To replace Hubble: an astrophysicist about the Russian-Spanish Observatory Spectrum UV and the search for exoplanets

- The project of the Institute of Astronomy of the Russian Academy of Sciences to create the Spectrum-UV Observatory will be supported by more than a dozen research groups from different countries. Can you talk about the significance of this space mission?

- This is the third project from the Spectrum series. The first was Spectrum-Radioastron, which had already completed its mission. In the summer of 2019, the Spectrum-X-ray-Gamma Observatory was launched, which entered a working orbit at the end of 2019. In October 2025, Spectrum-Ultraviolet, or Spectrum-UV, a joint project of Russia and Spain, which participates in its financing and provides its equipment, will be launched into orbit.

- Spanish colleagues will receive half the data?

- The financial contribution to this project is distributed approximately as follows: 80% from Russia and 20% from Spain. The same ratio and return.

- There is an opinion that Spectrum-UV will replace the Hubble telescope. How appropriate is this comparison?

- With the launch of Spectra-UV, we can say that we will be leading in this direction until 2035, because the mission of the Hubble telescope is ending. There were even groundless feelings in the Western press that Russia would have a monopoly on ultraviolet light and would not share it.

- Why baseless?

- The scientific program of the project has a complex structure. The first two years of the observatory will go under the basic program of the project of the Space Research Committee, led by Russia. The second half of the time is divided between Russia and Spain. But then the observational part will begin, applications for which will be accepted from any astronomers, not only participating countries.

- Does this mean that representatives of other countries will be able to conduct research as well?

- If the scientist is not from a participating country, but he has a wonderful idea about how to investigate a certain object of the Universe in ultraviolet, then he writes an application. It is considered by our committee. In case of recognition of its wealth to this specialist will be allocated observational time.

- Can we somehow compare the missions of Hubble and Spectra-UV? Whose benefit will the comparison be? Interested in the difference in research and the result.

- Despite the fact that the main mirror of our device is smaller than that of Hubble, a comparison may be in our favor. The diameter of the main mirror for Hubble is 2.4 m, and for ours - 1.7 m. The permeability we have should, in theory, be less. But we create equipment later, use a more efficient optical system, modern radiation receivers, so this difference is compensated.

• Hubble Telescope
• NASA

- What exactly is superiority?

- We surpass Hubble in efficiency at certain wavelengths. Another advantage is orbit. The Hubble flies in low Earth orbit - up to 600 km above the Earth’s surface. We will fly in a geostationary orbit of 35 thousand km. What is the advantage? We will study the Universe without a shell of near-Earth hydrogen, which interferes with observations in the ultraviolet, we will fly over most of its most dense layers.

- And as for the equipment?

- There are high and low resolution spectrographs, a set of new field cameras that take pictures of the sky in ultraviolet light. According to our estimates, we are slightly superior to Hubble in terms of efficiency, but we are talking very carefully about this. We prefer to say that we are at the Hubble level.

- What is the importance of the mission?

“This will be the only window in space exploration using ultraviolet radiation after the Hubble shuts down.” The next mission of the Americans - even with their gigantic finances - will appear only after 2035. That is, for about ten years in astrophysics there will be the only telescope that observes space in ultraviolet radiation using high-resolution spectroscopy.

- Now the boom of searching and studying exoplanets has begun. How will the new Russian observatory help in these studies?

- The study of exoplanets comes to the fore in astrophysics. You can draw some conclusions about the composition of the exoplanet, whether it has an atmosphere. For this, ultraviolet is just indispensable.

- Is it possible to find signs of life on exoplanets using the Russian observatory?

- Indirect signs of the existence of life on the planet may be biomarkers in its atmosphere: oxygen, water, carbon. It is difficult to detect them, but we would like to. We cannot guarantee the discovery of such planets yet, but we will try.

- To study exoplanets, will you use the coordinates of those that are already open?

- Right. To search for an exoplanet around a star with such instruments as ours is completely inefficient, therefore we will work on specially selected targets.

- What can you say about the 14 international research groups that are joining the project?

- Such scientific programs require several years of preliminary ground preparation, since the time of using the orbital telescope is expensive. In 2019, we announced the collection of applications for the scientific and basic program. This was done for teams led by Russian and Spanish scientists, but there may be employees from different countries.

- How is such an application drawn up?

- An application to the committee is being prepared, it is approved. The time of using the telescope next year is allotted. The preparation procedure is lengthy. About three dozen applications were received, 14 of the most interesting were selected.

- What other space missions of Russia are worth mentioning?

- There is a powerful lunar program in Russia, which involves the study of the moon, its atmosphere, the search for water. The launch of the lunar landing mission is due next year. Two years later, the lunar orbital mission starts, which will prepare the next lunar landing.

• In 2021, the launch of the lunar landing mission should be carried out
• © Roscosmos

- Can we say that Russia has a very ambitious lunar program?

- With the launch of Radioastron, we returned to scientific space. When we realize the landing mission on the moon next year, it will be possible to say that we have again taken strong positions in the scientific space. The project is in the highest degree of readiness, the equipment passes the last stages of testing.

- How is the interaction of scientists from different countries in the field of astrophysics? Is it more likely cooperation or rivalry?

- Rather, exceptional cooperation among scientists. The Americans understood that the Hubble would stop functioning. We were very interested in their experience with ultraviolet radiation, with objects, with calibrations. We even discussed their quota. Initially, there was a very great desire of scientists. However, when NASA was already supposed to participate in our project, the sanctions of 2014 came and the cooperation ceased.

“Did the story of coronavirus somehow influence the work of astrophysicists?”

- The epidemic has affected. And very much! In Spain, everyone settled home, and this country is a supplier of key elements of radiation receivers. We expect delays in deliveries.