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

May 16, 2019 Leave a comment

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.

05/13/2019 – Ephemeris – The Moon Rockets

May 13, 2019 Comments off

Ephemeris for Monday, May 13th. Today the Sun will be up for 14 hours and 44 minutes, setting at 9:01, and it will rise tomorrow at 6:15. The Moon, 2 days past first quarter, will set at 4:26 tomorrow morning.

In the race to the Moon in the 1960s we never really knew what the Soviet Union was doing, or of how far they progressed. We knew that we seemed to be behind because we would get glimpses of their progress when they pulled off some first, some long duration record, or the first woman in space. We never heard of their failures until after the Soviet Union fell in 1991. Their answer to the Saturn V rocket was the N-1, the first test of which was several months before Apollo 11 was launched. In all four N-1 launch attempts were made, none successful. However their counterpart to the Apollo Command and Service Modules still lives after 5 decades, it’s call the Soyuz, used to carry cosmonauts and astronauts to the International Space Station.

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

Addendum

Comparison between The United States Saturn V and the Soviet N-1. Credit: Griffith Observer, the magazine of Griffith Observatory.

N-1

Base of the N-1 and its 36 rocket engines. The N-1 is assembled horizontally while the Saturn V was assembled vertically.

 

05/09/2019 – Ephemeris – The USA: Step by step to the Moon

May 9, 2019 Comments off

Ephemeris for Thursday, May 9th. Today the Sun will be up for 14 hours and 35 minutes, setting at 8:57, and it will rise tomorrow at 6:20. The Moon, 2 days before first quarter, will set at 1:54 tomorrow morning.

The Apollo 11 manned landing on the Moon 50 years ago was the culmination of a series of incremental steps. The Mercury program was in progress when President Kennedy announce the goal to land on the Moon. Following that was Gemini a two man capsule to test long duration flight, rendezvous and docking of two spacecraft, and EVA’s or spacewalks. There was the Ranger program attempted to photograph the Moon close up by sending probes to crash into the Moon. The Lunar Orbiter program to map the entire Moon, the Surveyor program to soft land on the Moon and test its surface. All this leading up to the three man Apollo program to test out the strategy and equipment and to land humans on the Moon.

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

Addendum

Project Mercury

Project Mercury astronauts and a model of the Mercury-Atlas rocket and capsule. Left to right: Grissom, Shepard, Carpenter, Schirra, Slayton, Glenn and Cooper, in 1962. Click on the image to enlarge. Credit NASA.

Project Gemini

Project Gemini: Left Ed White during the US first space walk during Gemini 4 in June of 1965. Right The rendezvous of Gemini 6 & 7 in December of 1965. Click on the image to enlarge. Credit NASA.

Ranger Program

Left: The Ranger spacecraft. Right: The floor of the crater Alphonsus from Ranger 9. Only the last 3 spacecraft were successful. They transmitted images all the way down as they crashed into the Moon. Click on the image to enlarge. Credit NASA.

Lunar Orbiter program

In the most unheralded of the lunar programs the 5 successful Lunar Orbiter satellites photographed 99% of the Moon. from 1966 to 1967. The Moon was photographed on film in strips, developed and the images scanned and transmitted back to Earth. Right: The oblique view of the crater Copernicus was dubbed at the time “The Picture of the Century”. Click on the image to enlarge. Credit NASA.

Surveyor program

Surveyor 3, visited by astronaut Pete Conrad during the Apollo 12 mission. Click on the image to enlarge. Credit: NASA / Alan Bean.

 

05/07/2019 – Ephemeris – We’re starting to look at the race to the Moon that culminated 50 years ago

May 7, 2019 Comments off

Ephemeris for Tuesday, May 7th. Today the Sun will be up for 14 hours and 30 minutes, setting at 8:54, and it will rise tomorrow at 6:23. The Moon, 3 days past new, will set at 11:58 this evening.

