Bob Moler's Ephemeris Blog

This is Ephemeris for Pi Approximation Day, Wednesday, July 22nd, that is 22/7ths. Today the Sun will be up for 15 hours and 1 minute, setting at 9:19, and it will rise tomorrow at 6:19. The Moon, 1 day past first quarter, will set at 1:04 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 9:45 PM tonight, nearly a half-hour after sunset, Venus will be easily spotted in the western sky. A telescope will show a tiny gibbous disc of Venus. It is now closer than the Sun, at 81.8 million miles (131.6 mil km) away from us. Over the next nearly 3 months it will be moving closer to us and becoming much larger. In the morning, Saturn and Mars will be visible, in the southeast and east respectively. The Earth is now chasing down Mars, and later this year the launch window will open to send spacecraft to the Red Planet. Mars will be closest to the Earth and opposite the sun in the sky next February.

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

This is Ephemeris for Wednesday, July 15th. Today the Sun will be up for 15 hours and 13 minutes, setting at 9:25, and it will rise tomorrow at 6:12. The Moon, 1 day past new, will set at 10:35 this evening. | Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10 PM tonight, a half-hour after sunset, Venus will be easily seen in the western sky. A telescope will show a very tiny gibbous disc of Venus because it is now closer than the Sun, at 86.9 million miles (139.9 million kilometers) away from us. Over the next nearly 3½ months, it will be moving closer to us and becoming much larger. In the morning, Saturn and Mars will be visible in the southeast and east, respectively. The Earth is now chasing down Mars, and later this year the launch window will open to send spacecraft to the Red Planet. Mars will be next closest to the Earth and opposite the sun in the sky next February.

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

This is Ephemeris for Wednesday, July 8th. Today the Sun will be up for 15 hours and 23 minutes, setting at 9:29, and it will rise tomorrow at 6:06. The Moon, 1 day past last quarter, will rise at 1:26 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10 PM tonight, a half-hour after sunset, Venus will be easily seen in the western sky. A telescope will show a very tiny gibbous disc of Venus, because it is just a little bit closer than the Sun, at 92.0 million miles (148 million kilometers) away from us. Over the next nearly 3½ months, it will be moving closer to us and becoming much larger. In the morning, Saturn and Mars will be visible, in the southeast and east respectively. The Earth is now chasing down Mars, and later this year the launch window will open to send spacecraft to the Red Planet. Mars will be next closest to the Earth and at opposition with the sun in February next year.

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

This is Ephemeris for Wednesday, July 1st. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:32, and it will rise tomorrow at 6:01. The Moon, 2 days past full, will rise at 11:01 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10:30 PM tonight, nearly an hour after sunset, Venus is easily seen in the western sky, with Jupiter barely above the horizon, and may not be visible. A telescope will show a very tiny gibbous disc of Venus, because it is still pretty much beyond the Sun, 97 million miles (156 million kilometers) away from us. Over the next nearly 4 months it will be moving closer to us and becoming much larger. In the morning, Saturn will rise at 1:41 AM, followed by dimmer Mars nearly 2 hours later. The Earth is now chasing down Mars, and later this year the launch window will open to send spacecraft to the Red Planet. Mars will be next closest to the Earth in February next year.

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

This is Ephemeris for Wednesday, June 24th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:32, and it will rise tomorrow at 5:58. The Moon, 3 days past first quarter, will set at 2:36 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10:30 PM tonight, nearly an hour after sunset, Venus and Jupiter are seen in the western sky, with Jupiter below and right of the brighter Venus. Mercury, though being just above the horizon at that time, is completely overcome by the twilight. A telescope will show a very tiny gibbous disc of Venus, because it is still pretty much beyond the Sun, 102 million miles (164 million kilometers) away from us. Over the next 4 months it will be moving closer to us and becoming much larger. In the morning, Saturn will rise at 1:52 AM, followed by dimmer Mars nearly 2 hours later. The Earth is now chasing down Mars, and soon the launch window will open to send spacecraft to the Red Planet.

