ORIGINS SPACE TELESCOPE (OST)
This is what the birth of stars looks like The OST telescope, whose acronym stands for
Origins Space Telescope is a telescope proposed by NASA which will aim to trace the history of
our origins from the moment when dust and heavy elements of the stars permanently altered the
cosmic landscape to the current universe. THE ORIGIN OF EVERYTHING
For decades, scientists around the world and space agencies have done their best to try to uncover
how the universe formed and what processes led galaxies and stars
to take the shape they do today. Several projects such as the Hershell
space observatory or more recently the James Web Space Telescope, which we have already
talked about in previous videos, "Introduce here image of the video on the JW telescope", have
as their main objective to study the most distant galaxies and stars of the
universe in the near and medium infrared. However so far the most distant and ancient
events in the universe are still not visible even to the most powerful telescopes, but why? Why is
it so difficult to observe the farthest events in the universe? And why is it said that the farther
we observe the more into the past we can observe? THE LIGHTS OF TIME
In the universe the light of stars and galaxies is scattered in the form of a wave,
just as when we throw a stone into the water, it produces waves that
propagate in all directions, the light of the stars still propagates in the form of a sphere
in all directions indefinitely and constantly. This means that no matter how far away a galaxy is
sooner or later its light will reach us and we can see them, however there is a problem and
that problem is that as light travels through the universe, the universe itself expands.
As you know, the universe is expanding, every second and every moment, for billions of years,
since the universe was born it began to expand and every time it does so faster. This is a
problem for light because as the light from the galaxies travels through the universe, the space
between the light waves expands, consequently the light waves of the galaxies are stretched.
The longer the light waves travel, the greater the distance in the universe, but in turn,
the universe also expands and consequently the light waves stretch, losing energy in the process.
This effect is what in physics is known as Redshift, also
called redshift. This effect causes waves that travel for a long time in
the universe to move towards the red strip of the electromagnetic spectrum
and the longer they travel through the universe, the greater their redshift.
This means that the farther away a galaxy is, the greater its redshift and the greater its
redshift will be, the more difficult it will be for telescopes to see since to see them it is
necessary to observe the waves of the infrared spectrum and to be able to observe in that
spectrum of light it is necessary to achieve very low temperatures in the observation instruments.
THE PROBLEM OF TEMPERATURE IN SPACE TELESCOPES Telescopes intended to observe in the infrared
light spectrum of the universe are designed to be able to work
under extremely low temperatures, the Hershell space observatory operated under a temperature
of 87°K, this is equivalent to -186°C or -303°F. The James Webb Space Telescope is designed to
operate at a temperature of 53°K, which is equivalent to -220°C or -364°F.
While the new OST telescope is designed to detect photons that are at a temperature of 5°K! To give
you an idea, 5°K equals -268°C or -450°F. In order to reach such extremely low
temperatures the telescope will require cryogenic cooling systems to actively cool the detectors
and optics of the telescope to 5K. This will reach sensitivities 100 to 1000 times higher
than any previous far-infrared telescope. The reason why all these telescopes must
operate at such low temperatures is that the infrared radiation that reaches us from the
most distant galaxies is very weak, dim and low energy, so in order to detect it it is necessary
that the instruments that are responsible for detecting them have low temperatures,
so that the radiation emitted by the equipment does not interfere with the measurements.
Thanks to the ability of the OST telescope to detect particles at very low temperatures,
it will be able to detect the light of the most distant galaxies in the universe
and will help us observe what the entire universe was like billions of years ago.
CHARACTERISTICS OF THE OST The future OST telescope is still
in the development phase and it is expected that its launch into orbit will be by 2035,
however it will present some similarities with telescopes already known.
Some of the most familiar features will be that the OST will feature a mirror sectioned
in hexagonal panels just like the James Webb telescope with the difference that the primary
lens of the James Webb measured 6.5 meters, the primary lens of the OST will have a diameter
of about 5.9 meters, smaller than the James Webb, but it will have technology and instruments
more focused on observing the distant universe. OST INSTRUMENTS
Initially, the basic design of the OST contemplates a load of 3 instruments, these are:
1. A mid-infrared transit spectrometer (MISC-T) that operates from 5-30 microns,
with resolving powers, R~100, 300 in three bands. (MISC-T) will measure the spectra of
transiting exoplanets in the wavelength range of 2.8 to 20 μm and offer unprecedented sensitivity,
enabling detections of definitive biological signatures in stars and exoplanets.