As we look at the Moon near the planet Mars tonight, we recall that fifty years ago today the United States was one week from launching Apollo 10, the penultimate lunar mission to test out the Lunar Module shortened to LM pronounced “Lem” in the vicinity of the Moon. President Kennedy announced the goal in 1961 to send a man to the Moon and return him safely by the end of the decade. This required a lot of learning steps and in the end a huge rocket, the Saturn V. That rocket’s chief designer was Wernher von Braun an ex-Nazi officer who designed the German V-2 during World War II. His counterpart on the Soviet side was Sergei Korolev, though we didn’t know his name until after he died in 1966.  His death hampered the development of the Soviet’s N-1 moon rocket.

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

Addendum

Wernher von Braun

Wernher von Braun around 1960. Image is in the public domain.

Sergei Korolev

Sergei Korolev, undated image published after his death. Image is in the public domain.

A fascinating look of the Soviet side of the moon race can be found here: https://www.nasa.gov/connect/ebooks/rockets_people_vol4_detail.html.  The ebook Rockets and People Volume IV, The Moon Race by Korolev’s deputy Boris Chertok.  It’s available in epub, mobi and pdf formats.  Volume 3 covers from 1961 to 1967.  There are links to all the other volumes from that page.

04/16/2019 – Ephemeris – Last week was quite a week in astronomy and space

April 16, 2019 Comments off

Ephemeris for Tuesday, April 16th. Today the Sun will be up for 13 hours and 31 minutes, setting at 8:28, and it will rise tomorrow at 6:55. The Moon, 3 days before full, will set at 6:23 tomorrow morning.

Last week was quite a week in astronomy and space. Wednesday was the announcement that the Event Horizon Telescope team had actually imaged the supermassive black hole in the galaxy M87, using eight sub-millimeter radio telescopes observing from five continents simultaneously. We’ll have to wait a bit to get an image of the Milky Way’s supermassive black hole. Later that Day SpaceX launched their Falcon Heavy rocket to loft an Arab communications satellite into orbit. The three boosters landed safely. Thursday the Israeli privately financed Beresheet lunar lander almost landed safely on the Moon. Unfortunately its rocket engines failed during its landing attempt. They will build another and try again.

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

Addendum

Black hole in M87

The first image of the black hole in M87. Credit Event Horizon Telescope.

M87 Jet

A 5,000 light year long jet from the black hole M87* that’s actually aimed mostly toward us. So the accretion disk in the black hole image is like a halo around the event horizon seen from near the pole of rotation. Credit: NASA/The Hubble Heritage Team (STScI/AURA).

Falcon Heavy launch

Falcon Heavy leaves the pad. April 10, 2019. Credit SpaceX.

A selfie image of part of the Beresheet lander moments before contact was lost from the Beresheet spacecraft during its descent to the Moon. Credit: SpaceIL/Israel Aerospace Industries.

03/08/2019 – Ephemeris – International Women’s Day

March 8, 2019 Comments off

Ephemeris for International Women’s Day, Friday, March 8th. Today the Sun will be up for 11 hours and 31 minutes, setting at 6:39, and it will rise tomorrow at 7:06. The Moon, 2 days past new, will set at 8:43 this evening.

On this International Women’s Day let’s take a look in my favorite fields of astronomy and space. There’s Hypatia of Alexandria who was murdered by an ignorant mob in 415 AD, Caroline Herschel sister to William Herschel and among other things discovered 8 comets, Maria Mitchell, whose comet discovery rocketed her to fame in the United States in the 1800s, Annie Jump Cannon, who classified stars, Henrietta Leavitt who found how to find distances to far away galaxies, and Vera Rubin who helped discover dark matter. In space there’s Sally Ride, Mae Jamison, and Peggy Whitson, who holds the American space flight time, and EVA time records regardless of gender. And that’s just scratching the surface.

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

Addendum

Ten female astronomers everyone should know:  https://www.mnn.com/leaderboard/stories/10-female-astronomers-everyone-should-know.

My favorite astronomer on Twitter is astrophysicist Dr. Katherine J Mack @AstroKatie.