UV space telescope for exoplanet atmosphere discovery

This post sets out the reasoning behind my statement, made during a Te Ao Mārama seminar:

New Zealand has the capacity to design, build, test, launch and operate a space telescope capable of detecting atmospheres on alien worlds.

  1. For alien life to exist on the surface of a world, we postulate that the world must have an atmosphere,
  2. There are thousands of exoplanets known for which we can try and detect an atmosphere,
  3. The presence and constituents of an alien world atmosphere can be determined using spectroscopy, during planetary transits,
  4. Some of the strongest evidence is found at ultraviolet wavelengths,
  5. UV observations of this type have to be made in space, because Earth’s atmosphere blocks UV light,
  6. New Zealand researchers have long experience with exoplanet detection science and spectroscopy.

So a space telescope, operating in space and optimised to collect spectroscopic data in the UV, is what we’re proposing.

  1. Funding in New Zealand is scarce for fundamental research,
  2. Space missions are expensive,

So if New Zealand wants to fly a fundamental science mission in space, it needs to be as cheap as possible.

  1. Rocket Lab (and other launch providers) can deploy satellites to orbit as so-called “ride-share” missions. This is a relatively cheap method for getting craft into orbit,
  2. Rideshare spacecraft are typically built according to the “CubeSat” standard; a prescription that makes the acceptance of a spacecraft as a rideshare mission more straightforward,
  3. Building a telescope into a CubeSat requires either (i) chopping up the primary mirror to fit wholly within the CubeSat frame, or (ii) having a mechanism that deploys a telescope optical assembly, or (iii) using ultrafast optics, such as a monolithic telescope,

This is not a new idea: The Colorado University Space Telescope (CUTE) is currently in orbit and collecting data, in the UV, from a CubeSat comprising a truncated primary mirror. The CUTE utilises option (i), above. Option (i) is simpler mechanically, but in cutting up the telescope primary mirror, you lose light collecting power. Option (ii) allows for a larger primary mirror, but requires a deployment mechanism (already a risky prospect) to operate flawlessly and arrange itself to within optical tolerances (which are very tight). Option (iii) looks like a promising means by which a telescope can be formed out of a monolithic block of silicon and in which the reflecting surfaces are guaranteed to be always aligned.

Research is ongoing at Te Pūnaha Ātea Space Institute into designing a deployable telescope baffle — i.e. exactly what is need for option (ii). The image below shows the research idea, showing a CubeSat telescope with a deployable baffle.

Background image credit: ESA. Telescope image credit: NASA
–Background image credit: ESA. Telescope image credit: NASA

I am interested in seeing what can be done with a monolithic telescope design — can this be used to feed a spectrograph sufficiently well to perform the transit spectroscopy for discovering exoplanet atmospheres in the UV?

  1. New Zealand has a long history of telescope optical design,
  2. Kiwistar Optics Ltd could be a local partner in this research.

So we have local expertise in exoplanet discovery research, local expertise in spectroscopy, local expertise in telescope manufacture, a space institute ready to help build and test a spacecraft and a locally available launch provider. The ingredients are all there to design, build, test, launch and operate a space telescope capable of detecting atmospheres on alien worlds.

What we lack is funding, as usual.

NJR Honours Projects for 2018

Here’s my list of Honours projects for 2018. If you are keen to do one of these, please email me or drop by to discuss.

1. University of Auckland Ground Station 1

The University’s first CubeSat mission is scheduled to fly late 2018. We have a ground station on top of the Physics building to communicate with satellites. This station requires final calibration and testing, and development of corresponding control and analysis software. This work will be done in conjunction with the Auckland Programme for Space Systems, using the new APSS laboratories on Symonds Street and the Department of Physics Electronics Laboratory. You will be working with students and staff in the Faculty of Engineering, as well as in the Faculty of Science. You will also assist in the preparation to communicate with the first APSS satellite mission via the Defence Technology Agency’s ground station, working with DTA staff to ensure a smooth connection between the DTA systems and the University network.

This will be of interest to you if:

  • you have a reasonable grasp of radio communications,
  • good electronics / lab skills,
  • good computer network skills,
  • excellent written and oral communication skills,
  • an interest in space system hardware.
Listen and track satellites and help us get ready for launch in 2018!

Listen and track satellites and help us get ready for launch in 2018!

 

2. Hauraki Gulf Space Observation Honours Projects

Coastal science is both complex and complicated. There is a lack of detailed information on the interaction between ocean and coast, the coastal ecology and the relationships between the coastal environment and life on and near the coast. Each of the following projects relates to an overall goal of imaging the Hauraki Gulf from space. These earth observation projects are multi-disciplinary and will be carried out in conjunction with the Department of Marine Science and the Department of Engineering Science in the Faculty of Engineering.

