The Hubble Space Telescope was visited by astronauts between 1993 and 2009 during five space-shuttle missions. Here, two space astronauts work on Hubble during the first maintenance mission, fixing the telescope's mirror and installing a new camera.
When it comes to telescopes, size matters.
To keep learning about the universe, astronomers are increasingly interested in building larger and better observatories to view the cosmos from both Earth and orbit. Engineers have already begun developing the technology needed to build the next generation of the latest generation of space telescopes, but there is only one problem: these observatories may be too large to enter space.
Both in terms of size and weight, the telescopes astronomers and engineers are already planning for the future, the capacity of today's rockets quickly. This is because the capabilities of a telescope largely depend on its aperture or the diameter of the main mirror. New mega-sockets, such as NASA's Space Launch System, are big enough for the next generation of space telescopes NASA plans to launch in the 2030s, but if subsequent missions must squeeze into the same size rocket disguise, these missions must Victims bring some scientific potential. [Giant Space Telescopes of the Future (Infographic)]
Rather than limiting the design of a telescope to fit into the payload fairing of the largest available rocket ̵
"Large telescopes offer you better angular resolution and better spectral resolution so larger telescopes should be built in the future." Nick Siegler, chief technologist at NASA's Exoplanet Exploration Program, said at a presentation at the 23rd session of the American Astronomical Society in January in Seattle. With this higher resolution, telescopes can see more of the universe, look deeper, and see more clearly than ever before. It will also be especially useful for finding and characterizing planets around other stars.
"Of course," big "is relative, but the challenge that develops is the same," Siegler said. "They have large structures that you try to fold into smaller structures, and the amount of work you do is enormous." For example, NASA's James Webb Space Telescope (JWST), which is currently scheduled to launch a heavy-duty Ariane 5 rocket missile in 2021, is collapsing to fit into the missile's payload fairing. When the telescope is operational, more than 200 moving parts must unfold carefully before the instrument can work with the observation of the sky.
JWST will be the largest space telescope ever launched in space with a 6.5 meter mirror. The Ariane 5, which JWST will launch, is a heavy rocket that is normally used to launch satellites into orbit. However, these missiles also launched interplanetary missions, such as Mercury's BepiColombo mission of the European Space Agency for Europe, launched last October. Although JWST has not yet launched, NASA scientists are already working on proposals for their successor. (Spoiler Alert: They're even bigger than JWST!)
NASA engineers working on designs for planned space observatories such as the Large UV Optical Infrared Surveyor (LUVOIR) and the Origins Space Telescope (OST) were already struggling with the limitations of today's rockets. For each of these two telescopes, the engineers had two different design options: a 15-meter version, which can be launched with NASA's upcoming Space Launch System (SLS), and an 8-meter version (26-foot version) launch on today's smaller and less powerful heavy rockets. These smaller versions are NASA's backup plans in case the SLS is not ready on time. The Megarocket has already struggled with significant delays and cost overruns.
Astronauts vs. Robots
Rather than waiting for someone to build a rocket big enough to support the kind of space telescopes scientists want to launch in the future, a team of NASA researchers is exploring the possibilities of mounting in space. This process would not only remove the obstacles associated with rocket size, but could also reduce the cost of developing and launching new space telescopes, a description of the study "In-Space Assembled Telescope" (iSAT) said.
Finding out how to build a telescope in space is just the beginning. In order to make space telescope assembly a reality, NASA has to prove that the process is not only possible but also cost effective and not too risky. These factors depend largely on whether the assembly is performed by astronauts, robots, or a combination of the two that members of the iSAT team declared at the AAS meeting.
Sending astronauts to work on a space telescope is not a new concept. NASA's iconic Hubble Space Telescope, launched in 1990, was serviced five times between 1993 and 2009 by astronauts. Although the astronauts did not originally build Hubble, they installed some new equipment and made some important repairs to the observatory. No other space telescopes have been visited since the last Hubble maintenance mission.
While the space shuttles that flew on Hubble maintenance missions have been down since 2011, NASA has been able to send astronauts from the Lunar Orbital Platform Gateway. This planned space station in the Moon Land would serve as a springboard for future missions to Mars.
But some researchers, such as Siegler, think that robots are better for building things in space. "Astronauts are expensive," he said. "We believe we can do it completely robotically." A robotic system for the construction of a telescope in space would behave in a similar way to the robotic arms of the International Space Station.
This summer, the iSAT team plans to release the latest results of its study on various options