Archive
11/19/2018 – Ephemeris – The Leonids’ comet 55P/Tempel-Tuttle
Ephemeris for Monday, November 19th. The Sun will rise at 7:45. It’ll be up for 9 hours and 25 minutes, setting at 5:10. The Moon, half way from first quarter to full, will set at 4:29 tomorrow morning.
We have another day in this year’s extended Leonid meteor peak. In past years, usually every 33 years the Leonid meteors have a super peak, called a meteor storm, where thousands of meteors streak through the skies. These appear for a brief period over a rather small geographic area. In 1966 it occurred principally over the Rocky Mountains. The comet responsible is Comet Tempel Tuttle, independently discovered by two astronomers Tempel and Tuttle in 1865 & 1866. The comet had a 33 year orbit of the Sun, and its orbit crosses very close to the Earth’s orbit. Comets are notorious litter bugs, shedding gas, dust and pebble sized debris as they come close to the warming rays of the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/16/2018 – Ephemeris – The Leonid meteor shower will have several peaks in the next few days
Ephemeris for Friday, November 16th. The Sun will rise at 7:41. It’ll be up for 9 hours and 32 minutes, setting at 5:13. The Moon, 1 day past first quarter, will set at 1:19 tomorrow morning.
We are coming into an extended period where the Leonid meteor shower will be at its peak, or rather there is a chance of up to maybe four peaks as the Earth passes through the debris left by Comet Tempel-Tuttle on past trips through the inner solar system. We are having a pretty bright Moon now, but the best displays of the meteors are going to be occurring in the early morning hours after the Moon sets. The meteors will appear to come from the top of a backward question mark that is the head of the constellation Leo the lion. They will be seen all over the sky, but can be traced back to that point, if it’s a Leonid meteor. The Leonids are most numerous about every 33 years, which is about 15 years from now. Otherwise we get about 15 meteors an hour at peak.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/15/2018 – Ephemeris – Last year’s interstellar visitor was acting funny
Ephemeris for Thursday, November 15th. The Sun will rise at 7:39. It’ll be up for 9 hours and 34 minutes, setting at 5:14. The Moon, at first quarter today, will set at 12:18 tomorrow morning.
Last year about this time a fast moving asteroid with an odd cigar shape passed through the inner solar system. It’s velocity was such that it didn’t come from around here, meaning our solar system. It was named ‘Oumuamua by its discoverers in Hawai’i. It was spotted as it was heading out, away from the Sun. As it does so, it decelerates as the Sun’s gravitational pull tries to pull it back in. After studying its motion, astronomers noticed that it wasn’t decelerating as fast as it should if it was on a simple ballistic trajectory. Something about it was accelerating it, or causing it to not decelerate as fast as it should. Despite rampant speculation that it’s an interstellar craft on social media ‘Omuamua’s acceleration is well within that possible for comets.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/14/2018 – Ephemeris – The bright planets this week
Ephemeris for Wednesday, November 14th. The Sun will rise at 7:38. It’ll be up for 9 hours and 37 minutes, setting at 5:15. The Moon, 1 day before first quarter, will set at 11:18 this evening.
Let’s look at the bright planets for tonight. Two of them are visible in the evening sky. Jupiter will set too soon after sunset to be seen. It will set only 29 minutes after the Sun. Saturn, the ringed planet, will start the evening low in the southwestern sky and will set at 7:59 p.m. Mars will be low in the south as the skies darken tonight. Mars will be due south at 7:15 p.m., and it will set at 12:24 a.m. Mars is moving eastward, crossing the constellation of Aquarius this month. It’s currently at the western edge of Aquarius, moving eastward and northward, so its setting time won’t change much over this month. Venus, our brilliant morning star, will rise at 5:15 a.m. in the east southeast. The blue-white star Spica is just above and right of it now.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
Comet Notes
Two comets will be flirting with naked eye visibility later this month and next month. Newly discovered C/2018 V1 Machholz-Fujikawa-Iwamoto. It will be a morning object in mid-December and be its brightest at the end of this month or early December when it will be cruising through Ophiuchus.
Periodic comet 46P/Wirtanen is moving up from the south and is an evening object. It will pass close to the Pleiades in mid-December and will appear near the bright star Capella around Christmas time.
11/13/2018 – Ephemeris – The Summer Triangle in autumn
Ephemeris for Tuesday, November 13th. The Sun will rise at 7:37. It’ll be up for 9 hours and 39 minutes, setting at 5:16. The Moon, 2 days before first quarter, will set at 10:20 this evening.
The Summer Triangle is still in the sky at 9 p.m., even though it’s November. These three bright stars that straddle the Milky Way are high in the east for most of the summer, move overhead and begin to slide to the west in autumn. We will lose Altair, the southernmost of the three stars at 9 p.m. on the winter solstice, December 21st. We’ll lose the brightest, Vega in January. For the northern half of the IPR listening area the northernmost of the triangle stars, Deneb won’t quite set below a north Lake Michigan horizon. Next spring we’ll be waiting and watching for these three stars to rise, reclaim the skies, and bring again the warm summer skies. The winter skies do however have more bright stars than the summer sky.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/12/2018 – Ephemeris – Orion is rising
Ephemeris for Veterans Day Observed, Monday, November 12th. The Sun will rise at 7:35. It’ll be up for 9 hours and 41 minutes, setting at 5:17. The Moon, 3 days before first quarter, will set at 9:25 this evening.
