Archive

Archive for the ‘The Moon’ Category

01/30/2023 – Ephemeris – Two planetary events are happening today

January 30, 2023 Leave a comment

This is Ephemeris for Monday, January 30th. Today the Sun will be up for 9 hours and 44 minutes, setting at 5:48, and it will rise tomorrow at 8:03. The Moon, 2 days past first quarter, will set at 4:34 tomorrow morning.

Today, the planet Mercury was seen as far away from the Sun as it can get for this time of year in the morning sky. It’s called “greatest western elongation”, and it’s distance from the sun and angle is 25 degrees. It’s going to stay pretty close to that for about the next week or so, it’ll be visible if it ever clears up. This is about the latest time one can see Mercury morning elongations this for this time of year. We’re running out of the correct angles for it. This evening, if it’s clear, the planet of Mars will appear near the waxing gibbous Moon. Early on in the evening Mars will be to the upper left of the Moon, which will be approaching it by about its own diameter every hour, until about 1 o’clock in the morning when Mars will it’s closest above the Moon it should be a striking sight.

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.

Addendum

Mercury, brighter than it would appear with orbit, created by Stellarium. Mercury is going up, left and down in a counterclockwise motion.
The Moon and Mars as created in Stellarium for 12:50 am tonight, January 31, 2023. Mars will actually appear less bright compared to the Moon than it appears here.

12/08/2022 – Ephemeris – Tonight’s full-ish Moon is near where the June solstice Sun was

December 8, 2022 Comments off

This is Ephemeris for Thursday, December 8th. Today the Sun will be up for 8 hours and 54 minutes, setting at 5:02, and it will rise tomorrow at 8:08. The Moon, 1 day past full, will rise at 5:10 this evening.

The bright Moon near full in December rises very high in the south around midnight to 1 am. It is near where the Sun is at the summer solstice. Actually, tonight it is to the lower right of the constellation of Gemini, and to give a topical reference. Tonight, the Moon appears as a soccer ball being kicked by Castor, one of the twins. It’s right off the toe of his foot. In June, the Sun and Full Moon’s positions are reversed. The Sun rises very high in the southern sky at local noon, while the full moon stays low in the south. Or Moon is odd in that respect, Most large satellites of the other planets orbit over their primary’s equator. Our Moon’s orbit is aligned to about 5 degrees off Earth’s own orbit of the Sun, which is angled at 23 and a half degrees from Earth’s equator.

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.

Addendum

The Moon near the summer solstice point

The Moon near the summer solstice point overnight tonight at 1:15 am (the 9th). The sky is overlaid with the equatorial grid. The bright blue line that runs just above Orion’s belt is the celestial equator. The declination lines match Earth’s latitude lines are 10 degrees apart. The vertical blue lines are right ascension lines, like earthly longitude lines, and are 15 degrees apart. Each one represents one hour. The orange line is the ecliptic, the path of the Sun in the sky, also the plane of the Earth’s orbit. The red line is the Moon’s orbit, which is inclined by about 5 degrees to the ecliptic. Click on the image to enlarge it. Created using Stellarium and LibreOffice Draw.

12/06/2022 – Ephemeris – The Moon will pass in front of Mars tomorrow night

December 6, 2022 Comments off

This is Bob Moler with Ephemeris for Tuesday, December 6th. Today the Sun will be up for 8 hours and 57 minutes, setting at 5:02, and it will rise tomorrow at 8:06. The Moon, 1 day before full, will set at 7:45 tomorrow morning.

Late tomorrow evening we might get to view a really cool event, clouds permitting, when the full moon will cover or in astronomical lingo occult the planet Mars. In the Grand Traverse Region, this will occur for an hour between approximately 10:15 to 11:15 pm. The exact times depend on your location, and can vary by a minute or two over the IPR coverage area. Being a full moon, Mars might be difficult to spot. It may take binoculars to spot it below, left of the Moon by 9:30, and a small telescope when Mars is near the edge of the Moon. The disappearance of Mars will be at the Moon’s 7 o’clock position, and reappearance at the 4 o’clock position.

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.

