First Man-made item on the Moon...

[peteshimmon]

I have beem doing a little research on Luna 1
and Luna 2. It was the fate of the carrier
rockets that I was curious about. Wikipedia
and another site state the Luna 2 rocket was
30 minutes behind the probe. I did a naive
calculation based on the Moon being a moving
target and found it is about a quarter of a
degree further along its orbit and the rocket
should therefore miss. How the gravitational
field of the Moon upsets this conclusion I am
not sure.

What was very interesting was the stories of
the Hungarian astronomers who observed the
apparent dust cloud of Luna 2 at the time
of impact. It seems a true observation with
more than one observer.

But 30 minutes seems a long separation between
the probe and rocket if the probe was spring
separated. Do they mean 30 seconds? If so then
the impact of the rocket was much more likely
to be seen.

But if it was 30 minutes and the Luna 1 probe
and rocket had the same flight profile then,
depending on which side of the Moon it passed
there seems a possibility that its carrier
rocket was the first man-made item to hit
the Moon. This is a very wild speculation
but it seems justified.

[peteshimmon]

I come back to this subject after digging out
some ancient volumes which mention the event.

Firstly two British astronomers observing the
expected impact area on the Moon that September
evening, Moore and Wilkins, reported seeing a
faint flash at the exact time the signals
stopped. Now with the information that the
probe Luna 2 was a bit of a warhead, this
looks very credible. A sphere was included
that had stainless steel pennants fashioned
on it. And some explosive in the sphere. At
impact, an explosion was hoped to blow some
pennants upward preserving their message.
So a flash looks very likely. If the Luna 1
had the same contents then care must be
taken should it ever be recovered

Secondly, if the Hungarian observers saw
the dust cloud of the carrier rocket a
few seconds later then there must be two
fresh craters near each other one being
a bit smaller. It is a good project for
the LRO images being analysed.

[JustAFriend]

Certainly hope that someone tracks down and marks all the crash sites for future posterity.
We have to know what places to enshrine and which ones to go trophy hunting at...

[peteshimmon]

This thing about the carrier rocket being 30
minutes behind the probe has been bothering
me. I have read it on a number of websites
now but it does ring true, people are just
repeating a wrong assumption I think. A BIS
publication from 1963 has a different story,
A Handbook of Astronautics has a table which
gives the same time for probe and rocket.

Lets say a spring mechanism separates the
probe and rocket at 5 metres a second. Thats
300 metres a minute. Thats 18 Kilometres an
hour. Thats 612 Kilometers over a flightime
of 34 hours. At the terminal speed onto the
Moon, that would be a few seconds behind.

So unless I am missing something fundamental
there is duff gen out there.

[NEOWatcher]

So unless I am missing something fundamental
there is duff gen out there.

I have no clue how to determine this (or even explain it well). The moon is moving away (~90 degrees from the trajectory) then the first item to get there will be closer, while the second item would be further from the moon. Therefore, the second item will take a longer arc as it heads in for an impact.

[peteshimmon]

Well I did say in my opening post that a
moving Moon might cause a miss with a
30 minute gap between probe and rocket.
I should finish my crude maths, a
terminal velocity at the Moons surface
of 5000 Kilometres an hour would
indicate a 10 minute delay, not seconds.
But it was a fast trajectory to the
Moon and a separation of 5 metres a
second may be generous considering the
masses of the two items.

No, I need to be convinced this 30
minutes gap is right.

Its interesting to note that behind
all notable spaceprobes was a carrier
rocket, lonely, unloved, forgotten!
There are details I want to know
about, especially separation methods.

[Ara Pacis]

No, the first item was a manhole-cover launched during a nuke test.

[Jeff Root]

I wonder when that figure of "30 minutes" applied. The Wikipedia
page on Luna 1 says that "A malfunction in the ground-based control
system caused an error in the rocket's burntime, and the spacecraft
missed the target and flew by the Moon at a distance of 5,900 km
at the closest point." That *might* be the moment of the 30-minute
separation.

I also wonder on which side of the Moon Luna 1 passed. Probably
either the east or the west.

-- Jeff, in Minneapolis