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What rocks are used to radiometrically date a planetary surface?

admin — Sun, 06 Jun 2010 17:16:40 +0000

20) Which of the following type(s) of rock can always be used to reliably radiometrically date a planetary surface?
a) Metamorphic
b) Sedimentary
c) Igneous
d) All of them can be reliably used to radiometrically date a planetary surface.
e) (a) and (b) only
f) (a) and (c) only
g) (b) and (c) only

Only igneous rocks (c) can be accurately radiometrically dated to give an absolute age. Dating sedimentary rock will only date the age of the particle within the sedimentary rock (so it may have lithified last week, but it’s made of billion year old granite, so you’ll get an age of a billion years, which is wrong). Dating a metamorphic rock can be done, but you’re only dating its age of metamorphism. That may well be an interesting piece of information for geologists who already know something about the area, but it would be useless if you were dropped onto an unknown planet and asked to determine its age.

The correct answer is (c) igneous.

What affect does a Planetary Allignment have on the Earth?

admin — Thu, 27 May 2010 00:13:20 +0000

2012 Planetary Allignment – will it affect Earth’s magnetic field or Schuman Resonance?

1) There is no particular planetary alignment in 2012: http://www.fourmilab.ch/cgi-bin/Solar?date=1&utc=2012%2F12%2F21+11%3A12%3A00&jd=2476948.34564&img=-k0&sys=-Sf&eyes=0&imgsize=320&orb=-b0&lat=47%B0&ns=North&lon=7%B0&ew=East&hlat=90%B0&hns=North&hlon=0%B0&elements=
2) Planetary alignments have no measurable effect on Earth. If all the planets were to align perfectly with each one as close as possible to the Earth, their gravity would raise the ocean tides by just one twenty-fifth of one millimeter.
http://science.nasa.gov/headlines/y2000/ast30mar_1m.htm
3) Schumann Resonance depends on the speed of light and the Earth’s circumference. Since neither of these quantities is likely to change, Schumann Resonance won’t change either.
In short, if you read about anything at all unusual predicted for 2012, ignore it because it’s been made up by new-age loons and conspiracy wackos.

How do I know my planetary placement/what is planetary placement?

admin — Sun, 23 May 2010 19:16:45 +0000

I was born March 20, 1992 I am a Pisces but I am on the Pisces/Aries cusp. what is planetary placement and how do I find out mine?

http://astro.cafeastrology.com/cgi-bin/astro/natal
http://cafeastrology.com/articles/planetsinastrology.html
or
http://www.astro.com/

Two good sites to know about your planetary placements. Cusps aren’t really taken into account by astrologers, except when in critical degrees, I’ve heard. Your Sun sign is Pisces. There’s a Moon sign, Venus, Mars, Mercury, etc. Those sites should explain it all. Just navigate through them.

What ancient observations show that the all planetary orbits lie approximately in one plane? What observatio?

admin — Thu, 20 May 2010 19:43:32 +0000

What ancient observations show that the all planetary orbits lie approximately in one plane?

Anyone know what ancient observations I can use to answer this question? Thanks

The ancients noticed that the planets move among the so-called "fixed stars" in the
sky, and all the planets move through the same constellations as the years pass.
That is, they all follow the same, or nearly the same, path through the sky.
They called this band around the sky where the planets are seen the zodiac. All 5
of the planets they knew as well as the moon and sun stay in this narrow band and
don’t stray out of it. It includes all or parts of 13 constellations, the 12 classic ones
plus part of Ophiuchus, the serpent-holder, but for superstitious reasons they didn’t
want an unlucky number of constellations in their zodiac.
The facts that the planets all follow fixed predictable paths through the sky and all
the planets pass through the same parts of the sky, not different parts, indicate that
the planetary orbits lie in the same plane, or nearly so. With the exception of Pluto,
all the orbits only vary by a few degrees, and the ancients didn’t know about Pluto.
Hope this answers your question.

What careers are there in planetary science?

admin — Mon, 17 May 2010 06:22:08 +0000

I love astronomy an I was wondering what jobs are open to me if I pursue planetary science?

For astronomy I suggest you work up on your maths, physics, and astrophysics.
English is also good if you are not good at it, you will have to make reports.

