3, 2, 1…liftoff! The science of launching rockets from Australia



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Aircraft and missiles on display at Woomera, South Australia. Will we launch more rockets from here in the future?
from www.shutterstock.com

Ingo Jahn, The University of Queensland

Australia’s space agency will officially commence operations on July 1 2018.

As inaugural agency head Megan Clarke surveys our national capability in space, many states are putting forward strong cases regarding their existing relationships, human resources and infrastructure.

But from where should Australia launch rockets? Woomera in South Australia launched its first rocket in 1967, but in reality Australia could support multiple launch sites. And the closer to the equator, typically the better.

Let’s look at why.




Read more:
No launch from Australia: something missing from our plans for the new space race


Launching the payload

The first step in a space venture is to launch the payload (typically a satellite) and get it to stay in a suitable orbit without falling back to earth.

To achieve this, first the rocket must lift itself and the payload from the launch pad, through the lower levels of the atmosphere to altitudes greater than 100 km. This is achieved using a near vertical trajectory.

Once outside the atmosphere, the climb angle is reduced and the rocket starts to accelerate to reach its orbital velocity. It must travel at more than 7.8km/s (approx 28000 km/h) to stay in Low-Earth Orbit (LEO). LEOs are orbits with an altitude of less than 2000km, and are used by the majority of small satellites.

The majority of the rocket fuel is used in this acceleration phase. The high final velocity is required to ensure the released payload stays in orbit.

However, by appropriate selection of launch site and launch direction, the required velocity to achieve LEO can be reduced.

The earth rotates one revolution per day in the westward direction, which results in a surface velocity of 0.46km/s (approx 1670 km/hr) at the equator. As you move north or south from the equator, this surface velocity decreases.

So, in the ideal case, launching westwards from the equator, the velocity to stay in LEO is reduced from 7.8km/s to approximately 7.3km/s.

As fuel required to attain these speeds is proportional to velocity squared, this is a substantial saving.




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Different launches for different orbits

This speed advantage is most important for spacecraft leaving earth and satellites going to geostationary orbit (a high earth orbit, where they rotate with earth and remain exactly above a fixed point on the ground). By launching from the equator in a purely westward direction they can fully utilise this speed advantage.

However, for small satellites aiming for LEO this has limited value. They would circle above the equator and could only view (or be visible from) a strip several hundreds of kilometres wide.

Instead most LEO launches are slightly to the north or south of the equator, so that the resulting orbit is inclined relative to the earth equatorial plane. From these orbits, after multiple passes, most of the earth (excluding the north and south pole) is visible.

A good example of such an orbit is the International Space Station, which can be tracked at ISS tracker.

International Space Station astronaut Ricky Arnold doing a spacewalk in June 2018.
NASA, CC BY

The exception to this are satellites in what are called sun synchronous and polar orbits, flying almost directly over the north and south pole. These require launches in the north or south direction and cannot utilise the speed advantage.




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Blue skies, no wind

The biggest motivator for building launch sites close to the equator is the the speed advantage and associated fuel savings mentioned above. Reductions in fuel mass allow increases in allowable payload mass.

This is reflected by the major well established spaceports: Cape Canaveral in Florida (USA), Baikonur Cosmodrome in Kazakhstan (Russia), Kourou in French Guinea (Europe), and Jiuqan (China) all of which are located in the vicinity of the equator.

Looking ahead, there will be significant demand for future launch capacity to LEO either on inclined or sun synchronous orbits, as they are easy to reach and well suited for observation and communication satellites.

Secondary considerations for choosing launch sites are weather and climate related. Obviously blue sky days with little wind are desirable for launching, but – as demonstrated by Cape Canaveral in Florida – it is possible to operate a space-port in a region regularly visited by hurricanes. Nevertheless NASA cites weather as one of the main causes for launch delays.

Finally, it is desirable for launch sites to be close to towns and cities so that people have somewhere to live, and so that launch sites can contribute to the local community.




Read more:
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Launching from Australia

Australia has a rich heritage in space related innovation, research, and collaboration, dating back to the NASA Mercury and Gemini programs.

Today there are several home-grown start-ups developing launch capabilities for access to space, such as Hypersonix and Gilmour Space Technologies (plus Rocketlab in New Zealand), all specifically targeting small satellite launches.

An evolution from this would be an Australian space port, which would further spur on these developments and help grow Australia’s space industry.

So far the majority of rocket launches in Australia have been conducted at the Woomera Prohibited Area, located in South Australia. An advantage of Woomera is that trajectories initially run over land. This allows easier communications with the rocket or flight experiment, making it ideal for rocket development. But this isn’t essential in space launches.

Being a large country, Australia can accommodate multiple launch sites. Equatorial Launch Australia (ELA) recently announced that they have secured land to start construction of the Arnhem Space Centre in the Northern Territory in 2018.

Similarly Australian Space Launch (ASL) is exploring locations in the Bowen region, North Queensland and Southern Launch have started site selection along the south coast.

Space launches from Australia can be expected in the not so distance future.
Having a national launch capability will significantly boost the growing space and satellite industry.


The Conversation


Read more:
Five steps Australia can take to build an effective space agency


Ingo Jahn, Senior Lecturer, The University of Queensland

This article was originally published on The Conversation. Read the original article.

