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Ephemeris: 07/03/2025 – The Sun is farthest away today
This is Bob Moler with Ephemeris for Thursday, July 3rd. Today the Sun will be up for 15 hours and 29 minutes, setting at 9:31, and it will rise tomorrow at 6:03. The Moon, 1 day past first quarter, will set at 1:36 tomorrow morning.
This afternoon at 5:59 PM, the Earth will reach aphelion from the Sun, the farthest it gets from it during the year. Earth will be 94 and a half million miles away from the Sun, a bit farther than our normal 93 million. In a planet’s orbit of the Sun, the Earth is no exception, it moves slowest when farthest from the Sun than when it’s nearest. It doesn’t make much difference in the amount of heat we get from the Sun being only 1½% farther than average. But it makes summer the longest season at 94 days, versus winter’s 89 days. OK, I know it doesn’t feel like it here in Northern Michigan, but count the days between each solstice and the next equinox.
The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 07/04/2024 – The Earth at aphelion
This is Ephemeris for Independence Day, Thursday, July 4th. Today the Sun will be up for 15 hours and 27 minutes, setting at 9:31, and it will rise tomorrow at 6:03. The Moon, 1 day before new, will rise at 5:10 tomorrow morning.
Tomorrow morning at 1:59 AM , actually overnight tonight, the Earth will reach aphelion from the Sun, the farthest it gets from it during the year. Earth will be 94 and a half million miles away from the Sun, a bit farther than our normal 93 million. In a planet’s orbit of the Sun, the Earth is no exception, it moves slowest when farthest from the Sun than when it’s nearest. It doesn’t make much difference in the amount of heat we get from the Sun being only 1 1/2% farther than average. But it makes summer the longest season at 94 days, versus winter’s 89 days. OK, I know it doesn’t feel like it here in Northern Michigan, but count the days between each solstice and the next equinox.
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
07/06/2023 – Ephemeris – Today the Earth is farther from the Sun than anytime this year
This is Ephemeris for Thursday, July 6th. Today the Sun will be up for 15 hours and 26 minutes, setting at 9:30, and it will rise tomorrow at 6:04. The Moon, halfway from full to last quarter, will rise at 12:16 tomorrow morning.
Today, the Sun is at its farthest distance from the Earth. It’s called aphelion. The exact time actually occurred at 4:59 this morning at a distance of 94 and a half million miles away. Because of the gravitational pull of the Moon and planets on the Earth, especially Jupiter and Venus and gravitational pull of the planets, especially Jupiter on the Sun, the aphelion and perihelion, the closest date in January don’t occur on the same date or same distance every year. The date wanders by a day or two each year. The entire distance variation of the Earth from the Sun is plus or minus 1.5 million miles (2.4 million kilometers) over the year, makes summer the longest season by a few days because the Earth moves slower when farther from the Sun, than when it is nearer.
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.
Note: Apoapsis and Periapsis are generic terms for the farthest and nearest points in an orbit to the central body. For a body orbiting the Sun, it’s aphelion and perihelion. For a satellite of the Earth, it’s apogee and perigee.
07/05/2021 – Ephemeris – Happy Aphelion Day
This is Bob Moler with Ephemeris for Monday, July 5th. Today the Sun will be up for 15 hours and 27 minutes, setting at 9:30, and it will rise tomorrow at 6:04. The Moon, halfway from last quarter to new, will rise at 3:24 tomorrow morning.
Today, the Moon and Sun are at their farthest from the Earth. For the Moon it’s called apogee, for the Sun it’s called aphelion. At 10:48 this morning the Moon will be at that point 251,842 miles (405,300 kilometers) away. The Sun will be farthest at 10:59 pm at a distance of 94 million, 452 thousand miles (152 million, 6 thousand kilometers) away. Because of the gravitational pull of the Moon and planets on the Earth, and the Pull of the planets, especially Jupiter on the Sun, the aphelion and perihelion or closest date in January don’t occur on the same date or same distance every year. The date wanders by a day or two each year. The entire distance variation for the Earth is plus or minus 1.5 million miles (2.4 million kilometers) over the year, but makes summer the longest season by a few days because the Earth moves slower when farther from the Sun, than when it is nearer.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4). They may be different for your location.
Addendum
The Earth’s orbital ellipse, somewhat exaggerated, showing perihelion, aphelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.