Just after the Moon sets tonight winter’s most dazzling constellation will be rising, Orion the hunter of Greek myth. The stars of his torso are in a rectangle leaning to the left. Orion’s belt of three stars in a straight line in the center of the rectangle is nearly vertical. The Anishinaabe peoples whose region we live in see the constellation of the Wintermaker rather than Orion. It uses Orion’s torso and belt stars, but his arms are spread wide from Aldebaran in the face of Taurus the bull to the west to Procyon in Canis Minor, which won’t rise until 11 p.m. to the east. The Wintermaker’s arms are wide enough to embrace the entire winter sky. Its name in Anishinaabemowin, which is Biboonikeonini, means “North Wind”.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
11/09/2018 – Ephemeris – The Great Andromeda Galaxy
Ephemeris for Friday, November 9th. The Sun will rise at 7:31. It’ll be up for 9 hours and 49 minutes, setting at 5:21. The Moon, 2 days past new, will set at 7:03 this evening.
In the south at 9, this evening can be found a large square of stars, the Great Square of Pegasus the flying horse, flying upside down to the right. What looks like its hind legs stretching to the left from the upper left corner star is another constellation, Andromeda the chained princess. She is seen in the sky as two diverging curved strings of stars that curve upward. She was rescued by the hero Perseus, a nearby constellation, riding Pegasus. Andromeda’s claim to astronomical fame is the large galaxy seen with the unaided eye just above the upper line of stars. The Great Andromeda Galaxy is 2.5 million light years away. To the naked eye the galaxy appears as a small smudge of light. In binoculars the galaxy is a delicate spindle of light.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/08/2018 – Ephemeris – More constellations of autumn: Andromeda, Triangulum and Aries
Ephemeris for Thursday, November 8th. The Sun will rise at 7:30. It’ll be up for 9 hours and 51 minutes, setting at 5:22. The Moon, 1 day past new, will set at 6:26 this evening.
High in the south at 9 p.m. can be seen the Great Square of Pegasus. From the top left star of the square diverge two curved lines of stars that is Andromeda the chained princess. Just below and left of Andromeda is a slender triangle of stars, none particularly bright. It has a name you can easily see in the stars, Triangulum, the triangle. Early Christians saw it as the Mitre of Saint Peter or the Trinity. Another small constellation seen below Triangulum is the much better known constellation Aries the ram, a small hockey stick of a constellation, not that hard to spot. It is the first constellation of the Zodiac, where the Sun is supposed to enter on the first day of spring. Due to the wobble of the Earth’s axis over the millenia, that honor is now given to Pisces.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/07/2018 – Ephemeris – Two Two evening planets and a morning planet visible now
Ephemeris for Wednesday, November 7th. The Sun will rise at 7:28. It’ll be up for 9 hours and 54 minutes, setting at 5:23. The Moon is new today, and won’t be visible.
Let’s look at the bright planets for tonight. Two of them are visible in the evening sky. Jupiter will set too soon after sunset to be seen. It will set only 44 minutes after the Sun. Saturn, the ringed planet, will start the evening low in the southwestern sky and will set at 8:24 p.m. Mars will be low in the south as the skies darken tonight. and is now 77.8 million miles (125.2 million km) away. Mars will be due south at 7:26 p.m., and it will set at 12:28 a.m. Mars is moving eastward, crossing the constellation of Aquarius this month. It’s currently at the western edge of Aquarius. Venus, now the brilliant morning star, will rise at 5:57 in the east southeast. It will grace our morning skies through next spring.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
11/06/2018 – Ephemeris – The Taurid meteor showers
Ephemeris for Election Day, Tuesday, November 6th. The Sun will rise at 7:27. It’ll be up for 9 hours and 57 minutes, setting at 5:24. The Moon, 1 day before new, will rise at 7:09 tomorrow morning.
We are in the midst of two showers of meteors that seen to come from the constellation of Taurus the bull. These are the Southern and Northern Taurids respectively. They only produce a handful of meteors per hour, but there seems to be some discrepancy in their peak dates. The International Meteor Organization has the Southern group peak October 10th. Other sources have it peak November 5th. The Northern group peaks on the 10th or 12th of November depending on the source. Anyway these are bits shed by Comet 2P/Encke, which has only a 3 year orbit of the Sun. Encke’s orbit also comes close to the Earth’s orbit where the Earth is at the end of June. I’ve always wondered if it was a piece of Encke’s nucleus that hit Siberia on June 30, 1908?
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The radiants are not as nearly defined as shown here
Bob Moler's Ephemeris Blog 