PART 1: Take the Challenge!
PART 2: How to View a NASA TV Broadcast
PART 3: Global Surveyor Flight Status
PART 4: Pathfinder Mission Status
PART 5: Subscribing & Unsubscribing: How to do it!

Due to an error in how CQ#3 was transcribed last week, it has been
rewritten and reposted. Your kids have a second opportunity to
answer it.

CQ #3: DIFFERENCES AND SIMILARITIES -- CAN YOU NAME THEM?:
Discount (ignore, forget about...) one feature that makes Earth unique
among the planets (but maybe not the moons) of our solar system,
and Earth and Mars are almost identical in a certain aspect.

What do you have to take away from Earth?
In what way are Earth and Mars then alike?

Bonus question: Whatever do we mean when we say this feature may
make Earth unique compared to the planets...but maybe not "the
moons" of our solar system?

Send your answers to jwee@quest.arc.nasa.gov. They will be
accepted through next Wednesday, April 16.


CQ #4: GO TELL IT ON THE MOUNTAIN
Olympus Mons is the highest feature on Mars. What is its counterpart
on Earth? Be forewarned: it is not Mount Everest!

Bonus Question:
If you think about how astronomers measure the height of features
on Mars, you'll have a clue to help this question. What do we mean?

You are invited to send original student answers to:
jwee@mail.arc.nasa.gov. Please include the words CHALLENGE
QUESTION in the subject line of your email. The kids' names will be
listed online and token prizes will be given to those will the best
answers.

Answers are due within seven full days of Challenge Question
posting. (e.g. If a CQ is posted on April 11, answers are due by
midnight PST on April 18.)

A list of answers from all students who submitted them will be
posted on the Live From Mars Web site soon.

How to View a NASA TV Broadcast

Live From Mars programs are broadcast *live* via both NASA-TV and
PBS' main satellite, Telstar 402. "Cruising Between the Planets"
will air at 1-2 pm EST on Thursday, April 24.

You have two options for downlinking the program via satellite:
1) NASA-TV satellite coordinates on C-Band. NASA TV may preempt
scheduled programming for live agency events.

Effective March 15, 1997, the NASA TV satellite changed to:
- GE-2
- transponder 9C at 85 degrees West longitude
- vertical polarization
- frequency of 3880 Mhz and audio of 6.8 Mhz.

2): Satellite coordinates for Ku-Band PBS carriage:
- Telstar 402 R
- 7 Lower
- 89 degrees West
- frequency 11895 vertical
- 6.2 and 6.8 audio


Also, your local PBS station may be carrying the Live From Mars
programs live or via tape delay. Call your local PBS station and
inquire about their plans. Each PBS station (education coordinator)
receives LFM background information. If they are not aware of the
PTK programming and are interested in more information, they may
call the PTK Office at 973-656-9403. Our office can fax them
details if they are missing key information!

Educators without satellite dish access or lack local PBS feeds
should not give up! Call your local cable company and see if they can
help access the feed. Check with a local higher education agency;
many of these folks have satellite dishes and may be willing to tape
the program for you. How about a parent with a dish? Many PTK
participating educators have told inspiring stories of how they
creatively acquired our programming. PTK does make available
copies of the programs within one week of the live telecast for a
nominal charge. Contact Jan Wee for further details:
jwee@mail.arc.nasa.gov

GLOBAL SURVEYOR FLIGHT STATUS

[Editor's note: This status report was prepared by the Office of the
Flight Operations Manager, Mars Surveyor Operations Project, NASA
Jet Propulsion Laboratory.]

4 April, 1997

On Saturday, March 29, the flight team performed a several-hour
communications test to measure low-level interference between
Surveyor's ultra-stable-oscillator-generated X-band signal and the
Ka-band signal. Normally, the spacecraft utilizes the 25-watt, X-
band transmitter for communicating with the Earth. The main
differences between the two are that the 1-watt, Ka-band
transmitter is experimental and operates at a frequency near 32
GigaHertz versus 8 GigaHertz for X-band.

During last Saturday's test, the spacecraft simultaneously activated
both the X- and Ka-band signal sources. The test was designed to
determine the effect of the Ka-band signal on the purity of the X-
band signal as generated by the ultra-stable oscillator.
Understanding the performance of the oscillator under potential
interference conditions is important because this device functions
as an electronic clock that precisely controls the tone of Surveyor's
radio signal. Precision control of the signal's tone is important for
gathering data regarding the Martian atmosphere.

On Monday, March 31, the spacecraft passed through a major
milestone on its way to Mars. For the first time in the mission,
Surveyor was closer to Mars than to Earth. This equi-distant point
was approximately 57 million kilometers between the two planets.
The half-way point measured in terms of days to reach Mars will
occur on April 10.

After a mission-elapsed time of 148 days from launch, Surveyor is
61.05 million kilometers from the Earth, 53.20 million kilometers
from Mars, and is moving in an orbit around the Sun with a velocity
of 25.36 kilometers per second. This orbit will intercept Mars on
September 12, 1997. The spacecraft is currently executing the C6
command sequence, and all systems continue to be in an excellent
condition.

PATHFINDER MISSION STATUS

[Editor's note: This status report was prepared by the Office of the
Flight Operations Manager, Mars Pathfinder Mission, NASA Jet
Propulsion Laboratory.]

4 April 1997

The spacecraft remains in good health and is currently about 64
million kilometers from Earth. The most significant spacecraft
activity performed this week was to switch to a new convolutional
code, K=15, Rate 1/6, on our downlink. This code gives us a
significant increase in our downlink capability. Mars Pathfinder is
the first spacecraft to operationally use this code with the Deep
Space Network and we are very pleased with the results.

The project conducted a meeting to discuss flight software changes
for Entry, Descent and Landing and Surface phases of the mission.
These changes are to correct bugs found during testing performed
since launch. We expect to finalize these changes and prepare for
loading them onboard within the next two months.

SUBSCRIBING & UNSUBSCRIBING: HOW TO DO IT!

If this is your first message from the updates-lfm list, welcome!

To catch up on back issues, please visit the following Internet URL:
http://passporttoknowledge.com/lfm/updates
To subscribe to the updates-lfm mailing list (where this message
came from), send a message to:
   listmanager@passporttoknowledge.com
In the message body, write these words:
   subscribe updates-lfm

CONVERSELY...

To remove your name from the updates-lfm mailing list, send a
message to:
   listmanager@passporttoknowledge.com
In the message body, write these words:
   unsubscribe updates-lfm

If you have Web access, please visit our "continuous construction"
site at http://passporttoknowledge.com/lfm