Currently, summer is the longest season at 93.65 days, while winter is the shortest season at 88.99 days. (Source: Astronomical Tables of the Sun, Moon and Planets, Third Edition by Jean Meeus)
07/04/2019 – Ephemeris – Happy Independence Day, at our farthest from the Sun
Ephemeris for Independence Day, Thursday, July 4th. Today the Sun will be up for 15 hours and 28 minutes, setting at 9:31, and it will rise tomorrow at 6:03. The Moon, 2 days past new, will set at 11:20 this evening.
Today, Independence Day the Earth is at its greatest distance, aphelion, from the sun or about 94.5 million miles (152.2 million km) from the Sun. It doesn’t do much to weaken the strength of sunlight, as you will find out when you go to the beach. But, occurring in summer, it makes summer the longest season by a several days over winter. Our calendar tries to keep up with the seasonal or tropical year, while the Earth’s revolution from its farthest or aphelion point to the next is slightly longer. Back in 1776, at the founding of our nation, the Earth was farthest from the Sun on June 30th. As we go more centuries into the future our summer will even get a bit longer. But remember the poor Australians, and others in the southern hemisphere, whose winter will also get longer.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Earth’s elliptical orbit, somewhat exaggerated, showing perihelion, aphelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.
07/05/2018 – Ephemeris – Earth will be the farthest from the Sun in its orbit tomorrow
Ephemeris for Thursday, July 5th. Today the Sun will be up for 15 hours and 27 minutes, setting at 9:30, and it will rise tomorrow at 6:04. The Moon, 1 day before last quarter, will rise at 1:39 tomorrow morning.
At just before noon tomorrow the Earth will reach the aphelion point in its orbit of the Sun reaching 94.48 million miles from our star. The is a bit farther than the Earth was at its perihelion point in early January of 91.32 million miles. This doesn’t affect the total amount of heat the Earth gets from the Sun, as could be felt in the last week. The big temperature differences are due to the seasons, which are caused by the tilt of the Earth’s axis with respect to its orbit. However having aphelion in summer, when the Earth moves it slowest around the Sun makes summer the longest season. It’s 4 days longer than winter. I know it doesn’t feel like it in northern Michigan, especially with the April we had this year.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Earth’s orbit, somewhat exaggerated, showing aphelion and the seasons. Credit “Starts with a Bang” blog by Ethan Siegel.
The exact date and distance of aphelion and perihelion change by a few days and a few thousand miles every year. The Earth’s orbit of the Sun is also affected by the other planets of the solar system, principally Venus and Jupiter.
07/03/2017 – Ephemeris – The Earth is farthest from the Sun today
Ephemeris for Monday, July 3rd. Today the Sun will be up for 15 hours and 28 minutes, setting at 9:30, and it will rise tomorrow at 6:03. The Moon, 3 days past first quarter, will set at 3:13 tomorrow morning.
At 8:59 tonight the Earth will pass a point in its orbit of the sun called aphelion, the farthest point from the sun of 94.5 million miles (152 million km). The whole Earth gets something like 6% less heat from the Sun than early January when the Sun is closest. So why is it summer now? The difference in distance from the sun pales as a cause of the seasons next to the tilt of the earth’s axis. Six months ago, because the sun was up for a shorter period each day, and didn’t rise very high in the sky, the sun gave us in northern Michigan something like 70% less heat than it does now. The real effect of aphelion coming in summer is that it makes summer the longest season at 94 days. This is because the farther the Earth is from the Sun, the slower it travels. Hey, it’s summer – take the hint and slow down and enjoy the season.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
06/20/2016 – Ephemeris – Summer will start later today
Ephemeris for Monday, June 20th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:31, and it will rise tomorrow at 5:57. The Moon, at full today, will rise at 9:32 this evening.
Well, this is it, the last 12 hours of spring. Summer will begin at 6:35 this evening. In the southern hemisphere the season of winter will begin, and the south pole of the Earth will begin* is in the middle of its six months of darkness. The north above 66 ½ degrees north latitude is the land of the midnight Sun. Over summer that line will creep northward as the Sun heads southward. The seasons are caused by the tilt of the Earth’s axis, not by the Earth’s change in distance from the Sun. In fact we are approaching our farthest distance from the Sun, of about 94.5 million miles (152 million km) on the fourth of July called aphelion. The greater than normal distance makes summer the longest season at 93.7 days, winter being the shortest at 89 days.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* Thanks to Jeff Silagy for spotting the error.
Addendum
The sun’s daily path through the sky from horizon to horizon on the first day of summer, the summer solstice. Credit My LookingUp program.
