It’ll be up for 8 hours and 54 minutes, setting at 5:14. The Moon, 1 day past first quarter, will set at 1:49 tomorrow morning.

Tonight at 8 p.m. there will be a telescope clinic by the Grand Traverse Astronomical Society at the Rogers Observatory south of Traverse City on Birmley Road for those who have either received a telescope for Christmas or have one hidden away in an attic, to learn how to use it. Bring ‘em if you’ve got ‘em.

Tomorrow morning we’ll see the peak of the Quadrantid meteor shower after the Moon sets. The radiant for this shower is near the handle of the Big Dipper, though they will be seen all over the sky. The peak should be around 3:20 a.m. with the possibility of over a hundred meteors visible per hour.

On Sunday at 5 a.m. the Earth will be its closest to the Sun for the year of 91,394,000 miles (147,085,000 km).

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

Addendum

Quadrantid radiant

The location of the Quadrantid radiant at 3:20 a.m. January 4, 2020 for the peak of the meteor shower. Created using Stellarium.

Earth's orbit

The Earth’s orbit, somewhat exaggerated, showing perihelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.