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.

NASA-related or aligned research interests as of 14 November 2022

This is an excerpt of an email I sent (12 December 2022) to representatives of the New Zealand Space Agency, which is a part of New Zealand’s Ministry of Business, Innovation and Employment. This was to highlight the areas in which I have active research or see potential areas of research overlap with NASA. This summary was prompted by the then interest in supporting NZ-NASA collaborative research. The following list of projects is, of course, not a complete list of NZ-NASA projects or linkages — it is only a list of projects in which I am involved or of which I know. MBIE funding to support NZ research involving NASA must find alignment with the Aotearoa New Zealand Aerospace Strategy. I have, where possible, shown where that alignment can be made.

The research collaboration arrangement between NASA and MBIE was solidified in 2023 around a limited range of research, those of “of natural hazards, water and climate modelling, environmental monitoring, and biodiversity”. The funding was provided via MBIE’s Catalyst: Strategic — New Zealand — NASA Research Partnerships 2023. Regrettably, none of my research areas I list below have strong resonance with these selected topics.

EXCERPT BEGINS (date of writing 9 December 2022)

The Nancy Grace Roman Space Telescope (NGRST, formerly WFIRST)

The Roman telescope will be the first space telescope dedicated to the use of gravitational microlensing for the discovery of extra-solar planets. New Zealand researchers have been active in this field for over 25 years. Members of the NZ-Japan-US Microlensing Observations in Astrophysics (MOA) collaboration are also involved with the NGRST microlensing programme. Principal among these is Professor David Bennet (NASA/GFSC). I have been working with Dave for as long as I have been a member of MOA, which is now over 20 years. Regrettably, this research finds resonance with none of the goals in the Aotearoa New Zealand Aerospace Strategy. However, one might argue that supporting New Zealand’s engagement with such a high profile NASA mission would support MBIE’s aim of [g]rowing an innovative and inclusive space sector. On that website, take a look at the evocative and inspirational image of the young person using a telescope. Imagine upgrading it with an image comprising NZers engaging in research with NASA’s flagship Nancy Grace Roman Space Telescope!


I am funded through a grant to Dr Rich Barry (NASA/GFSC) to perform preparatory simulation work for the Contemporaneous LEnsing Parallax and Autonomous TRansient Assay (CLEoPATRA) space mission concept. CLEoPATRA is designed to provide variable-baseline simultaneous microlensing parallax measurements for NASA’s flagship Roman Space Telescope mission and for terrestrial telescopes.

Free-space optical communications

The MBIE-DLR Catalyst grant for FSOC which I am leading is making progress. Advisers to the Australian Optical Communications Ground Station Network Working Group — of which we are a part — include Ed Kruzins, who works for the CSIRO NASA Operations & Canberra Deep Space Communication Complex (the Deep Space Network). NASA conducts research into optical communications for deep space exploration, and this is an area into which New Zealand could expand, in conjunction with NASA. An interesting opportunity exists in which the Warkworth 30m radio dish could be teamed with an optical communication terminal to conduct hybrid communication experiments with NASA spacecraft. I had a recent discussion with Robin McNeill (Space Operations New Zealand) about the prospects of using Warkworth as part of an expanded DSN. This work matches Strategy Goal 4: Actively support a permanent human presence in space.

Space Situational Awareness

One area in which our optical communication research could be expanded is into the optical imaging of space assets and debris. Steve Weddell and his team at UC are active in this area. As part of my FSOC work, I am aiming to develop infrastructure to mirror the capability that the DTA has for tracking space craft. This work would naturally service the need of SSA orbit determination and trajectory analysis, but it would also provide valuable information for those of us interested in quantifying the effect of satellites on the night sky — work on which I am involved along with Dr Michele Bannister, UC. The optical tracking of space assets and debris is an active area of research at NASA. Research into making and using optical observations of space debris and assets resonates strongly with Goal 3: At the forefront of global sustainable space activities.

Planetary Defence and Space Weather

Michele Bannister (UC) and Craig Rodger (UO) conduct research into the space environment. Michele has projects into environmental degradation, and Craig researches space weather. Both of these are areas in which NASA is active. I note that Michele most recently was involved in using the MOA 1.8m telescope to attempt observations of the NASA DART mission, following its impact into the asteroid Diamorphos, as part of its planetary defence programme. I would argue that Goal 4: Actively support a permanent human presence in space, encompasses this class of research, which supports the continued human presence in space as inhabitants of planet Earth in the face of astrophysical hazards.

Mars Surface research

Professor Kathy Campbell has engaged with NASA in relation to the choice of landing sites for Mars surface sample return missions. Kathy and I are part of the Executive Team of Te Ao Mārama Centre for Fundamental Inquiry. At our recent workshop, we discussed the prospect of developing links with NASA in astrobiology research.

Balloon Projects

A cheap and fast route to space is via balloon launches. NASA’s Scientific Balloon Program has been active for years in New Zealand. I would be very keen to see links developed with the Program, as this would be a means by which New Zealand could engage with space projects at lower cost, and with shorter timeframes than through orbital space missions.

NASA’s Small Satellite Mission Directorate

In the past I have spoken with Christopher E. Baker (Small Spacecraft Technology Program Executive within the Space Technology Mission Directorate) about New Zealand working with NASA on small satellite development.

Microlensing parallax

I am doing a little work in microlensing parallax between two observatories. First step: replicate others’ work! Here is my attempt to replicate Figure 1 of Henderson & Shvartzvald (2016).

And here is Figure 2:

Figure 3:

Here is a scatter plot of mu_rel for $D_l = 1$kpc and $D_s = 8.2$ kpc, with the bulge velocity distribution used for the lens:

Animation of the positions of Earth and Kepler, in 2022, projected onto the observer plane, pointing towards a source at the centre of the K2 superstamp:

Plot of theta for Kepler-Earth, over a year:

Using the same assumptions as H&S, here is their Figure 3 replicated:

Here is some work going beyond H&S Figure 3, using the samples from the actual observer ephemerides along with the Galactic model draws:

Here is Figure 4 replicated:

Here is Figure 6 replicated:

Here is a first attempt at characterising the type of lenses that Cleopatra will be sensitive to:

Here is a final set of relative sensitivity histograms for a 20cm and a 50cm primary mirror, for two different values of d_perp, two different min(Amax) values and two choices of minimum sampling:

Observation Planner

While there are any number of excellent software products available to help an observer plan an observing session, I was more interested in producing a single image that could give an idea of what objects were in prime viewing position.

Using astroplan, astropy, adjustText and jplephem, I have a first attempt done.

So far the code will plot out the maximum altitude of a set of objects, as seen from an observer’s position on Earth, as a function of the day of the year. I gave some indicative altitude curves for some objects, to get a sense of their position change across their maximum altitude. The small number at the start of each curve is the azimuth.

The input is currently one of the Messier and NGC catalogues, but any list of objects can be included as a csv file. The object needs to be resolvable via astropy’s SkyCoord call.

Maximum altitude of Messier objects, Auckland, NZ at UTC 1200 in 2022. Times of new moon are shown with dashed vertical lines.

Astrophotography observation planning

I’ve been having some fun using the astroplan library to predict when are the optimal times in the year to observe some deep sky objects. Here is a sky plot for M6 as seen from Auckland, New Zealand.

Sky plot of M6 as seen from Auckland, at local midnight on the first of each month, 2021.

The full sky plot is useful to me as half of my sky is blocked by either buildings or suffers extreme light pollution. The eastern sky is best for me. So this pushes me towards May/June for observations.

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