2a. Geosynchronous CubeSat Feasibility Study

For this project you will scope and design a small satellite system that is capable of imaging the Hauraki Gulf to a few metres resolution from a geosynchronous orbit. These image data will be used to measure coastal sea colour, elevation, turbidity and reflectance. You will need to investigate commercial off the shelf optics and imaging systems that can provide the necessary resolution, and can operate within the power, volume, mass and communication bandwidth budgets of a small satellite system bus. You will need a good grounding in optics, electronics and some signal processing. Experience in space systems is not required. You must have excellent written and oral communication skills as you will be required to interact with a range of individuals both across different University Faculties and Departments, as well as external hardware and service providers.

This will be of interest to you if:

  • you have an interest in space system mission design,
  • good electronics / optics skills,
  • familiarity with signal processing and data analysis,
  • excellent written and oral communication skills.

2b. Earth Observation Satellite Data Analysis

This project will require you to make a census of the available satellite imaging and radar data of the Hauraki Gulf. A number of existing satellite missions make their data freely available, such as ESA’s Sentinel optical and synthetic aperture radar satellites. You will investigate what sources of data are available, summarise basic meta data of each data source (e.g. how often images are taken, wavelengths, resolutions, etc). You will work with satellite imaging experts both in Auckland and at the Centre for Space Science Technology to identify modes of imaging that will provide the information required to address the science goals of the project — or identify a need for more imaging. You will also use existing analysis software to do preliminary data analysis for suitable datasets.

This will be of interest to you if:

  • you have an interest space-based data analysis,
  • very good programming skills,
  • familiarity with image analysis,
  • excellent written and oral communication skills.

 

3. Design a UV space telescope mission to detect intermediate mass black holes

Intermediate mass black holes are theorised to exist in our Galaxy. They are difficult to detect, however. One channel for discovery is by looking for tidal disruption flares (TDFs), wherein a companion to a black hole is disrupted the the gravitational distortion of the BH and emits bursts of radiation. These transient events are highly energetic, but emit most of the radiation in the UV, making ground-based observations only sensitive to the brightest events. This project will be to design a small satellite to make UV observations from space, in order to detect fainter TDFs. You will be working with colleagues at The University of Warsaw.

This will be of interest to you if:

  • you have an interest in space system mission design,
  • you have a good background in — or at least a strong interest in — astronomy or astrophysics,
  • good electronics / optics skills,
  • excellent written and oral communication skills.

 

4. Astronomical Seeing Measurements in the Greater Auckland Area.

One of the Department’s 40 cm Meade telescopes has been converted into a seeing monitor. Seeing is a measure of atmospheric turbulence. This project will involve the student making seeing observations at various sites in the Greater Auckland area, analysing the results and publishing these. The student will have to be comfortable working at night, and have a full driver’s licence. You will make seeing measurements using the dedicated software written for the instrument, as well as a commercial seeing analysis package and compare the results.

Use one of these!

 

This will be of interest to you if:

  • you have an interest in astronomy,
  • very good programming skills,
  • familiarity with image analysis,
  • excellent written and oral communication skills.

 

5. Multidimensional Dataset Visualisation with an Oculus Rift

This project will require the student to investigate multidimensional astronomical datasets using an Oculus Rift. Students should have a high level of programming ability. You will be using the iViz visualisation software from Virtualitics (no experience necessary).

This will be of interest to you if:

  • you have an interest in data analysis, and human-computer interaction,
  • excellent programming skills,
  • excellent written and oral communication skills.

Oculus Rift DK2

 

A Visit to CalPoly to learn how to build CubeSats

The California Polytechnic State University — CalPoly — is in the pretty town of San Luis Obispo, a four hour drive north-west of Los Angeles. It is the home institution of one of the two academics who defined the CubeSat small satellite form factor. Every year CalPoly hosts a conference bringing together academics, industry, educators and students who are eager to use the CubeSat technology as a cheap way of conducting a space mission.  This year’s conference was the 14th in the annual series and was the most well attended to date, with around 300 attendees.  Around half of the audience was from academia or other educational institutions and the other half from the aerospace industry. The three of us who attended constituted one of the largest delegations from a foreign university.