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

This is Ephemeris for Wednesday, June 17th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:31, and it will rise tomorrow at 5:56. The Moon, 3 days past new, will set at 12:09 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10:15 PM tonight, nearly an hour after sunset, Venus and Jupiter, and even Mercury may be seen in the western sky, with Jupiter below and right of the brighter Venus, and Mercury below and right of Jupiter. Jupiter appears to be chasing Mercury back toward the sun. But Mercury is getting dimmer, and will soon be lost in the twilight glow. A telescope will show a very tiny disc on Venus, because it is still pretty much beyond the Sun, 106 million miles (171 mil km) away from us. Over the next 4 months it will be moving closer to us and becoming much larger. In the morning, Saturn will rise at 2:37 AM, followed by dimmer Mars an hour and a half later.

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

This is Ephemeris for Wednesday, June 10th. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:27, and it will rise tomorrow at 5:56. The Moon, 2 days past last quarter, will rise at 3 o’clock tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10:15 PM tonight, nearly an hour after sunset, Venus and Jupiter may be seen in the western sky, with the brighter Venus above Jupiter. A telescope will show a very tiny disc on Venus, because it is still pretty much beyond the Sun, 111 million miles (179 million kilometers) away from us. Over the next 4 1/2 months it will be moving closer to us and becoming much larger. Mercury is marginally visible below and right of Venus and Jupiter. Jupiter now sets at 11:52 PM, with Venus setting ten minutes later. Saturn will rise into the eastern sky at 3:04 AM, followed by dimmer Mars an hour later.

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

This is Ephemeris for Wednesday, June 3rd. Today the Sun will be up for 15 hours and 23 minutes, setting at 9:23, and it will rise tomorrow at 5:58. The Moon, 3 days past full, will rise at 12:29 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10:15 PM tonight, nearly an hour after sunset, Venus and Jupiter may be seen in the western sky. A telescope will show a very tiny disc on Venus, because it is still pretty much beyond the Sun, 115 million miles (186 million kilometers) away from us. Over the next 4½ months it will be moving closer to us and becoming much larger. Jupiter is to the upper left of Venus, and the second-brightest star-like object in the sky. Venus will set at 12:05 AM, while Jupiter will hold out ten minutes longer. Venus will pass Jupiter on the afternoon of the 9th. Saturn rises into the eastern sky at 3:27 AM, followed by dimmer Mars an hour later.

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

This is Bob Moler with Ephemeris for Wednesday, May 27th. Today the Sun will be up for 15 hours and 13 minutes, setting at 9:17, and it will rise tomorrow at 6:02. The Moon, halfway from first quarter to full, will set at 4:08 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 10 PM tonight, about 40 minutes after sunset, Venus may be seen in the western sky. A telescope will show a very tiny disc on Venus, because it is still pretty much beyond the Sun, 120 million miles (193 million km) away from us. Over the next 5 months it will be moving closer to us and becoming much larger. Jupiter is the second-brightest star-like object in the western sky seen before 10 PM. It is above and left of Venus tonight. Venus will set at 12:04 AM, while Jupiter will hold out until 12:41 AM. Saturn rises in the east at 3:52 AM, followed by dimmer Mars at 4:42 AM.

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

This is Ephemeris for Wednesday, May 20th. Today the Sun will be up for 15 hours exactly, setting at 9:09, and it will rise tomorrow at 6:08. The Moon, 3 days before first quarter, will set at 1:41 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 9:30 PM tonight, about 20 minutes after sunset, Venus may be seen in the western sky. A telescope will show a very tiny disc on Venus, because it is still pretty much beyond the Sun, 124 million miles (199 million kilometers) away from us. Over the next 5 months it will be moving closer to us and becoming much larger. Jupiter is the second-brightest star-like object in the western sky seen before 10 PM. It is below and right of the Moon tonight. Venus will set at 11:53 PM, while Jupiter will hold out until 1:01 AM. Saturn may be first glimpsed just after it rises in the east at 4:18 AM, before morning twilight overwhelms it later on.

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