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Posts Tagged ‘Mars opposition’

10/28/2022 – Ephemeris – Mars is turning around this weekend

October 28, 2022 Comments off

This is Bob Moler with Ephemeris for Friday, October 28th. Today the Sun will be up for 10 hours and 21 minutes, setting at 6:37, and it will rise tomorrow at 8:16. The Moon, 3 days past new, will set at 8:39 this evening.

This Sunday the 30th, the planet Mars will cease its normal eastward motion in relation to the stars, and backtrack to the west for a while. The instant Mars stops its eastward motion, it is said to be stationary. The backtracking is called retrograde motion, which was hard for ancient astronomers to explain because they thought the Earth was not moving and in the center of the universe. And the planets moved in uniform circular motion. So said the Greeks, because they thought that things in the heavens were perfect, not like the imperfect things of the Earth. Mars was a hard case. Its motion was definitely not uniform or circular. To Copernicus, the retrograde motion meant that the Earth was a planet passing another planet in their race around the Sun.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Mars retrograde path 2022-2023

Mars retrograde path from October 29, 2022 to January 11, 2023 against the stars of Taurus the bull. It will be at opposition on December 7, and actually closest to the Earth on November 30 at 50.61 million miles or 81.45 million kilometers. In the upper right is the beautiful Pleiades star cluster, also known as the Seven Sisters. Below and right is the V shaped star cluster that represents the face of Taurus the bull, with the bright red star Aldebaran as the bull’s angry red eye. That V of stars is called the Hyades, who in mythology were the half sisters to the Pleiades. Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.

07/27/2018 – Ephemeris – Mars is at opposition from the Sun today

July 27, 2018 Comments off

Ephemeris for Friday, July 27th. The Sun rises at 6:23. It’ll be up for 14 hours and 50 minutes, setting at 9:14. The Moon, at full today, will rise at 9:16 this evening.

The planet Mars was at opposition with the Sun early this morning, that is opposite the Sun in the sky. It is a time when a planet rises at sunset and sets at sunrise. For us it will rise tonight at 9:40 p.m. 26 minutes after sunset and will set tomorrow at 6 a.m., 24 minutes before sunrise. This odd behavior is due to the fact that Mars is actually south of a lime from the Sun through the Earth. Mars’ orbit is tilted to the Earths’ so it will appear lower in the sky as one would expect for a planet in its position. Today Mars is 35.9 million miles (57.7 million km) away. In four days it will be a bit closer to us due to its elliptical orbit taking it a bit closer to the Sun. How much closer? About 93,000 miles (150,000 km) to us.

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

Addendum

Retrograde Mars Path 2018

This chart is shown with the horizontal being parallel to the ecliptic, which is the horizontal line near the top of the image.  Created using Cartes du Ciel (Sky Charts).

Retrograde motion explained

Created using Cartes du Ciel (Sky Charts).

Mars at the meridian at opposition

Mars on opposition day, July 27, 2018 at 1:55 a.m. as it crossed the meridian due south. In the Interlochen/Traverse City area a bit south of 45 degrees north latitude. Mars appears a an altitude of slightly less than 20 degrees altitude. Created using Stellarium.

Update

Mars at opposition and the full Moon

Mars at opposition and the full Moon at 2:01 a.m. July 27, 2018. I thought I’d go out near the Mars transit time this morning and photograph the Moon and Mars. Earlier we had a pop-up rain shower, and the clouds were clearing out. Got a lucky shot.

06/28/2018 – Ephemeris – Saturn at opposition, what it means

June 28, 2018 Comments off

Ephemeris for Thursday, June 28th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:32, and it will rise tomorrow at 6:00. The Moon, at full today, will rise at 9:54 this evening.

Just before midnight last night Saturn was in opposition to the Sun. We’re not talking about an argument here. To the astronomer opposition simply means that a planet, in this case Saturn, is 180 degrees from the Sun, or opposite the Sun in the sky. It is a time when the planet rises at sunset and sets at sunrise. It is also a time when the planet is around its closest to the Earth. It’s not a big deal for Saturn, which is almost 10 times farther from the Sun than we are. However it is a big deal for a nearby planet like Mars, which at the end of July will be closer to us than at any time since 2003, at 35.8 million miles. That’s a big deal since Mars is a small planet, a bit more than half the size of the Earth.

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

Addendum

The apparent sizes of Saturn and Mars

The apparent sizes of Saturn and Mars as seen from the Earth at opposition and solar conjunction. All at the same scale. Created using Cartes du Ciel (Sky Charts).