Addendum

Mars ingress and egress chart and times for Traverse City, MI

Mars ingress and egress chart and times for Traverse City, MI. The times will vary by a minute or two in the IPR listening area, ingress being earlier to the west and north and later east and south. Egress times will be earlier west and later east of Traverse City. Mars takes about a minute to completely disappear and reappear again because it’s not an unresolvable point like stars.

Occultation of Mars map

Occultation of Mars map. The occultation of Mars by the Moon will be visible from within the bounded area. For Traverse City, MI, Mars will disappear around 10:15 pm, December 7, 2022, and reappear around 11:15 pm.

In astronomical events of solar eclipses and occultations YOU are part of the event. No, not you, but your location. Whether you see the event or not or what time the contacts (ingress, egress) happen depends on your location. And will happen for that location whether you are there, or it’s clear, or not.

12/05/2022 – Ephemeris – Mars will hide behind the full Moon Wednesday night

December 5, 2022 Comments off

This is Ephemeris for Monday, December 5th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:02, and it will rise tomorrow at 8:05. The Moon, 2 days before full, will set at 6:36 tomorrow morning.

Late Wednesday night we might get to view a really cool event when the full moon will cover or in astronomical lingo occult the planet Mars. In the Grand Traverse Region, this will occur for an hour between approximately 10:15 to 11:15 pm. The exact times depend on your location, and can vary by several minutes or more. Being a full moon, Mars might be difficult to spot. I’ll have more and hopefully more accurate information tomorrow. When astronomical objects line up like this, it’s called a syzygy. This time it’s a lineup of the Sun, Earth Moon and Mars in nearly a straight line, with both the Moon and Mars in opposition from the Sun on the same night. When the Moon is in opposition, we call it a full moon instead.

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.

Addendum

Mars ingress and egress chart and times for Traverse City, MI

Mars ingress and egress chart and times for Traverse City, MI. The times will vary by a minute or two in the IPR listening area, ingress being earlier to the west and north and later east and south. Egress times will be earlier west and later east of Traverse City.

Occultation map Mars 2022-12-8 UT

World map showing the area that the occultation of Mars will be visible. Occultation visibility will move from west to east. Credit: Occult version 4.

 

11/29/2022 – Ephemeris – Observing the Moon tonight

November 29, 2022 Comments off

This is Ephemeris for Tuesday, November 29th. Today the Sun will be up for 9 hours and 6 minutes, setting at 5:04, and it will rise tomorrow at 7:58. The Moon, 1 day before first quarter, will set at 11:28 this evening.

The illuminated part of tonight’s Moon will be a fat crescent shape, 12 hours, give or take from first quarter. Besides the lunar seas visible there are some large craters on its terminator, or sunrise line On the upper right are two distinctive craters near each other. The larger is Aristoteles named after the Greek philosopher Aristotle which is 53 miles wide. The smaller is Eudoxus, named after an older Greek philosopher, 41 miles in diameter. Both of these should be visible in small telescopes or even binoculars. They stand out because there are only a few small craters around them in pretty much flat terrain. Meanwhile Artemis 1’s Orion capsule is continuing to make a large lazy loop around the Moon before heading back to the Earth in 12 days.

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.

Addendum

Annotated Moon animation

Annotated Moon animation as it might appear tonight at 8 pm, November 29, 2022. Created using Stellarium and GIMP.

Earthset from Artemis I's Orion spacecraft

Earthset from Artemis I’s Orion spacecraft, as it moves around to the far side of the Moon. Click on the image to enlarge it. Credit: NASA

11/28/2022 – Ephemeris – The Artemis Program

November 28, 2022 Comments off

This is Ephemeris for Monday, November 28th. Today the Sun will be up for 9 hours and 8 minutes, setting at 5:04, and it will rise tomorrow at 7:57. The Moon, 2 days before first quarter, will set at 10:09 this evening.

Now that the Artemis I mission is ongoing, and the spacecraft is in a large orbit of the Moon, it’s time to look at the rest of the program. In 2024 the SLS or Space Launch System, which is the name for the whole rocket, will send a four-person crew in their Orion Capsule around the Moon and back. From what I’m seeing right now, it will be a simple mission. It doesn’t appear that they will actually orbit the Moon other than a free return trajectory back to the Earth. The mission a year or so after that will be one to attempt to land on one of the few flat sites near the south pole of the Moon. Speaking of the Moon, the planet Saturn will be about eight of the Moon’s diameter’s north or above the Moon tonight.