There is not a lot of jobs to offer for astronomy though. About 150 openings per year.
Most work in colleges or universities.
Some work to do a lot of research at observatories or labs or be part of a space mission.
A small percent work in government labs because it is VERY hard to get accepted by the government.
My major is astronomy, but I will also be majoring in other areas because you have to be very good in physics and mathematics and whatever else.
I have chosen to enlist into the US Air Force to build up my major and possibly do some engineering.
If you go onto NASA’s website they have jobs to offer but I don’t know if those positions are available as of now.
They actually have a lot of job positions besides being an astronaut (meteorologist, scientist, engineers, etc.)
Don’t listen to those people who turn you down or anything like that. It’s because lots of people in my life think it won’t get me anywhere. Every time I mention NASA people always think I want to be an astronaut when they don’t know about the other possible careers.
Hope I helped!

What is the difference between a diffuse and a planetary nebula?

admin — Thu, 06 May 2010 16:26:38 +0000

How does each one form, and what dictates whether it will be planetary or diffuse?

How will that affect star formation?
Can stars form from planetary nebula?
What gives a diffuse nebula such a distorted shape?
What is the difference between a diffuse nebula and a supernova remnant?
Are stars able to form from supernova remnants?
Are stars able to form from planetary nebulae?

Idk about the planetary vs diffuse thing but stars can form from a supernova I’m pretty sure and I’m for sure they can form from planetary nebulae

How long will it take the Sun’s planetary nebula, expanding at a speed of 50 km/s, to reach the orbit of Neptu?

admin — Sun, 18 Apr 2010 22:40:32 +0000

How long will it take the Sun’s planetary nebula, expanding at a speed of 50 km/s, to reach the orbit of Neptune (in years)?

How long to reach the nearest star (in years)?

Time = distance / speed.

Travelling at 50 km/s it would take approximately 3.7 years to reach Neptune

Travelling at 50 km/s it would take approximately 25,177 years to reach Proxima Centauri (the nearest star to the Sun)

—

Please note: When the Sun turns into a planetary nebula it will expand much faster than 50 km/s, and it will not expand out to Neptune, let alone Proxima Centauri.

Planetary Systems Around Other Stars

admin — Sat, 17 Apr 2010 12:20:13 +0000

Guest lecturer Dr. Geoff Marcy gives a lecture entitled, “Planetary Systems Around other Stars,” for Professor Lynn Rothschild’s Astrobiology and Space Exploration course.

Stanford University:
http://www.stanford.edu/

Full Course Available on Stanford on iTunes U [iTunes Link]:
http://deimos3.apple.com/WebObjects/Core.woa/Browse/itunes.stanford.edu.1524698736.01524698739

Stanford University Channel on YouTube:
http://www.youtube.com/stanford

Duration : 1:26:28

[youtube -jc9XZ4-D0E]

Getting to know our planetary neighbours

admin — Wed, 14 Apr 2010 11:23:35 +0000

How well do we really know our Solar System? While we may be starting to unravel the secrets of Earth and its closest neighbours Mars and Venus, the ‘gas giants,’ like Jupiter and Saturn, that are much further afield remain shrouded in mystery. This edition of Space looks at the story of the forgotten planets.

Duration : 0:8:30

[youtube GgHXBL5ffw0]

A Hathor Planetary Message Through Tom Kenyon Pt1 – August 10, 2009

admin — Sun, 11 Apr 2010 14:07:32 +0000

Lies, Half-Truths and Manipulations – The Hathors
August 10, 2009
A Hathor Planetary Message Through Tom Kenyon

http://www.tomkenyon.com

Observations from Tom Kenyon:

“First of all let me say that the Hathors are, in no way,
telling any of us what to do. They are simply sharing what
they see in the current world situation.

Prophecies are strange animals. Their purpose is to alert us to possible future outcomes, but they are not written in
stone. I sometimes use the metaphor of a nearly flat tire to
describe what happens with prophecy.
If you are driving your car and someone brings to your
attention that you have very low tire pressure and are on the verge of a flat tire, they are giving you a prophecy. Now if you were to respond to this the way some persons respond to prophecy, you might say “Oh, my God, I am going to have a flat tire and there is nothing I can do about it.”
The truth is that you would then be limiting yourself to a
very narrow view of possibility. Another more resourceful
possibility would be to go get your freaking tire fixed (or
at the very least re-inflated). Then you would have changed the prophecy.
Prophecies are, by their nature, meant to be altered. And the power to change a prophecy (no matter how dire it may be) is through our ability to make choices.
But first of all, we have to know that we even have the
possibility to make choices…”