Earth from the DSCOVR satellite at the June solstice 2015. Credit NOAA.
07/06/2015- Ephemeris – Today we are at our greatest distance from the sun.
Ephemeris for Monday, July 6th. Today the Sun will be up for 15 hours and 26 minutes, setting at 9:30. The Moon, 2 days before last quarter, will rise at 12:23 tomorrow morning and tomorrow the Sun will rise at 6:04.
This is the day the we are the farthest we can get from the Sun for the year. The point in the Earth’s orbit that it occurs is called aphelion. Earth is closest to the Sun in January at perihelion. The actual distance difference between perihelion and aphelion is 3 million miles out of roughly 93 million miles. So now we’re roughly 94 and a half million miles from the Sun or 152 million kilometers., and will swoop down to 91 and a half million miles(91.4) or 147 kilometers from the Sun in early January. Because Earth’s northern and southern hemispheres have different ratios and placement of land versus ocean I’m not sure you could correlate seasonal differences of the hemispheres with the Earth’s distance from the Sun. Anyway the approximate time we reach aphelion will be 3 p.m. EDT (19 hr UT).
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The orbits of the inner planets. (P)erihelion – (A)phelion
The above is a diagram from three years ago, so the planets other than the Earth will be in different positions today. The date of aphelion and perihelion move around over a greater range of dates than the equinoxes and solstices. I’m not sure why without researching it, but I suspect that the Moon has something to do with it.
07/02/2015 -Ephemeris – A belated preview of July’s skies
Ephemeris for Thursday, July 2nd. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:31. The Moon, 1 day past full, will rise at 9:48 this evening and tomorrow the Sun will rise at 6:02.
Lets preview July’s skies a day late. Sorry, it’s been a busy week.. The sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 30 minutes Today to 14 hours 44 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the sun at local noon, when the sun is due south will decrease from 68 degrees Now to 63 degrees at month’s end. The sun will be a degree lower in the Straits area. Despite the warmth, the earth will reach its greatest distance from the sun on Monday the 6th. The range of the earth’s distance from the sun is 3 million out of 93 million miles.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Star Chart for July 2015. Created using my LookingUp program. Click on image to enlarge.
The Moon is not plotted.
The planets and stars are plotted for the 15th at 11 p.m. EDT. That is chart time. Note, Traverse City is located 1 hour 45 minutes behind our time meridian. To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.
Evening Astronomical twilight ends at midnight. EDT on July 1st, decreasing to 11:14 p.m. EDT on the 31st.
Morning astronomical twilight starts at 3:32 a.m. EDT on July 1st, and increasing to 4:42 a.m. EDT on the 31st.
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
- Continue with a spike to Spica
- The Summer Triangle is shown in red
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 Daylight Time on a 24 hour clock. Some additions made to aid clarity.
Conjunctions like the Moon-Jupiter: 4.5° N means Jupiter will appear 4.5° north of the Moon.
Date Local Event
Time
Jul 01 We 02:48 Moon South Dec.: 18.4° S
01 We Venus: 42.4° E
01 We 22:20 Full Moon
05 Su 14:54 Moon Perigee: 367100 km
06 Mo 08:59 Aphelion: 1.0167 AU
07 Tu 20:07 Moon Descending Node
08 We 16:24 Last Quarter
12 Su 13:55 Moon-Aldebaran: 0.9° S
14 Tu 00:24 Moon North Dec.: 18.4° N
14 Tu 17:35 Venus-Regulus: 2.3° S
15 We 21:24 New Moon
18 Sa 13:34 Moon-Jupiter: 4.5° N
18 Sa 21:06 Moon-Venus: 0.5° N
21 Tu 07:02 Moon Apogee: 404800 km
21 Tu 15:32 Moon Ascending Node
23 Th 15:18 Mercury Superior Conjunction with the Sun
24 Fr 00:04 First Quarter
26 Su 04:43 Moon-Saturn: 2.4° S
28 Tu 10:23 Delta Aquarid Meteor Shower: ZHR* = 20
28 Tu 13:34 Moon South Dec.: 18.3° S
31 Fr 06:43 Full Moon
Aug 01 Sa Venus: 21.5° E
*ZHR – Zenithal Hourly Rate: Approximate number of meteors per hour when the shower radiant is at the zenith. For more information on this and other meteor showers in 2015 see the International Meteor Organization website calendar section: http://www.imo.net/calendar.
Bob Moler's Ephemeris Blog 