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02/27/2015 – Ephemeris – Previewing the month of March
Ephemeris for Friday, February 27th. The sun will rise at 7:24. It’ll be up for 11 hours and 3 minutes, setting at 6:27. The moon, 2 days past first quarter, will set at 4:08 tomorrow morning.
During March the increase in daylight hours are at its greatest, with Spring 3 weeks away. Daylight hours will increase from 11 hours and 9 minutes Sunday to 12 hours and 42 minutes on the 31st. Along with that the altitude of the sun at noon will increase from 38 degrees Sunday to 49 ½ degrees at month’s end. Local noon, by the way for Interlochen and Traverse City is about 12:50 p.m, which is mainly due to the fact that our standard time meridian happens to run through Philadelphia. That’s before daylight time starts in a bit more than a week. Then our time meridian will run by the eastern tip of Nova Scotia, so local noon, when the Sun is due south will occur at 1:50 p.m.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Star Chart for March 2015. Created using my LookingUp program.
The Moon is not plotted. The planets and stars are plotted for the 15th at 10 p.m. EDT. That is chart time.
Evening astronomical twilight ends at 8:07 p.m. EST on March 1st, increasing to 9:49 p.m. EDT on the 31st.
Morning astronomical twilight starts at 5:43 a.m. EST on March 1st, and decreasing to 5:45 a.m. EDT on the 31st. (Yes it is a decrease, thanks to the imposition of daylight time on March 8th)
Add a half hour to the chart time every week before the 15th and subtract and hour for every week after the 15th.
For a list of constellation names to go with the abbreviations click here.
The green pointer from the Big Dipper is:
- Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star.
- Drill a hole in the bowl of the Big Dipper and the water will drip on the back of Leo the Lion.
- Follow the arc of the Big Dipper’s handle to Arcturus
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 Standard Time on a 24 hour clock. Some additions made to aid clarity.
Conjunctions like the Moon-Saturn: 2.4° S means Saturn will appear 2.4° south of the Moon.
| Mar | 01 | Su | Venus: 30.1° E | |
| 05 | Th | 02:35 | Moon Apogee: 406,400 km | |
| 05 | Th | 13:05 | Full Moon | |
| 07 | Sa | 16:04 | Moon Ascending Node | |
| 12 | Th | 04:25 | Moon-Saturn: 2.4° S | |
| 13 | Fr | 13:48 | Last Quarter | |
| 13 | Fr | 21:39 | Moon South Dec.: 18.3° S | |
| 19 | Th | 15:38 | Moon Perigee: 357,600 km | |
| 20 | Fr | 05:36 | New Moon | |
| 20 | Fr | 05:46 | Total Solar Eclipse | |
| 20 | Fr | 18:45 | Vernal Equinox | |
| 20 | Fr | 22:19 | Moon Descending Node | |
| 21 | Sa | 18:13 | Moon-Mars: 1° N | |
| 22 | Su | 15:51 | Moon-Venus: 2.9° N | |
| 25 | We | 02:55 | Moon-Aldebaran: 0.9° S | |
| 26 | Th | 10:29 | Moon North Dec.: 18.2° N | |
| 27 | Fr | 03:43 | First Quarter |
02/26/2015 – Ephemeris – The strange month of February
Ephemeris for Thursday, February 26th. The sun will rise at 7:25. It’ll be up for 11 hours and 1 minute, setting at 6:26. The moon, 1 day past first quarter, will set at 3:21 tomorrow morning.
Let’s take a shot at why February is the shortest month. Blame the ancient Romans and their poor timekeeping skills. The Roman calendar was based on the Sun, or rather the seasons, what we would call the tropical year, rather than the Moon. With a lunar calendar it was easy to tell if it was off by a day or two. The Romans apparently started with a 12 month calendar starting in March with spring. Before the calendar reform of 45 BC months had alternating days of 29 and 31 except for February which had 28. That left them a bit short, so it appears that they added a month Intercalaris every few years or so to fix it. That eventually came down to adding a day to February every 4 years to fix the problem.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Look quick! A new comet escapes the Sun
A sun grazing comet was discovered in SOHO chronograph images. And unlike Comet ISON 15 months ago which checked in but didn’t check out. This one escaped to possibly become visible in our evening sky. It was the 2875th comet discovered on SOHO chronograph images. Usually it ends there, but the comet, now named C/2015 D1 (SOHO).