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.

Addendum

Earthset from Artemis I's Orion spacecraft

Earthset from Artemis I’s Orion spacecraft, as it moves around to the far side of the Moon. Click on the image to enlarge it. Credit: NASA

10/27/2022 – Ephemeris – Trying to spot the young Moon tonight

October 27, 2022 Comments off

This is Bob Moler with Ephemeris for Thursday, October 27th. Today the Sun will be up for 10 hours and 24 minutes, setting at 6:38, and it will rise tomorrow at 8:15. The Moon, 2 days past new, will set at 7:55 this evening.

The Moon is again making its appearance in the evening sky as a thin crescent. The crescent appearance is because the moon is mostly between the Earth and the Sun. So we are seeing mostly its night side, with just a sliver of it being sunlit. But the Moon has the Earth in its sky, which is quite big and bright, much brighter than the Moon in our skies. And when the Moon’s phase is thin, the Earth, having the opposite phase, will be a nearly full gibbous orb. The Earth illuminates the Moon’s night side with earthlight. We call it earthshine, when the whole Moon appears faintly inside the crescent. It’s also known more poetically as the “Old moon in the new moon’s arms.” If you’re not sure, because the effect is faint, check it out in binoculars. The effect should last another night.

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

Earthshine by Bob Moler

An old picture of mine overexposing the crescent Moon to bring out earthshine. The moon was a wider crescent than it will appear to be tonight.

10/06/2022 – Ephemeris – Artemis I rescheduled

October 6, 2022 Comments off

This is Ephemeris for Thursday, October 6th. Today the Sun will be up for 11 hours and 27 minutes, setting at 7:14, and it will rise tomorrow at 7:48. The Moon, 3 days before full, will set at 4:52 tomorrow morning.

Artemis 1 was going to launch on September 27th, But Hurricane Ian had other plans, so the rocket was trundled back to the Vertical Assembly Building. There, a battery or components of the auto destruct mechanism had to be swapped out before they attempted to launch again. All rockets launched from the US are required to be equipped with a destruct package to blow up the rocket if it veers off course, to not endanger lives on the ground. There are other tweaks, including charging or replacing batteries in all the CubeSats that are on board. The next possible launch period runs from November 12th to the 27th, with four blackout dates within that period. The weather should be better, being the tail end of hurricane season.

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

Artemis I November launch calendar

Artemis I November launch calendar. Dates in green are possible launch dates. I’m not sure, but red dates are also forbidden because the Orion Capsule will experience more than 90 minutes in shadow at a time. It’s powered by solar panels. Light green dates allow a long mission of 1 1/2 orbits of the Moon in the distant retrograde orbit (DRO). The dark green dates can only have 1/2 a DRO. Source: NASA.

10/03/2022 – Ephemeris – There’s something on the Moon that’s straight and not circular

October 3, 2022 Comments off

This is Ephemeris for Monday, October 3rd. Today the Sun will be up for 11 hours and 36 minutes, setting at 7:19, and it will rise tomorrow at 7:44. The Moon, 1 day past first quarter, will set at 12:55 tomorrow morning.

On this program, I try to talk about celestial objects one can see or find with the naked eye. Once found, I do talk about what they would look like in binoculars or small telescope. For those wanting more information, consult my blog bobmoler.wordpress.com where my scripts are posted with more information, illustrations and charts. The thing I’m talking about today is a feature on the Moon that’s visible only two nights a month. The day after first quarter, and the day after last quarter. It’s the straightest thing on the Moon, called the Straight Wall, that’s 67 miles (110 km) long and 900 feet (300 m) high. It is close to the terminator, the Moon’s sunrise line, about halfway from the center of the Moon to the south edge. It’s the thinnest dark line you can imagine.

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

The Straight Wall or, officially in Latin, Rupes Recta, is a rectilinear fault. It isn’t really a wall, but a 7 degree slope. Once the Sun rises past seven degrees in that location of the Moon, it disappears. Near local sunset, a day after last quarter, the low sun in its sky shines more on it than the flat ground, so it shows up bright. Click on the image to enlarge it. The information and images were created from Virtual Moon Atlas, which is free software for MS Windows. I have a link to it on this page.

