Although NASA launches the next large space telescope in 2018, when the aging Hubble retires, we will lose our vision of the ultraviolet Universe.
For a whole generation, Hubble served as a window into the deep and dark secrets of the universe. From the visualization of volcanoes on the satellite of Jupiter Io to the observation of the dramatic decay of comets, emerging galaxies, and help in determining the age of the Universe. Its data play an important role in the modern understanding of the near and far space.
But the telescope is outdated, and since its last visit in 2009, no one supports it. Although the observatory is now in excellent condition, data collection will cease in the 2020s. What will we lose with his “resignation”?
At NASA, they quickly pointed to the Webb telescope, which is scheduled to launch in 2018. He is expected to increase the capabilities of Hubble. But with high resolution and the ability to peer into the very first days of the Universe, he lacks one possibility: the ultraviolet potential. (Also, he will not have Hubble's fine spectral resolution and ability to observe a special H-alpha line useful for nebulae and stars).
Astronomers are reminded of the ultraviolet capabilities of Hubble, because with his death they will not be something to replace. The earth's atmosphere protects us from ultraviolet radiation, but this is bad for astronomy, so the shooting should be done from space. Scientists assume that it is unlikely that a new ultraviolet telescope will be launched by the year 2030.
“For example, if we are observing stellar and planetary formations, then we need to see gas growth for them,” said Adam Kraus, an astronomer at the University of Texas at Austin. He explained that when gas falls on budding stars and planets, they emit most of their energy and ultraviolet waves. Unlike Hubble, Webb cannot see this.
The James Webb Space Telescope (shot during the inspection of the mirror) will improve Hubble’s observations in many areas, but it lacks ultraviolet capabilities - NASA / MSFC / David Higginbotem
Jane Rigby, deputy supervisor of Webb's operations, indicates that the new telescope is designed for scientific research that Hubble is not capable of. Webb has 7 times the collection area, and also works near absolute zero (the lowest possible temperature). It will be able to consider dusty places where stars and galaxies form, which are in a deep “red shift” (spectral lines moving towards the end of the spectrum) due to cosmic expansion.
Fortunately for astronomers, it is expected that the time of Hubble and Webb in space will intersect. Hubble has a large archive of observation and Webb could spend time watching the famous “deep fields” of young galaxies.
There is also the potential to create stereoscopic or “3D” images of several objects, since the Hubble (in low earth orbit) will be millions of miles further from Webb. At the Space Telescope Science Institute (STScl), the manager of the Hubble, some astronomers suggest that you can shoot the nearest objects.
“You could see the rings of Saturn sticking out of flat pages, Mars in the form of a globe or Jupiter and the movement of its moons,” said STScl project scientist Joel Green. “But you probably want to take a look at how these familiar cloud structures will change in 3D.”
It will also be possible to observe the explosion of the star (or supernova) and, thanks to the distance of the telescopes, find out where the explosion originated and study its features.
Hubble's ultraviolet capabilities are not found in any modern telescope. The photo shows possible water jets in Europe (opened this year) using Hubble UV filters - NASA / ESA / B. Sparks (STScI) / USGS Astrogeological Research Center In addition to Webb, other observatories are planned. One of them is the Wide Field Infrared Survey Telescope (WFIRST), which will use Hubble equipment with a wider field of view. His specialization will be dark energy and exoplanets. Another example is the transit search satellite exoplanets (Transiting Exoplanet Survey Satellite - TESS), focused on planets passing in front of the brightest stars in our sky. It is going to be launched in the 2020s, if the mission’s funding is fully approved.
But the next generation of mechanisms is still under development. In scheduling tasks, NASA relies heavily on the National Science Foundation, which arranges review every 10 years. Now the proposals are in the development stage, before presenting them to the members of the next meeting, which will take place in 2020.
This will be a real battlefield, thanks to which the future of ultraviolet astronomy will be determined. NASA plans to present four conceptual studies to the commission, including the mission of the Greater Ultraviolet / Optical / Infrared Search (LUVOIR). His abilities will allow to observe at once several wavelengths.
If it is launched, it will study the protoplanetary disks, will find and make images of black holes, create the Milky Way map, and even be able to examine the nearest exoplanet atmosphere for signs of habitability. But it competes with other missions, some of which are focused on infrared light (Far-IR Surveyor), X-rays (X-ray surveyor) and more modest ultraviolet and optical observers (HabEx). The latter can use a special separate shield to filter out starlight for direct observations of the planet, so that it would be the first case in astronomy.
Interpretation by the artist of the mission to search for a habitable exoplanet, which is still on the drawing board and not approved for funding. This is a possible successor to the Hubble skills on top of the current James Webb Space Telescope - JPL / NASA
“We hope that in 2020 one of these missions will receive funding,” said NASA's chief research officer for the exoplanet research program, Karl Stapefield. According to him, the goal is not only to study the nearest stars, but also the rest of the Universe.
There are also other ultraviolet telescopes: Advanced Technology Large Aperture Space Telescope (ATLAST), which was considered at the last commission and the High Definition Space Telescope (HDST). So there are many options.
While discussions are underway, Webb is preparing to launch. Rigby very much hopes for the scientific potential of the telescope.
“Look at Webb’s path, and you’ll see that it was developed as a Hubble legacy,” she said. “We’ve added everything that Hubble cannot do.” But what he did looks so elegant. The Webb Observatory is optimized in a completely different direction, because Hubble has already given us 25 years of observations within the range of its capabilities. ”