Hot off the press. Comet 2015 D1 was part of the download of comet elements this afternoon. Here’s the track with estimated magnitudes for tonight and the next week. Created using Cartes du Ceil (Sky Charts).
A more comprehensive post from Universe Today is here.
02/25/2015 – Ephemeris – It’s planet day on Ephemeris
Ephemeris for Wednesday, February 25th. The sun will rise at 7:27. It’ll be up for 10 hours and 57 minutes, setting at 6:24. The moon, at first quarter today, will set at 2:28 tomorrow morning.
Lets take a look at the bright planets and a fading binocular comet for this week. Brilliant Venus is in the west-southwest by 7 p.m. It will set at 8:55 p.m. It’s separating from Mars which appears below and right of it. The Red Planet will set tonight at 8:46 p.m. Jupiter will appear In the southeastern sky in the evening. It will be up just about all night, and will set at 6:44 a.m. It’s near the sickle-shaped head of Leo the lion, and it’s the brightest star-like object in the sky. Early risers will be able to spot Saturn which will rise in the east-southeast at 1:48 a.m. It’s in the south at 6 a.m. Comet Lovejoy, visible in binoculars, is about half way from the star at the end of Andromeda, called Almaak and the “W” of Cassiopeia.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus and Mars low in the west after sunset. This is 7 p.m., February 25, 2015. Created using Stellarium.
Jupiter with the first quarter moon and the winter stars at 9 p.m., February 25, 2015. Created using Stellarium.
Closeup of the Moon and Aldebaran at 9 p.m. on February 25, 2015. They appeared their closest at 6 p.m. They might be glimpsed with binoculars or a small telescope at that time.
Jupiter and it’s moons at 9 p.m. February 25, 2015. Note that at this time the Great Red Spot is on the face if Jupiter. Created using Cartes du Ciel (Sky Charts).
Looking southward at Saturn and a preview of the summer constellations at 6 a.m. February 26, 2015. Created using Stellarium.
What Saturn and its moons might appear like in a telescope at 6 a.m., February 26, 2015. Small telescopes will show only the moon Titan. Created using Cartes du Ceil (Sky Charts).
The track of Comet 2014 Q2 (Lovejoy) from 2/25/15 to 03/03/15 which will appear high in the west at 9 p.m. The comet is approaching Cassiopeia. The comet is dropping below binocular visibility, so this is the last time I will cover it on this blog. Created using Cartes du Ceil (Sky Charts).
02/24/2015 – Ephemeris – Not all greatest elongations of Mercury are equal
Ephemeris for Tuesday, February 24th. The sun will rise at 7:29. It’ll be up for 10 hours and 54 minutes, setting at 6:23. The moon, 1 day before first quarter, will set at 1:28 tomorrow morning.
Today Mercury is at its greatest distance west of the Sun. Don’t go out to view Mercury right before sunrise unless you’re way south of here, or better yet south of the equator. Because of the tilt of the Earth’s axis and our latitude the positions of the planets that appear near the sun at sunrise and sunset are easier or harder to spot depending on the season. The best time to spot Mercury when it’s at its greatest elongation or distance east of the Sun is on late winter and spring evenings, or late summer and autumn mornings when Mercury is west of the Sun. Since the seasons south of the equator are opposite ours the same rule holds. It’s late summer down there which is favorable to spot Mercury in the morning, but not here.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mercury at greatest western elongation on late a winter morning. Mercury is off to the side of the Sun and quite low. This is a poor elongation for us in the northern hemisphere. Created using Stellarium.
Mercury at greatest western elongation on an autumn morning. Mercury is above the Sun and quite high. This is a good elongation for us in the northern hemisphere. Created using Stellarium.