05/06/2016 – Ephemeris – Learn about Monday’s transit of Mercury tonight

May 6, 2016 Comments off

Ephemeris for Friday, May 6th.  The Sun rises at 6:25.  It’ll be up for 14 hours and 29 minutes, setting at 8:54.  The Moon is new today, and won’t be visible.

Learn more about next Monday’s transit of Mercury across the Sun at tonight’s meeting of the Grand Traverse Astronomical Society at 8 p.m. at the Northwestern Michigan College’s Rogers Observatory, on Birmley Road, South of Traverse City.  Afterward at 9 p.m., there will be another program and weather permitting there will be viewing of Jupiter, and later Mars.  On Monday the Society will host transit viewing at two locations.  The transit runs 6 ½ hours from 7:12 a.m. to 2:42 p.m.  The Rogers Observatory will be open for that period.  Also telescopes with be stationed at the Dune Climb at the Sleeping Bear Dunes National Lakeshore by yours truly to view the transit.  The event is not visible to the naked eye and dangerous to even attempt it.

The program will also preview the coming opposition of Mars and closest approach since 2003 on the 30th.

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

Addendum

I posted these yesterday, but here they are again:

Transit Map

Transit visibility map with added captions to make it more readable. Credit United States Naval Observatory, The Astronomical Almanac Online.

rack of the Transit of Mercury

The track of Mercury across the face of the Sun. Mercury will travel from upper left to lower right. Mercury will not be visible until it impinges upon the disk of the Sun. Credit IOTA’s program Occult4.

From IOTA’s Occult4 program

Transit of Mercury on 2016 May 9 (TT)
   {'+' => next day; '-' => previous day }
                                           Overhead at
     Geocentric Event      UTC         P.A.  Long  Lat
                         h  m  s       o      o    o 
[1]  Exterior Ingress   11 12 16     83.1     11   17
[2]  Minimum Separation 14 57 38             -45   18
[3]  Exterior Egress    18 42 23    224.4   -102   18

Minimum sepn 318.5";  Radii - Sun 950.4", Mercury 6.0"
delta T =  68.2 secs,  Ephemeris = DE0

Note:  These timings are geocentric.  Occult4 has timings for various cities of the world.  Occult4.0.2 can be downloaded here.  They can vary by several minutes for different cities due to parallax.

I will post more information on the transit in an Ephemeris Extra tomorrow.

04/29/2016 – Ephemeris – Let’s preview the merry skies of May

April 29, 2016 Comments off

Ephemeris for Arbor Day, Friday, April 29th.  The Sun rises at 6:34.  It’ll be up for 14 hours and 10 minutes, setting at 8:45.   The Moon, at last quarter today, will rise at 3:01 tomorrow morning.

Sunday starts the month when the promise of spring is finally fulfilled.  Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 16 minutes Sunday to 15 hours 20 minutes on the 31st.  The altitude, or angle, of the Sun above the southern horizon at local noon will ascend from 60 degrees Sunday to 67 degrees at month’s end.  The altitude of the sun in the Straits area will be a degree lower than that but your daylight will be a few minutes longer.   The big event of May will be the transit of the tiny planet Mercury across the face of the Sun on May 9th.  I’ll have more on that next week.  Also Mars will be in opposition from the Sun on the 22nd which due to its elliptical orbit will actually be closest to us 8 days later on the 30th at 46.779 million miles (75.284 million km).

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

Addendum

May Star Chart

May 2016 Star Chart

Star Chart for May 2016. Created using my LookingUp program. To enlarge in Firefox Right-click on image then click View Image.

The planets and stars are plotted for the 15th at 11 p.m. EDT.  That is chart time.  Note, Traverse City is located approximately 45 minutes behind our time meridian.  (An hour 45 minutes behind our daylight saving time meridian.) To duplicate the star positions on a planisphere you may have to set it to 1:45 earlier than the current time.

Evening nautical twilight ends at 10:00 p.m. EDT on the 1st, increasing to 10:43 p.m. EDT on the 31st.

Morning nautical twilight starts at 5:20 a.m. EDT on the 1st, and decreasing to 4:38 a.m. EDT on the 31st.

Add a half hour to the chart time every week before the 15th and subtract a half hour for every week after the 15th.  Before the 13th also subtract an hour for Standard Time.

For a list of constellation names to go with the abbreviations click here.

  • Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star
  • A leaky Big Dipper drips on Leo
  • Follow the arc of the handle of the Big Dipper to the star Arcturus
  • Extend the ac to a spike to point to Spica

Calendar of Planetary Events

Credit:  Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)

To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

Times are Eastern Time.  Some additions made to aid clarity.

