Many folks would like to see us back on the Moon and developing its resources.

Monday, October 10, 2005

Good day,
Larry Klaes posted the below two links.
The Lunar Constants PDF file link opens an HTML page where you can down load
an 82 page, 24.3 Mb, PDF file with all kinds of information about the Moon.
Thanks Larry Klaes. - LRK -

The second link Larry Klaes posted is also about the Moon and how the heat
of the Sun makes for seismic noisy Moon. One would hope at the poles this
would be less so if you are going to set up telescopes. Maybe in one of
those cold dark craters where there might be frozen water would be stable.
Just would limit your view angle if you went too deep. :-) - LRK -

On some of the Yahoo groups about the Apollo missions there has been recent
talks about launch angles and the need to make adjustments after the Trans
Lunar Injection (TLI) burn. Also why the ISS in its present orbit to make
access to it by Russia is not the right orbit for launching to the Moon.
One likes to take advantage of the Earth rotational speed to help you get
into orbit but you also have to take into account where your launch angle is
slinging you into space. You would like that first orbit around Earth to be
in the correct plane to place you in front of the Moon as the Moon and your
spacecraft arrive in the same proximity. The Earth is tilted, the Moon's
orbit is tilted, and matching everything up without having to make right
angle turns in space is just part of the planning. It is why you don't just
launch when you get through with your morning coffee.
- LRK -
Pioneer 10 passed the orbit of the Moon in 11 hours on its way to
upiter. - LRK -

Pioneer 10 was launched on 2 March 1972 on top of an Atlas/Centaur/TE364-4
launch vehicle. The launch marked the first use of the Atlas-Centaur as a
three-stage launch vehicle. The third stage was required to rocket Pioneer
10 to the speed of 51,810 kilometers per hour (32,400 mph) needed for the
flight to Jupiter. This made Pioneer the fastest manmade object to leave the
Earth, fast enough to pass the Moon in 11 hours and to cross the Mars orbit,
about 80 million kilometers (50 million miles) away, in just 12 weeks.

Lunar Prospector took 105 hours to get to the Moon. It was launched January
7, 1998 02:28:42.7 UTC with a launch azimuth of 97 deg E (29.2 deg
inclination) and a parking orbit of 87.7 x 102.7 nmi. Different months with
different launch windows gave different times of flight. You pick the wrong
day and time and you don't have enough fuel or you buy space on a different
launch vehicle. - LRK -
Lunar Prospector Mission Design & Trajectory Support.

Apollo 11 with 3 astronauts onboard took about 4 days. Touchdown on the
moon took place, as scheduled, on July 20, 102 hours, 47 minutes, and 11
seconds after launch from Cape Kennedy. (see link below - LRK -)

When you are tracking these launches into space you need to point and
antenna at the spacecraft and keep it pointing at the craft as the Earth
turns, the ocean tides flex the ground below you, the atmosphere bends the
radio signal much as a pond bends the light when trying to spear a fish.
The Earths rotation wobbles over time, the Sun may get into your eye and its
gravitational field bends your signal. The Solar Flare can ionize the upper
atmosphere which can bend some radio signals. - LRK -

If you read the 55 page, pdf file about the Pioneer Anomaly you will see
that many things have to been considered in tracking spacecraft that are out
of the Solar system. The Earth's rotation is slowing, the Moon is leaving
us ever so slowly, the tides flex the Earth. The Sun's gravitational pull
on the Moon wobbles the Moons orbit. What you see of the Moon is affected by
whether it is above you or below you on its slide around the Earth or
whether it is closer or further away. - LRK -
------------------------------------------------------- (55 page, 1.5 meg -
LRK - )
Journal-ref: Phys.Rev. D65 (2002) 082004
Our previous analyses of radio Doppler and ranging data from distant
spacecraft in the solar system indicated that an apparent anomalous
acceleration is acting on Pioneer 10 and 11, with a magnitude a_P ~ 8 x
10^{-8} cm/s^2, directed towards the Sun (anderson,moriond). Much effort has
been expended looking for possible systematic origins of the residuals, but
none has been found. A detailed investigation of effects both external to
and internal to the spacecraft, as well as those due to modeling and
computational techniques, is provided. We also discuss the methods,
theoretical models, and experimental techniques used to detect and study
small forces acting on interplanetary spacecraft. These include the methods
of radio Doppler data collection, data editing, and data reduction.
There is now further data for the Pioneer 10 orbit determination. The
extended Pioneer 10 data set spans 3 January 1987 to 22 July 1998. [For
Pioneer 11 the shorter span goes from 5 January 1987 to the time of loss of
coherent data on 1 October 1990.] With these data sets and more detailed
studies of all the systematics, we now give a result, of a_P = (8.74 +/-
1.33) x 10^{-8} cm/s^2. (Annual/diurnal variations on top of a_P, that leave
a_P unchanged, are also reported and discussed.)

F. Orbit determination procedure

Our orbit determination procedure first determines the spacecraft’s initial position and velocity in a data interval. For each data interval, we then estimate the magnitudes of the orientation maneuvers, if any. The analyses are modeled to include the effects of planetary perturbations, radiation pressure, the interplanetary media, general relativity, and bias and drift in the Doppler and range (if available). Planetary coordinates and solar system masses are obtained using JPL’s Export Planetary Ephemeris DE405, where DE stands for the Development Ephemeris. [Earlier in the study, DE200 was used. See Section VA.]
We include models of precession, nutation, sidereal rotation, polar motion, tidal effects, and tectonic plates drift. Model values of the tidal deceleration, nonuniformity of rotation, polar motion, Love numbers, and Chandler wobble are obtained observationally, by means of Lunar and Satellite Laser Ranging (LLR and SLR) techniques and VLBI. Previously they were combined into a common publication by either the International Earth Rotation Service (IERS) or by the United States Naval Observatory (USNO). Currently this information is provided by the ICRF. JPL’s Earth Orientation Parameters (EOP) is a major source contributor to the ICRF.

