Problems with Cassini?

Anyone hear that the mission is not going well and Cassini is way off
course?

Um... No.

Last update from the Cassini team reported everything is going well.

And, by the way, there isn't much of a way for Cassini to be 'way off
course.'

It isn't a ship, or a car, or a truck. It's a spacecraft, in the vacuum of
space.

There isn't any wind, or water or currents to act on Cassini's motion, just
the constants of the gravitational fields of Saturn (and its moons to a much
smaller extent) and the distance of Cassini to those bodies. (yes, yes, the
Sun is also a factor, as well as the other planets, but the amount of
gravitational attraction is miniscule)

Cassini fired it's rocket to slow itself just enough that it would not
escape Saturn's gravity back on July 1st (or June 31st depending on your
timezone). Thanks to a little thing called the Doppler shift (1) Cassini
started and ended the 'burn' with almost exactly the expected velocity and
direction.

Cassini won't be using that rocket for a long while now. The only other
propulsion on Cassini are the cold gas jets used to turn the spacecraft to
point where it needs to point.

What did you hear?

Jeffrey Cornish



(1) radiation emitted by objects (like radio waves from Cassini's radio
transmitter) have their frequency stretched when moving away from an
observer and compressed when approaching. You've heard this when an
emergency vehicle has passed you with it's sirens on. It's also known as
redshift/blueshift for electromagnetic radiation.
"Marshall Karp" wrote in message
...
Anyone hear that the mission is not going well and Cassini is way off
course?

"Jeffrey Cornish" wrote in message
...
Thanks to a little thing called the Doppler shift (1) Cassini
started and ended the 'burn' with almost exactly the expected velocity and
direction.

Okay, correction he

Thanks to a little thing called the Doppler shift (1) _The Cassini team were
able to confirm that_ Cassini started and ended the 'burn' with almost
exactly the expected velocity and direction.

"Marshall Karp" wrote in news:mPOdnd3oi_cEF2PdRVn-
:

Anyone hear that the mission is not going well and Cassini is way off
course?



No, exactly the opposite. What's your source of misinformation?

--Damon

"Damon Hill" wrote in message
34...
"Marshall Karp" wrote in news:mPOdnd3oi_cEF2PdRVn-
:

Anyone hear that the mission is not going well and Cassini is way off
course?



No, exactly the opposite. What's your source of misinformation?

There was an article on space.com for the Palm by Leonard David about earth
weather systems causing some communications problems. I can't find the
article on space.com, but maybe the OP misunderstood this article?

BV.

"Benign Vanilla" wrote in
:


"Damon Hill" wrote in message
34...
"Marshall Karp" wrote in
news:mPOdnd3oi_cEF2PdRVn- :

Anyone hear that the mission is not going well and Cassini is way
off course?



No, exactly the opposite. What's your source of misinformation?

There was an article on space.com for the Palm by Leonard David about
earth weather systems causing some communications problems. I can't
find the article on space.com, but maybe the OP misunderstood this
article?

Ah, probably confused by the solar occultation; for a few days
communications was minimal because Saturn was so close to the Sun
from Earth's perspective.

--Damon

Damon Hill wrote:


There was an article on space.com for the Palm by Leonard David about
earth weather systems causing some communications problems. I can't
find the article on space.com, but maybe the OP misunderstood this
article?



Ah, probably confused by the solar occultation; for a few days
communications was minimal because Saturn was so close to the Sun
from Earth's perspective.

--Damon



There was some concern on orbit insertion day that weather conditions at
one of NASA's Deep Space Tracking dishes in Australia (Canberra I
believe) might be too windy to allow them to deploy the antenna.
However the weather improved enough to allow them to use it. As the
previous poster also mentioned Saturn with Cassini, as seen from Earth
passed behind the Sun making data transmission quite difficult.

From the weekly sastus reports:

"Solar Conjunction occurs when the Sun is between the spacecraft and
Earth.
This year it will last from July 5 through July 11, and is a time of
reduced
commanding and downlink capability. During this period the project will
uplink a command file consisting of 10 no-op commands sent every 5
minutes,
10 to 20 times daily. The purpose of the test is to accumulate
statistics
for uplink reliability at decreased separation angles."

In message , Damon Hill
writes
"Marshall Karp" wrote in news:mPOdnd3oi_cEF2PdRVn-
:

Anyone hear that the mission is not going well and Cassini is way off
course?



No, exactly the opposite. What's your source of misinformation?

--Damon

Http://www.coasttocoastam.com, according to his other post with the
same subject line. Richard Hoagland quoting an un-named source.
This might be connected to a new page on the enlightened one's own site
at http://www.enterprisemission.com/, titled "Is NASA Sending the
Cassini Mission to its Doom ?!" but it's so badly laid out I can't be
bothered to look at it.

JRS: In article , dated Wed, 21
Jul 2004 09:13:40, seen in news:sci.space.shuttle, Jeffrey Cornish
posted :

Cassini fired it's rocket to slow itself just enough that it would not
escape Saturn's gravity back on July 1st (or June 31st depending on your
timezone).

Which time zones have 31 days in June?

--
© John Stockton, Surrey, UK. Turnpike v4.00 MIME. ©
Web URL:http://www.merlyn.demon.co.uk/ - w. FAQish topics, links, acronyms
PAS EXE etc : URL:http://www.merlyn.demon.co.uk/programs/ - see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.

In message , Dr John Stockton
writes
JRS: In article , dated Wed, 21
Jul 2004 09:13:40, seen in news:sci.space.shuttle, Jeffrey Cornish
posted :

Cassini fired it's rocket to slow itself just enough that it would not
escape Saturn's gravity back on July 1st (or June 31st depending on your
timezone).

Which time zones have 31 days in June?


Double Summer Time in Len Deighton's "Bomber"?