Name: Citra Kartika Devi
NPM/Class: 11611673 /4SA02
Lecturer: Defi Julianti
Subject: Pemb. B. Inggris
Berbantuan Komputer
Nasa's Orion 'Mars
ship' set for test flight
By Jonathan AmosScience
correspondent, BBC News, Cape Canaveral
A US space capsule that could help get humans
to Mars is due to make its maiden flight later.
Orion will be
launched on a Delta rocket out of Cape Canaveral in Florida on a short journey
above the Earth to test key technologies.
The conical
vessel is reminiscent of the Apollo command ships that took men to the Moon in
the 1960s and 1970s, but bigger and with cutting-edge systems.
Given that
this is a first outing, there will be no people aboard.
Nonetheless,
the US space agency describes the demonstration as a major event.
"This is
huge; Thursday is a giant day for us," said Nasa administrator Charlie
Bolden.
Lift-off is
scheduled to occur at 07:05 local time (12:05 GMT), depending on the weather
and the technical readiness of all involved.
Orion is being
developed alongside a powerful new rocket that will have its own debut in 2017
or 2018.
Together, they
will form the core capabilities needed to send humans beyond the International
Space Station to destinations such as the Red Planet.
For Thursday's flight, the Delta IV-Heavy rocket - currently the
beefiest launcher in the world - is being used as a stand-in.
It will send Orion twice around the globe, throwing the ship up to an
altitude of almost 6,000km (19,600ft).
This will set up a fast fall back to Earth, with a re-entry speed into
the atmosphere close to 30,000km/h (20,000mph) - near what would be expected of
a capsule coming back from the Moon.
It should give engineers the opportunity to check the performance of
Orion's critical heat shield, which is likely to experience temperatures in
excess of 2,000C (4,000F).
They will also watch how the parachutes deploy as they gently lower the
capsule into Pacific waters off Mexico's Baja California Peninsula.
Although Orion is a Nasa project, the
development has been contracted to Lockheed Martin, and the aerospace giant
will be running the show on Thursday.
But the US
space agency will be there in the background, keen to see that the LM designs
meet their specifications.
A good example
is the radiation protection built into the capsule. Radiation will be one of
the major hazards faced on voyages into deep space, and Orion's systems must
cope with the challenge.
"We're
going to be flying through parts of the Van Allen radiation belts, since we're
15 times higher than the space station," explained Mark Geyer, Nasa's
Orion programme manager.
"The ISS
would not have to deal with radiation but we will, and so will every vehicle
that goes to the Moon. That's a big issue for the computers. These processors
that are now so small - they're great for speed but they're more susceptible to
radiation. That's something we have to design for and see how it all
behaves."
Thursday's
mission is but one small step in a very long development programme. Unable to
call upon the financial resources of the Apollo era, Nasa is instead having to
take a patient path.
Even if today
it had a fully functioning Orion, with its dedicated rocket, Nasa would not be
able to mount a mission to another planetary body because the technology to
carry out surfaces operations has not been produced yet.
This worries
observers like space historian John Logsdon, who doubts the policy as currently
envisaged in sustainable.
He told the
BBC: "The first launch with a crew aboard is 2020/21, and then nothing
very firmly is defined after that, although of course Nasa has plans. That's
too slow-paced to keep the launch teams sharp, to keep everyone engaged. It's
driven by the lack of money, not the technical barriers."
One solution
is to pull in international partners. Europe, for instance, is going to make
the "back end" for all future Orion capsules.
This service
module is principally the propulsion unit that drives Orion through space. Prof
Logsdon wonders if additional partners might want to pick up some of the other
technologies needed to help speed the exploration path.
1. Lift-off is
scheduled to occur at 07:05 local time (12:05 GMT), depending on the weather
and the technical readiness of all involved.
The word depending in this
sentence is included to present participle because it is formed by the verb depend and is ended
by the suffix -ing. The function of the present participle is as an
adjective because it modifies the noun.
2. Orion is being
developed alongside a powerful new rocket that will have its own debut in 2017
or 2018.
The word being in the
sentence above functions as present participle since it is formed by the verb be and is ended
by the suffix -ing. It is considered to main verb, with the passive form
of the –ing form is usually made by "being + past participle such in this
sentence.
3. "We're
going to be flying through parts of the Van Allen radiation belts, since we're
15 times higher than the space station,"
The word going in
sentence above can be concluded into a present participle because it comes from
the verb go and the
suffix -ing. The function
of the present participle going in the
sentence above is as a verb because it occurs in the Present Progressive Tense.
4. Nasa is
instead of having to take a patient path.
The word having in the
sentence above is included to gerund because it is formed by the verb have that is ended
by the suffix -ing and it
functions as a noun. The position of having is as object of preposition
since it is preceded by the preposition instead of.
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