09/30/2022 – Ephemeris – View the Sun and Moon tomorrow in the Grand Traverse Area!

September 30, 2022 Comments off

This is Ephemeris for Friday, September 30th. Today the Sun will be up for 11 hours and 45 minutes, setting at 7:25, and it will rise tomorrow at 7:40. The Moon, 2 days before first quarter, will set at 9:57 this evening.

There are two observing sessions tomorrow in the Traverse City area with the assistance of the Grand Traverse Astronomical Society. First at the Dennos Museum Center grounds, from 2 to 4 pm, there will be telescopes to safely view the Sun. The Sun’s eleven-year sunspot cycle is getting active again. There will be telescopes to see those sunspots, and special solar hydrogen alpha telescopes to view the Sun’s chromosphere and any prominences above the Sun that day. From 8 to 10 pm, Northwestern Michigan College’s Rogers Observatory will be open for International Observe The Moon Night. There will also be a telescope on the 200 Block of East Front Street to observe the Moon during this time. Of course, all this is contingent on clear or mostly clear skies.

Update: It’s supposed to be nice this weekend, after a week of cold and rain.

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

Later today I’ll add a Moon Map for tomorrow evening and what the Sun looks like today, which should give a clue to what’s happening on the Sun now.

Sun in white light (How we normally see it with a solar filter)

Sun in white light

The Sun in white light, by the Solar Dynamics Observatory on September 30, 2022. What is seen is the photosphere, the visible “surface” of the Sun, where the energy transport from the interior changes from convection to radiation. The apparent roughness of the surface are the tops of the convection cells, called granules, which are usually about 600 miles wide that bubble up and recede. The numbers label active areas. The dark spots are sunspots, areas of intense magnetic activity. Brighter wispy or splotchy areas are faculae and are associated with sunspots or precursors of a new group forming.  The rotation of the Sun will move the surface features from left to right in this image with north up. Telescopes may show the image upside down or mirror reversed. Click on the image to enlarge it. Credit NASA/SDO.

Sun in the light of the Hydrogen Alpha wavelength. Light absorbed and emitted by the hydrogen atom.

The Sun in Hydrogen-Alpha light

The Sun in Hydrogen-Alpha light, taken at 10:19 EDT today, September 30, 2022. It is in the same orientation as the SDO image above, but may have been taken at a different time of the day. This image was taken from the web page https://gong2.nso.edu/products/tableView/table.php?configFile=configs/hAlpha.cfg I colorized the image to show how it would look in a Hydrogen-Alpha telescope, of which we may have several, both the society’s and personal. The images may be dim since they select one narrow frequency of light from the broad spectrum of white light coming up from the photosphere. Its temperature is 10,000 degrees F. The thin dark markings are called filaments. These are the same thing as the bright prominences seen off the edge or limb of the Sun. Brighter areas of the chromosphere are called plages and are associated with active regions. The Chromosphere is a thin layer of the Sun’s atmosphere lying above the photosphere only 3,000 miles thick, and slightly hotter than the photosphere, its appearance is rougher than the granules of the photosphere. It reminds me of uneven, red grass that hasn’t been mown in a few weeks. They grow and recede in minutes. Sometimes a bright spot will appear in a sunspot group. These are solar flares and are caused by magnetic disruptions in sunspot groups. They last only a relatively few minutes but emit x-rays, electrons and protons as the most energetic explosions in the solar system. The x-rays arrive at Earth in 8 and a half minutes at the speed of light, the particles a day or two later will affect the Earth’s magnetic field if aimed in our direction, causing the aurora (northern and southern lights), and possibly disrupt communications and the power grid. On Earth, it’s called a geomagnetic storm.

The Moon for Saturday evening during the International Observe the Moon Night

The Moon as it should appear at 9 pm EDT, October 1st, 2022

The Moon as it should appear at 9 pm EDT, October 1st, 2022. The telescopic image would be sharper than this. Created using Virtual Moon Atlas.

Download page of maps from the Official 2022 International Observe the Moon Night website.

Images in astronomical telescopes produce images of various orientations. They may be right side up or upside down, mirror reversed or both. Telescopes with an odd number of mirrors produce mirror images. Astronomers are used to it, though they have a preferred orientation… The one their favorable telescope produces.

Come on out!