To display the date, time, and distance of lunar perigees and apogees for a given year, enter the year in the box below and press "Calculate". Depending on the speed of your computer, it may take a while for the results to appear in the text boxes. This page requires your browser to support JavaScript, and that JavaScript be enabled; all computation is done on your own computer so you can, if you wish, save this page in a file and use it even when not
connected to the Internet.

Earth's Eccentric Companion

The Moon's orbit around the Earth is elliptical, with a substantial eccentricity (as major Solar System bodies go) of 5.49%. In addition, the tidal effect of the Sun's gravitational field increases the eccentricity when the orbit's major axis is aligned with the Sun-Earth vector or, in
other words, the Moon is full or new.
The combined effects of orbital eccentricity and the Sun's tides result in a substantial difference in the apparent size and brightness of the Moon at perigee and apogee. Extreme values for perigee and apogee distance occur when perigee or apogee passage occurs close to new or full Moon, and long-term extremes are in the months near to Earth's perihelion passage
(closest approach to the Sun, when the Sun's tidal effects are strongest) in the first few days of January.
Now back to the Lunar Constants PDF file provided by JPL who is helping us
go back to the Moon.

Hope we don't lay everyone off. - LRK -
Taken from Inside KSC groups. - LRK -
The person who passed this information on to me has not told me how much is kosher to pass on. I will therefore keep things brief and vague.
The 300 laid off two weeks ago were contractors. The 300 to be laid off on monday are JPL employees. My contact states that the lay offs are due to the fact that JPL will not be participating in a significant way in the lunar exploration plan laid out by pres. Bush. It seems that NASA money is being shifted around as a result, and JPL will be getting the short end of
the stick for a while...

Looking up is getting harder with winds, rain, and earthquakes making the ground you stand on rather unstable.
Keeps tugging on my pocket book. :-(
- LRK -

Larry Kellogg
larry.kellogg at

Lunar Constants PDF file:

Reference: JPL Technical Document D-32296

The primary purpose of this document is to provide a single source for the constants and models to be used in the trajectory and navigation design of missions whose objective is to orbit or land on the Moon. A secondary objective is to provide the mission analyst with some basic background information about the Moon, its orbit, and the previous missions that have explored the Moon. As a result, this document contains more information than the typical constants and models document. Some of the data are required for mission studies while other data are simply provided for "educational purposes". This document provides only brief descriptions of the constants and models. The user should consult the references if more detailed information is desired.


This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
I would like to thank the following people for their key contributions to this document:
Alex Konopliv (Section 343), Myles Standish (Section 343), and Jim Williams (Section 335).
Their expert knowledge of the Moon, its orbit, and the proper formulation of algorithms necessary to perform precise calculations was absolutely invaluable. In addition, their thorough review of the document as a whole was also extremely helpful. I would also like to thank Mark Rosiek of the United States Geological Survey (USGS) for his help in understanding how to interpret and use the Clementine lunar topography data-files and for his general assistance with lunar maps.

Ralph Roncoli
Sunshine makes a noisy Moon:

A new technique for analyzing faint seismic noise recorded by instruments Apollo 17 astronauts left behind in 1972 may help geologists decipher the structure of the Moon, Mars, and other bodies.

October 2005 astro bytes
The rise and fall of the Amazon and a noisy Moon
October 4, 2005
Pulse of the Amazon

A team led by Michael Bevis at Ohio State University in Columbus has measured how seasonal river floods compress surrounding terrain. A global-positioning-satellite station in Manaus, Brazil, near the confluence of the Amazon and Rio Negro rivers, rises and falls each year by as much as 3 inches (75 millimeters).
This is the largest crustal oscillation observed to date on Earth — and more than twice that predicted for the region. The greatest compression occurs exactly when the Amazon floods. "This suggests that we are observing, for the first time, a purely elastic response to changes in the weight of a flowing river system," the team reports in the August 24, 2005, Geophysical
Research Letters. The area covered by the Amazon and its tributaries more than triples in the course of a year, expanding to as much as 135,000 square miles (350,0000 square kilometers). —
Francis Reddy

Sunshine makes a noisy Moon

A new technique for analyzing faint seismic noise recorded by instruments Apollo 17 astronauts left behind in 1972 may help geologists decipher the structure of the Moon, Mars, and other bodies.
A team led by Eric Larose of France's Laboratoire de Géophysique Interne et Tectonophysique in Grenoble matched up weak signals recorded by four vibration-detecting geophones placed in the Moon's Taurus-Littrow valley.
They studied data beamed to Earth from summer 1976 to April 1977, just a few months before NASA shut off all functional lunar stations.
The scientists, writing in the August 16, 2005, Geophysical Research Letters, noted a curious fluctuation in the noise. A closer look showed it repeated every 29.5 days — matching the Moon's phase cycle — and that signals were strongest during the day. The activity starts about 2 days after lunar sunrise and falls off fast after sunset.
As the lunar day begins, the Moon's surface temperature rises from –275° Fahrenheit (–170° Celsius) to 230° F (110° C). The team says lunar surface material, cracking in the heat, creates the signal. Apollo-era scientists explained the Moon's tiniest quakes the same way, calling them "thermal moonquakes."
Thanks for looking up with me.
- LRK -

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