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07/19/2019 – Ephemeris – 50 years ago tomorrow humankind set foot on the Moon

July 19, 2019 Leave a comment

Ephemeris for Friday, July 19th. Today the Sun will be up for 15 hours and 7 minutes, setting at 9:22, and it will rise tomorrow at 6:16. The Moon, 3 days past full, will rise at 11:14 this evening.

On this day, 50 years ago the combined Apollo 11 spacecraft Command and Service module with attached Lunar Module dropped into orbit of the Moon. The crew spotted a glow coming from the Aristarchus region, still on the night side of the Moon. Armstrong and Aldrin entered the LM to power it up and to get it ready for landing. The next day they undocked from the Command Module and began their 2 hour 33 minute descent to the Moon’s surface. As they neared the surface The astronauts found out they were going to miss the planned landing area and would land in a more boulder strewn area. Armstrong took control and guided the LM to a safe landing with less than 30 seconds of fuel remaining. The Eagle had landed.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Crew of Apollo 11

Left to right Neil Armstrong, Mission Commander; Michael Collins, Command Module Pilot; and Buzz Aldrin, Lunar Module Pilot. Credit: NASA.

Apollo 11 launch

The Saturn V for the Apollo 11 mission lifts of from Pad 39A. Credit: NASA.

Aldrin with the PSEP instrument looking back at the LM. Credit NASA/Neil Armstrong.

Lunar Reconnaissance Orbiter image of the Apollo 11 landing area. Compare the location od the objects in the picture above with this image.  The flag was blown down by the lift off of the Ascent module when the Astronauts left the Moon. Credit NASA/LRO.

07/16/2019 – Ephemeris – 50 years ago today the Apollo mission left for the Moon

July 16, 2019 Comments off

Ephemeris for Tuesday, July 16th. Today the Sun will be up for 15 hours and 12 minutes, setting at 9:25, and it will rise tomorrow at 6:13. The Moon, at full today, will rise at 9:30 this evening.

50 years ago today at 11:32 a.m. Eastern Daylight Time the most powerful rocket ever built roared into life. The Saturn V, a three stage rocket, 363 feet tall, which in turn launched two spacecraft, the Command and Service modules, and the Lunar Module, and three astronauts on their journey to destiny, Neil Armstrong, Edwin (Buzz) Aldrin, and Michael Collins. It was the start of the Apollo 11 mission. It happens that tonight the namesake of the rocket, the planet Saturn is to the right of the Moon. At launch the Moon was two days old, a thin crescent in the west that evening. Four days later they would be orbiting the Moon, and Armstrong and Aldrin would be descending to the Moon’s surface.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addenda

Apollo 11

Crew of Apollo 11

Left to right Neil Armstrong, Mission Commander; Michael Collins, Command Module Pilot; and Buzz Aldrin, Lunar Module Pilot. Credit: NASA.

Apollo 11 launch

The Saturn V for the Apollo 11 mission lifts of from Pad 39A. Credit: NASA.

The Moon and Saturn tonight

The Moon and Saturn tonight, 11 p.m. July 16, 2019. In reality the Moon will be so bright that Saturn will be almost overwhelmed. Created using Stellarium.

Here’s an excellent podcast series from the BBC:  13 Minutes to the Moon.

Partial Lunar Eclipse

The partial lunar eclipse today is not mentioned in the program because it is not visible locally.

Partial Lunar Eclipse of July 16, 2019. Click on image to enlarge. Credit NASA/GSFC/F. Espenak.

07/15/2019 – Ephemeris – The Apollo 1 tragedy

July 15, 2019 Comments off

Ephemeris for Monday, July 15th. Today the Sun will be up for 15 hours and 14 minutes, setting at 9:25, and it will rise tomorrow at 6:12. The Moon, 1 day before full, will set at 5:48 tomorrow morning.

On January 27th, 1967 the crew of Apollo 1 were running a dress rehearsal of their upcoming launch. On board were Gus Grissom, veteran of the Mercury and Gemini programs, Ed White the first American to walk in space on Gemini 4, and rookie astronaut Roger Chaffee from my home town of Grand Rapids, Michigan. Five and a half hours after the test started one of the crew called out “Fire in the cockpit”. In a very few minutes the astronauts were dead. They were running in a pure oxygen atmosphere at a bit above atmospheric pressure and a spark may have ignited the flammable materials in the spacecraft. The accident delayed the program nearly 2 years as the capsule was redesigned.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Apollo 1 crew

Left to right: Virgil I. (Gus) Grissom, veteran of the second Mercury flight and Gemini 3, the first manned Gemini flight; Edward H. White first American space walker on Gemini 4, and rookie Roger B. Chaffee. Credit: NASA.

Apollo 1 spacecraft after the fire

The outside of the Apollo 1 capsule after thr fire that took the three astronaut’s lives. Credit: NASA.