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Budget 2018: when scientists make their case effectively, politicians listen


Alan Finkel, Office of the Chief Scientist

Budget 2018 confirms that the case for funding science is being heard in Canberra.

Science and research are integrated in the national objectives laid down in the treasurer’s speech: to create jobs, boost health and improve the liveability of communities.

Many of the measures appear to have origins in proposals advanced by the science community.




Read more:
Infographic: Budget 2018 at a glance


Lessons from Budget 2018

What lessons can we take from this year’s outcome? After two years in Canberra, I haven’t discovered a magic key to the Federal coffers. But here are my general observations.

Intrinsic value is not sufficient

We can’t assume that the broad public support for science will translate into support for specific proposals unless we do the work to explain the benefits, including more jobs and better health.

Being intrinsically valuable is not sufficient. Clarity about what we can deliver is essential when science is competing with spending proposals with obvious and immediate benefits – like more hospital beds.




Read more:
Science isn’t broken, but we can do better: here’s how


Politicians need help

It helps to remember that most politicians aren’t experts in science policy. I’ve wrestled for years with the term “national research infrastructure”. People I talk to outside the research sector simply don’t understand it. A small change to saying “national research facilities” turns the lights on.

Show outcomes

It’s important for politicians to see the outcomes of public investment. They see the dollar figures in the budget papers but they don’t necessarily connect the research breakthroughs they read about in the newspapers years later to the programs that made them possible. It is important to help local members, irrespective of their party, recognise the impact of previously funded programs working for Australians.

Review and communicate

Take stock of progress and give credit to what has been achieved to date before heading back into the arena for the next round. As custodians of public funds, researchers should be proud to share their achievements with the taxpayers who ultimately make them possible.




Read more:
Science Meets Parliament doesn’t let the rest of us off the hook


We’re all in this

Finally, I’ve always found politicians to be far more receptive to funding proposals when they see commitment from other quarters. It’s not just the Commonwealth that needs to step up. It’s business. It’s state and territory governments. It’s philanthropists.

If we reach out widely, we can strengthen our advocacy with new allies, and at the same time, help government to focus on the things that only government can do.

Below I highlight some key areas funded through Budget 2018.

Key science and technology items in Budget 2018, from the Australian Academy of Science.

National facilities

I welcome the emphasis on national-scale research facilities: I was Chair of the taskforce that delivered the 2016 National Research Infrastructure Roadmap.

This year’s budget invests $1.9 billion over 12 years, adding to the $1.5 billion over ten years committed to the National Collaborative Research Infrastructure Strategy (NCRIS) in 2015.

As shown below, $393.3 million is allocated in the next five years.


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I am encouraged that the government has committed to review the investment plan every two years, in recognition of the importance of keeping this discussion firmly on the national agenda.

In addition to these funds, the budget acts on an urgent priority flagged in the Roadmap – high performance computing. $70 million for the Pawsey Supercomputing Centre in Perth adds to the $70 million previously committed to the National Computational Infrastructure in Canberra.

This builds on the $119 million announced for the European Southern Observatory in the previous budget.

National missions

A second notable feature is the follow-through on the national missions proposed in the Innovation and Science Australia (ISA) 2030 Plan.

The ISA mission to preserve the Great Barrier Reef is supported by $100 million in new investment for coral reef research and restoration projects, as part of a $500 million package announced last month.

The ISA mission to harness precision medicine and genomics to make Australia the healthiest nation in the world is backed with $500 million over the next ten years from the Medical Research Future Fund.




Read more:
Four ways precision medicine is making a difference


A scaffold for the genomics revolution was provided by the Australian Council of Learned Academies (ACOLA) in the recent Precision Medicine Horizon Scanning report, commissioned by the Commonwealth Science Council.

A forthcoming Horizon Scanning report, on artificial intelligence, will likewise inform the $30 million commitment to AI and machine learning in the 2018 budget. The funding includes a national ethics framework for AI – a welcome development that will position Australia well in the global AI standards debate.


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More broadly, the budget acts on priorities that scientists have championed for years.

There is $41 million for a National Space Agency, including a $15 million fund for International Space Investment.


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Over four years, $36 million will be provided for the Antarctic science program.

An amount of $4.5 million over four years is aimed to encourage more women into STEM education and careers, including a decadal plan for women in science.

With a focus on GPS technology, $225 million is allocated over four years to improve the accuracy of satellite navigation, and $37 million over three years for Digital Earth Australia. The goal of this funding is to make satellite data accessible for research, regional Australia and business.


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There is also $20 million for an Asian Innovation Strategy, including an extension of the Australia-India Strategic Research Fund for four years.

Business innovation

In the business arena, changes to address integrity and additionality (that is, driving R&D to levels beyond “business as usual”) in the Research and Development Tax Incentive (RDTI) will reduce by an estimated $2.4 billion the money the scheme delivers to industry.

As one of the authors of the “3Fs” review of the RDTI – with Bill Ferris and John Fraser – I support the rebalancing of Australia’s business innovation budget. We are a global outlier in our heavy reliance on the indirect pull-through achieved through the tax system, instead of mission-driven direct investment.

The ConversationWith money recouped from the RDTI, scientists and research-intensive businesses should be making the case for more and better-targeted programs. Work remains to be done.

Alan Finkel, Australia’s Chief Scientist, Office of the Chief Scientist

This article was originally published on The Conversation. Read the original article.