02/23/2015 – Ephemeris – The Launch of the DSCOVR satellite
Ephemeris for Monday, February 23rd. The sun will rise at 7:30. It’ll be up for 10 hours and 51 minutes, setting at 6:22. The moon, 2 days before first quarter, will set at 12:24 tomorrow morning.
On Wednesday the 11th the DSCOVR satellite was launched to a special point between the Earth and the Sun called the Lagrangian point 1 or the Earth-Sun L1 point. It’s a point of gravitational equilibrium between the Earth and the Sun, about a million miles sun-ward of the Earth, or four times the distance of the Moon. It will take the craft over 100 days to get there, which it will slowly orbit. It will act as an early warning sentinel, replacing the aging ACE spacecraft. It will give us about an hour’s warning of incoming coronal mass ejections or CMEs erupting from the Sun. It also has an earth pointing camera with various filters pointed to the full earth and occasionally the far side of the new Moon.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
SpaceX Falcon 9 V1.1 first stage burns to launch DSCOVR to the Earth-Sun L1 point. Credit: NASA. Click to enlarge.
Click to enlarge
Earth-Sun Lagrangian Points. Source: Wikimedia Commons, Xander89. Click to enlarge.
02/20/2015 – Ephemeris – The Moon joins Venus and Mars in the west tonight
Ephemeris for Friday, February 20th. The sun will rise at 7:35. It’ll be up for 10 hours and 42 minutes, setting at 6:17. The moon, 2 days past new, will set at 8:49 this evening.
Tonight the two day old moon will be seen in the west in a tight triangle with Venus and Mars. They will become visible about 7 o’clock. The planets will be to the left of the Moon with much dimmer Mars above Venus. The formation is tight enough that the motion of the moon will be evident between 7 and when the Moon sets at 8:49. The moon moves its own diameter in about an hour. The moon will also exhibit earthshine, the reflection of the bright earth in the moon’s sky on the night side of the Moon itself. The earthshine lit part of the moon shows a ghostly man in the moon image we are familiar with at full moon. This earthshine is visible on the Moon for a few days before new moon to a few days after new moon.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Views of the Venus, Mars, Moon grouping from three locations.
Appearance of the grouping from northern Michigan, US
Venus and Mars with the Moon at 7 p.m. EST on February 20, 2015. This is for northern Michigan. Created using Stellarium.
Appearance of the grouping from Los Angeles, CA
Venus and Mars with the Moon at 8 p.m. PST on February 20, 2015. This is for Los Angeles, CA. Created using Stellarium.
Appearance of the grouping from London, UK
Venus and Mars with the Moon at 20:28 GMT on February 20, 2015. This is for London, UK. Created using Stellarium.
02/19/2015 – Ephemeris – What’s a conjunction?
Ephemeris for Thursday, February 19th. The sun will rise at 7:37. It’ll be up for 10 hours and 39 minutes, setting at 6:16. The moon, 1 day past new, will set at 7:32 this evening.
Saturday night* Venus will be in conjunction with Mars. To me the best sight will be tomorrow night when the thin crescent moon will join the two planets in a very picturesque triangle. Conjunctions are terms shared between astronomers and astrologers and why shouldn’t they be, astrology is, in my opinion, astronomy’s illegitimate parent. To astronomers conjunctions are when two solar system objects are directly north and south of each other (the same right ascension). Astrologers have the conjunction on the same date, but most will say it’s occurring in Aries. Astronomers in the other hand can see that the two planets are now seen against the stars of western Pisces. Most astrologers don’t recognize the precession of the earth’s axis, it’s 26,000 year wobble in their calculations.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* As reported in the radio program it was Sunday. However the two planets appear closest Saturday night. 7 p.m. EST ( UT – 5 hr) on the 21st is actually 0 hr UT on the 22nd (Sunday).
Addendum
Venus and Mars in conjunction at 7 p.m. EST February 21, 2015. Created using Stellarium.
The big picture: In a conjunction planets simply happen to appear along a line of sight from the Earth. They have nothing to do with each other. This is the location of the planets Earth, Venus and Mars on February 22, 2015. Created using Celestia.