06/11/2019 – Ephemeris – The crater Copernicus on the Moon

June 11, 2019 Comments off

Ephemeris for Tuesday, June 11th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:28, and it will rise tomorrow at 5:56. The Moon, 1 day past first quarter, will set at 3:26 tomorrow morning.

Tonight, visible on the waxing gibbous Moon in binoculars or a small telescope the terminator, the sunrise line crosses the prominent crater Copernicus. This crater is nearly half way from the top to the bottom of the Moon. It is 56 miles (93 km) in diameter and 2 miles (3.5 k m) deep. The low Sun angle accentuates the depth of the crater. As large craters goes, Copernicus is rather new, being somewhat younger than 1.1 billion years old, a quarter of the Moon’s age. A dramatic image taken by the Lunar Orbiter spacecraft in 1966, in preparation for the Apollo lunar landings of an oblique view of the crater peeking over a crater wall was, at that time, dubbed the Picture of the Century”.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Binocular Moon

The Moon tonight, June 11, 2019 showing the crater Copernicus. Created using Virtual Moon Atlas.

Closeup of Copernicus

Closeup of Copernicus with the small double crater Fauth south of it. Created using Virtual Moon Atlas.

Picture of the Century

Picture of the Century taken by the lunar Orbiter 2. Copernicus in an oblique photo from the south. Not the double crater Fauth at the bottom of the Image. Credit: NASA/Lunar Orbiter Image Recovery Project (LOIRP).

06/06/2019 – Ephemeris – The 75th anniversary of D-Day, the astronomical connection

June 6, 2019 Comments off

Ephemeris for Thursday, June 6th. Today the Sun will be up for 15 hours and 26 minutes, setting at 9:25, and it will rise tomorrow at 5:57. The Moon, 3 days past new, will set at 12:40 tomorrow morning.

Today is the 75th anniversary of the greatest battle of World War II was the invasion of Normandy on D-Day, a date governed by the position of the Moon. The full moon on June the 6th, 1944 gave light for the gliders and paratroopers to carry out their operations at midnight. Plus the high tides were near noon and midnight and the low tides near dawn. The idea was to hit the beach at low tide to enable the landing craft to operate without hitting the obstacles the Germans planted in the tidal zone. It was great for the landing craft, but the troops had a lot of open beach to cover to get to some sort of shelter. The best days for the invasion were the 5th, 6th and 7th of June. Bad weather on the 5th caused a one day postponement.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

05/16/2019 – Ephemeris – Looking back at the Ranger program: Getting really close up pictures of the Moon

May 16, 2019 Comments off

Ephemeris for Thursday, May 16th. Today the Sun will be up for 14 hours and 51 minutes, setting at 9:05, and it will rise tomorrow at 6:12. The Moon, 2 days before full, will set at 5:51 tomorrow morning.

The reconnaissance missions that had to be accomplished before the United Stated could land on the Moon in 1969 started with the Ranger program. The idea was to send a spacecraft to crash on the Moon taking and transmitting television pictures all the way down. In addition to the camera some Ranger spacecraft had a lunar capsule with a seismometer with a retro rocket to slow that package down and survive the landing. That feature never worked. Nine Rangers were launched. Only the last three were successful in returning images. Each returned thousands of images each returning detail down to 20 inches. One surprise, the rays we see from craters like Copernicus are actually chains of craterlets caused by ejecta from the impact.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Here’s a time lapse video of Ranger 9 hitting the crater Alphonsus. 17 minutes collapsed into 13 seconds:  https://www.youtube.com/watch?v=hpFifHgZyrg

05/14/2019 – Ephemeris – The Apollo 11 crew weren’t alone at the Moon

May 14, 2019 Comments off

Ephemeris for Tuesday, May 14th. Today the Sun will be up for 14 hours and 47 minutes, setting at 9:03, and it will rise tomorrow at 6:14. The Moon, 3 days past first quarter, will set at 4:54 tomorrow morning.

By the time Apollo 11 launched on July 16th, 1969 the Soviet union had its two launch failures of their massive lunar rocket the N-1 that year. In a last ditch attempt to scoop the United States, literally, the Soviet Union launched their Lunar 15 spacecraft that was to return a sample of the lunar surface material before Apollo 11 could return from the Moon with theirs. The Soviets launched Luna 15 on July 13th, and entered lunar orbit on the 17th. It descended to the lunar surface while Armstrong and Aldrin were still on the Moon. However communication was lost during descent and it crashed into the Sea of Crises several hundred miles northeast of where the Eagle had landed. The US was kept apprised of the Lunar 15 mission by the Soviets.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Luna-15

Luna-15 type vehicle the Soviets sent to the Moon to bring back surface samples. Credit NASA.