The CubeSat standard has produced an industry providing CubeSat format compatible satellite subsystems — most of which are advertised as being “plug and play”. However of course the reality still is, as they say, space is hard. Space is also expensive.  For these reasons we need to learn as much as possible how to design, construct and test small satellites. It’s well-known that, after over a decade of launching CubeSat space missions, around 50% of those launched from student teams do not function upon arrival in orbit. The reason for this is usually attributed to a failure to test the satellite sufficiently well before launch. Our tasks at the conference was, therefore,  to listen, learn and talk to as many people who we think would be able to advise us as we start on this perilous journey into space. We had the opportunity to listen to many speakers on their experiences launching CubeSat based space missions.  Some of the talks were from industry-based enterprise and some from academia and indeed some from high schools. The advantage of a CubeSat is that it is a  relatively cheap platform around which to base a space mission.  They are small and therefore are usually modest in the scientific returns.  However they can be designed and constructed at relatively low cost and relatively quickly. This allows CubeSats to take advantage of technological innovations at a far greater rate than traditional large space missions. By the time a traditional large space satellite is launched the technology is already some years out of date as engineering requirements would have had to be specified and set in stone some years before launch.  This is not the case with nanosatellites such as a CubeSat, indeed some of the first  small satellite missions simply flew a commercial cell phone into orbit, the so called PhoneSats.

We were able to talk to several people who are a particular interest in our work with the APSS. Brad Schneider (VP/General Manager Rocket Lab USA) was there and we had a good chat with him.  Brad was able to update us on the status of Rocket Lab’s operations at their launch site at Mahia, as well as giving us an idea of the scale of Rocket Lab’s operations in the US. We also caught up with the CEO of Clyde Space, Craig Clark, MBE. Clyde Space is supplying our first CubeSat system, functional and ready to incorporate a small student payload. We found Craig to be very supportive of our new programme and stands ready to help us out as far as possible.

NASA has long recognised the value of small satellites and indeed CubeSat space missions as a means for demonstrating new technologies quickly and relatively inexpensively. There were a number of topics of interest in small satellite technology development expressed at the conference.  One of the biggest challenges to small satellite space missions is the inability to transfer large amounts of data collected in space down to Earth.  Power restrictions and bandwidth often mean that the data downlink from satellite to Earth is somewhat modest.  There is therefore a great deal of interest in optical communication systems which could allow small satellite space missions to download more of their data.  One of the most ambitious programs of this type is to perfect a system of laser communication between a small satellite and a telescope on Earth.  The predicted maximum data rate is expected to be of the order of a gigabit per second.  Other technology challenges which are being currently addressed by the community include propulsion systems for small satellites. This is of particular interest as small satellites are being considered for missions well beyond low earth orbit.  Missions are being designed to travel to Mars and the moon.  Finally as an example firmly in the realm of cutting edge technology, there is a program being run by the University of Singapore to enable Quantum Key Distribution. QKD is a technique which, if successful, will utilise the phenomenon of quantum entanglement to improve encryption. Satellites will generate entangled photons and distribute these to the well-known correspondents Alice and Bob. Essentially creating a one-time pad, QKD offers a means by which that miscreant Charlie will be fresh out of luck in eavesdropping on their conversation. There is therefore a great deal of opportunity for universities and research institutions to develop small satellite subsystem technology.  Nanofluidics, biological experiments, laser communication, material science,  computer algorithm design, were all the basis of small satellite enabled missions described at the conference.  Apart from work developing new technologies is the drive to miniaturise current technologies to operate on a small satellite. Delwyn Moller (Principal Systems Engineer, Remote Sensing Solutions and UoA Engineering alumnus), at a talk given at the UoA earlier this year, mentioned that her company is working on miniaturising their radar system to fit within a CubeSat.

There is, therefore, a great interest in the community in developing technologies for flight on CubeSats. These subsystems are necessarily small and will have a very high cost per kg, ideal for a country like New Zealand, remote to most major consumers of small satellite technologies. There are significant research programmes at the UoA that could take part in developing CubeSat technologies, including the laser and quantum optics groups in the Department of Physics; the robotics, electronics, mechatronics groups in the Faculty of Engineering.

And in addition to this there is always the opportunity to use small satellites to engage students in STEaM subjects at university, in the way that we are doing with the APSS.  There were a couple of talks at the conference which described the work done by university and high school CubeSat based programmes. One of the more impressive outfits is Auburn University, which has been running a small satellite programme for some time. They note that the advantages of the programme include the excitement space brings to the student environment, as well as a sense of community. Challenges include the maintenance of motivation of the students as well as the time expended and the continual loss of “corporate memory” as students pass through the programme. Motivation is heightened by a sense of ownership, which is in turn maximised by a degree of autonomy. A feature of this programme is that the students are divided into management teams and technical teams, depending on their skill sets.

The Vice President  (Engineering) of AMSAT was present at the conference and demonstrated how easy it was to listen to the AMSAT satellite as it passed overhead on day 2 of the conference.  One of us (NJR) forced the others to suffer rush hour LA traffic to get to an amateur radio shop in Anaheim to buy an antenna rotator, which will be an integral part of a UoA satellite ground station.

 

Nicholas Rattenbury

John Cater

Jim Hefkey

 

May 2017