Below see the shift of the vernal equinox or first point of Aries, as it’s sometimes called has shifted from 150 CE in Ptolemy’s day to today.
The vernal equinox in 150 CE. Note that Aries to the left. The Sun travels on the ecliptic line (The diagonal line) from right to left. Created using Cartes du Ciel (Sky Charts).
The vernal equinox today, in 2015 CE. Note that Aries has slid off to the left. The Sun travels on the ecliptic line (The diagonal line) from right to left. Created using Cartes du Ciel (Sky Charts).
02/18/2015 – Ephemeris – Wednesday is bright planet day (or night) on Ephemeris
Ephemeris for Ash Wednesday, Wednesday, February 18th. The sun will rise at 7:38. It’ll be up for 10 hours and 36 minutes, setting at 6:15. The moon is new today, and won’t be visible.
Lets take a look at the bright planets and a fading binocular comet for this week. Brilliant Venus is in the west-southwest by 7 p.m. It will set at 8:37 p.m. It’s nearing Mars which appears above and left of it. They will be at their closest on the 22nd. The Red Planet will set tonight at 8:45 p.m. Jupiter will appear In the southeastern sky in the evening. It will be up all night, and will set at 7:14 a.m. It’s near the sickle-shaped head of Leo the lion, and it’s the brightest star-like object in the sky. Early risers will be able to spot Saturn which will rise in the east-southeast at 2:15 a.m. Comet Lovejoy, visible in binoculars, is about half way from the star at the end of Andromeda, called Almaak and the “W” of Cassiopeia.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus and Mars low in the west after sunset. This is 7 p.m., February 18, 2015. Created using Stellarium.
Venus, Mars and the moon on Friday night at 7 p.m. (2/20/15). Created using Stellarium.
Jupiter with the winter constellations at 9 p.m., February 18, 2015. Created using Stellarium.
Jupiter and it’s moons at 9 p.m. February 18, 2015. Note that at this time the Great Red Spot is on the face if Jupiter. Created using Cartes du Ciel (Sky Charts).
The track of Comet 2014 Q2 (Lovejoy) from 2/18/15 to 02/24/15 which will appear high in the west at 9 p.m. On the 20th the comet will pass near M76, a 10th magnitude planetary nebula. It will be much dimmer than the comet. Created using Cartes du Ceil (Sky Charts).
Looking southward at 6 a.m. February 19, 2015 to a preview of the constellations of summer with Saturn in the south and Jupiter setting in the west. Click to enlarge.
What Saturn and its moons might appear like in a telescope at 6 a.m., February 19, 2015. Small telescopes will show only the moon Titan. Created using Cartes du Ceil (Sky Charts).
02/17/2015 – Ephemeris – There are no unicorns except in the heavens
Ephemeris for Fat Tuesday, Tuesday, February 17th. The sun will rise at 7:40. It’ll be up for 10 hours and 33 minutes, setting at 6:13. The moon, 1 day before new, will rise at 7:07 tomorrow morning.
Among all the constellations in the sky of animals real and mythical, there is also a unicorn. It’s called Monoceros, and inhabits the southeastern sky at 9 p.m. bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left. Unfortunately for observers without optical aid Monoceros, though large, is devoid of any but the faintest stars. Maybe that’s why no one sees unicorns anymore. It has many faint stars because the Milky Way runs through it. To the telescope it is a feast of faint nebulae or clouds of gas and dust, the birth place of stars, including the red rose of the Rosette Nebula, and the strange and tiny Hubble’s Variable Nebula. It contains no bright stars, but it has wonders for the telescope.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The constellation Monoceros the unicorn. Created using Cartes du Ciel (Sky Charts). Click to enlarge.
Can you see a unicorn here? Me neither.
One thing I didn’t mention in the program is the star labeled β. It is a triple star in telescopes.
Universe Today has a great post on Monoceros by Tammy Plotner, who by sad coincidence passed away a few days ago.
Bob Moler's Ephemeris Blog 