    Date   Time      Event
May 01 Su            Venus: 9.8° W
    02 Mo  9:27 p.m. Moon Descending Node
    04 We  2:45 p.m. Eta Aquarid Shower: ZHR = 60
    06 Fr 12:14 a.m. Moon Perigee: 357800 km
    06 Fr  3:30 p.m. New Moon
    08 Su  4:21 a.m. Moon-Aldebaran: 0.5° S
    09 Mo  7:12 a.m. Mercury transit begins
    09 Mo 10:57 a.m. Mercury mid-transit
    09 Mo  2:42 p.m. Mercury transit ends
    09 Mo  5:54 p.m. Moon North Dec.: 18.4° N
    13 Fr  1:02 p.m. First Quarter
    14 Sa  3:06 a.m. Moon-Regulus: 2.5° N
    15 Su  5:30 a.m. Moon-Jupiter: 2.2° N
    15 Su  4:39 p.m. Moon Ascending Node
    18 We  6:06 p.m. Moon Apogee: 405900 km
    21 Sa  5:15 p.m. Full Moon
    22 Su  7:15 a.m. Mars Opposition
    22 Su  5:59 a.m. Moon-Saturn: 3.5° S
    24 Tu  7:16 a.m. Moon South Dec.: 18.5° S
    29 Su  8:12 a.m. Last Quarter
    30 Mo 12:45 a.m. Moon Descending Node
    30 Mo  5:36 p.m. Mars closest to the Earth 0.50321 AU
Jun 01 We            Venus: 1.5° W

Transit of Mercury

May 9, 2016 7:12 a.m. (11:21 UT) to 2:42 p.m. (18:42 UT)

rack of the Transit of Mercury

The track of Mercury across the face of the Sun. Mercury will travel from upper left to lower right. Mercury will not be visible until it impinges upon the disk of the Sun. Credit IOTA’s program Occult4.

Transit Map

The map showing where the transit is visible in whole or in part. If using Firefox enlarge the map by right clicking on it and select View Image.

 

04/08/2014 – Ephemeris – Mars is at opposition today!

April 8, 2014 Comments off

Ephemeris for Tuesday, April 8th.  The sun will rise at 7:10.  It’ll be up for 13 hours and 7 minutes, setting at 8:18.   The Moon, 1 day past first quarter, will set at 4:10 tomorrow morning.

Mars is at opposition from the Sun today.  That doesn’t mean that Mars and the Sun are opposed to each other. Well, I guess they are, sort of.  It really means that the Sun and Mars are opposite one another in the sky with Mars rising at sunset, staying up all night and setting at sunrise.  That puts the earth smack dab between the Sun and Mars.  For most planets this is the time of closest approach.  Mars, however, has a markedly elliptical orbit, and in its orbit, it is moving closer to the sun, so it will actually come a bit closer to the Earth this go around on April 14th, next Monday when it will be 372,000 miles closer.  That’s not much out of 57 million miles.  Still Mars is a tiny planet in telescopes.

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

Addendum

Mars' closest approaches with the earth 2003 to 2018.  Created with my LookingUp program.

Mars’ closest approaches with the earth 2003 to 2018. Created with my LookingUp program.

Mars tonight

Mars through a telescope tonight (April 8, 2014). Apparent diameter 15.1″. Created using Stellarium.

Mars in 2003

Mars at its closest approach in 50,000 or so years on August 27, 2003. Apparent diameter 25.1″. Created using Stellarium.

Apparent diameters are in seconds or arc.  One second of arc is 1/3600th of a degree. or about 1/1800th of the width of the Moon or Sun.

03/28/2014 – Ephemeris – Mars approaches

March 28, 2014 Comments off

Ephemeris for Friday, March 28th. The sun will rise at 7:30. It’ll be up for 12 hours and 34 minutes, setting at 8:04. The moon, 2 days before new, will rise at 6:40 tomorrow morning.

The planet Mars is making its every 26 month on average close approach to the Earth. Mars will reach opposition from the sun on April 8th, rising at sunset and setting at sunrise. Due to Mars’ strongly elliptical orbit, it will actually be closest to us 6 days later on April 14th. That distance will be about 57.4 million miles, nearly twice that if its closest distance of 34.6 million miles it came back in 2003. But take heart, the opposition distances are closing. On July 31, 2018 it will again be below 36 million miles away. Even at its closest, Mars is a tiny object for the telescope. It’s half the size of the Earth and at its closest will appear less that half the size that Jupiter appears to us.

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

Addendum

Mars' closest approaches with the earth 2003 to 2018.  Created with my LookingUp program.

Mars’ closest approaches with the earth 2003 to 2018. Created with my LookingUp program.