Point Arguello - a little history of PALC2-4
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There are two separate but physically adjacent spaceports in the Cape
Canaveral vicinity: Cape Canaveral Space Force Station and the NASA John
F. Kennedy Space Center. Although they are often conflated, they are
owned and operated separately (by Space Force and NASA).

Similarly, from 1959 to 1964 there were two separate, adjacent
spaceports on the California coast north of Santa Barbara near Lompoc:
Vandenberg Air Force Base and the Naval Missile Facility Point Arguello
(NMFPA).

The first space launch from Point Arguello was a Nike-Asp sounding rocket in Jul 1959
from Launch Complex A; the first orbital attempt was the 1960 Oct 11 launch
of SAMOS 1 on an Atlas Agena A from Launch Complex 1, Pad 1.

Point Arguello's Launch Complex 2, Pad 4 was not used for a launch
until August 1964, by which time NMFPA had been transferred to the Air Force
and become the South Base section of Vandenberg AFB - the pad was then called
Vandenberg AFB PALC2-4 (Point Arguello Launch Complex 2, Pad 4).

Because NMFPA was once a separate spaceport, I still track its pads
separately as `South Vandenberg' with site code VS in my launch database
(versus site code V for pads on the North Base).

In 1966 the Vandenberg and Point Arguello orbital pads were renamed
and PALC2-4 became Space Launch Complex 4-East (SLC-4E). It continued
launching Atlas Agena rockets with GAMBIT spysats until 1967; from 1971
to 2005 it was the home for Titan IIID and later Titan 34D and Titan 4.

After lying silent for eight years, in 2013 SLC-4E became the
West Coast launch site for SpaceX's Falcon 9. So far there have
been 17 Falcon 9 launches from the pad.

DART
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At 0621:02 UTC Nov 24, a Falcon 9 launched from SLC-4E at Vandenberg
Space Force Base with the DART (Double Asteroid Redirection Test)
spacecraft, sending it to solar orbit. Deep space launches are rare from
Vandenberg; the first was the Clementine probe, launched on a Titan II
from SLC-4W in 1994. 

Four Atlas V launches from SLC-3E in the 2009-2014 period deployed primary
payloads in Earth orbit but then boosted their Centaur upper
stages to solar orbit for disposal. Most recently, another
Atlas V took off from SLC-3E in 2018 carrying the Mars Insight probe.

The launch was the first deep space launch from
Space Launch Complex 4-East. The Falcon 9 headed south
from Vandenberg to a 230 x 300 km x 64.7 deg parking orbit.
After a short coast, the second stage reignited
over the Antarctic and boosted DART to a 263 x -135000 km x 64.7 deg
escape hyperbola. DART and the second stage will
depart the Earth-Sun Hill Sphere on Nov 30 at about 0700 UTC,
entering a 0.938 x 1.069 AU x 3.8 deg heliocentric orbit
on course for the (65803) Didymos system.

(65803) Didymos is a 780-metre-diameter asteroid orbiting
the Sun in a 1.01 x 1.64 AU x 3.4 deg orbit.
The half-gigatonne asteroid has a moon, the 163-metre-diameter Dimorphos
which has a mass of around a million tonnes and orbits Didymos at a 
center-to-center distance of only 1.2 km.

Didymos then shuttles between the orbit of Mars and the orbit of
Earth every 2.1 years. But usually when it comes close to Earth orbit,
Earth itself is at some other part of that orbit. Not this time:
Didymos is currently heading inward from aphelion and in Oct 2022
it will reach perihelion passing only about 11 million kilometers
from Earth!  OK, I know that sounds like a lot, but right now
it's 113 million km away.

Taking advantage of this close pass, NASA's DART
mission will go round the Sun in an orbit just a little bit different
from Earth's and reach Didymos just as it passes by Earth.
DART will reach the Didymos system in Oct 2022 and smash into Dimorphos.
The impact is expected to change the orbital period of Dimorphos around
Didymos by of order ten minutes, something that can be accurately
measured, allowing scientists to determine how efficiently the collision
imparts momentum to the target rock. This information will be crucial in
designing missions that could divert a possible future Earth-impacting
asteroid.

The DART mission is led by JHU's Applied Physics Laboratory (APL)
and is managed by NASA MSFC and the
NASA Planetary Defense Coordination Office. 
DART has a mass of 500 kg dry. It has two propulsion systems:
a set of twelve Aerojet Rockedtyne MR-103G thrusters
with a thrust of 1N each, fed by 50 kg of hydrazine; and the
7.4 kW NEXT-C ion engine with a thrust of 25 to 235 mN, fed
by 60 kg of Xe and powered by two ROSA roll-out solar arrays.
The main DART spacecraft, built by APL, is 1.2 x 1.3m in size
and the deployed ROSA arrays span 19 metres.
DART has one main instrument, the DRACO (Didymos Reconnaissance &
Asteroid Camera for OpNav) imaging camera. 10 days before the Didymos
encounter it will eject a 6U cubesat, LICIACube. The 14 kg LICIACube is
built by Argotec for the Italian space agency ASI; it carries two
cameras to image the impact.