2. A far-infrared (OSS), medium-spectral resolution, direct detection spectrometer,
optimized for multi-object spectroscopy and large area mapping, spanning 30-600
microns. It will cover wavelengths from 25 to 588 μm, conduct deep and wide-area spectroscopic
surveys with spectral resolution power R 300, which will help it observe the deep universe.
3. A far-infrared broadband imager/polarimeter (FIP) operating in two bands:
50, 250 microns. The (FIP) will be able to measure thousands of square degrees with broadband images
at 50 and 250 μm, which will help you probe large areas of space in a very short time.
What makes the OST special is that it will be the first optical telescope
capable of observing in the far infrared,
previously other space telescopes such as spitzer or Hershell were able to observe
near-infrared radiation successfully, even the new James Webb telescope is capable of doing so.
But the OST telescope will be the first of its kind, an instrument capable of observing
the far infrared, which will reveal the oldest images of the entire universe.
The idea is not that the OST telescope replaces the James Webb when it is running out of fuel
but that both will work together observing the same region of deep space
at the same time, with different instruments, in different ranges of the infrared spectrum.
Origins was designed to minimize complexity. The telescope has a Spitzer-like architecture and
requires very few deployments after launch. The cryo-thermal system design leverages JWST
technology and experience. A combination of current-state-of-the-art cryocoolers and
next-generation detector technology will enable Origins' natural background-limited sensitivity.
MAIN OBJECTIVES OF THE OST The Origins Space Telescope would
perform astrometry and astrophysics in the mid- to far-infrared range focusing on observations
of exoplanets in the wavelength range of 3.3 to 25 μm, measure temperatures, and look for basic
chemical ingredients for life in the atmospheres of small, warm planets at habitable temperatures
(∼ 300 K (27 °C)) and will measure its atmosphere. Composition. This
can be achieved by a combination of transit spectroscopy and direct coronagraphic imaging.
Important atmospheric diagnostics include ammonia spectral bands (NH4, a single nitrogen tracer),
the 9 μm ozone line (ozone O3, is a key biosignature),
15 μm2 CO (carbon dioxide is a major greenhouse gas), and many wavelength bands of water.
Its spectrographs will enable 3D studies of the sky that will discover and characterize the most
distant galaxies, the Milky Way, exoplanets and the far reaches of the Solar System.
HOPES OF FINDING THE ORIGIN OF EVERYTHING The OST will be the first telescope in
history to be able to observe the far universe at far-infrared frequencies,
currently telescopes such as the James Webb or the Hershcell space observatory have observed
the universe only at near-infrared frequencies. Moving directly from the near infrared to the
far infrared will mean an unprecedented increase, even the estimates of scientists is that with this
range it is possible to observe the birth of the first stars of the early universe,
as well as the formation of galaxies. With this it is expected that astronomers
will be able to decipher the shape that the universe had in the past, it is currently
known that the universe expands and for billions of years the shape that the entire universe had
has changed a lot if we compare it with the shape it currently has.
With the OST we will be able to see the evolution that the universe has undergone
throughout its history, from when it was born billions of years ago to the present date.
ARE WE ALONE? Finally, one of the main missions
of the OST telescope will be to search for exoplanets that have the potential to host life.
Currently some telescopes such as the James Webb or the Very Large Telescope
have already been entrusted with this task, but we still have a long way to go to observe
the worlds with the best chances of hosting life, especially those that resemble the earth.
So far the most powerful telescopes are able to detect very large planets
the size of Jupiter or Neptune, but these are not the ones that interest us since
there can be no life in them as far as we know. The planets we are looking for are much smaller,
the size of the earth and so far we have only found a few, it is expected that the
James Webb Space Telescope finally managed to detect this type of planets, however we
will not know until it becomes operational. Another problem is that for now the best way we
have to detect exoplanets is when they pass right in front of their star when they are seen from
earth, that is, when a transit occurs, so that if the exoplanet does not cross in the view of
the earth it will not be possible to detect it. On the other hand, the OST telescope will have
a greater capacity to detect this type of planet since it will be able to observe the surrounding
areas around the stars, in this way it will be possible to observe the exoplanets of the stars
even if they do not pass in front of the light of their star.
This will greatly increase the number of detectable exoplanets and with some luck
we will find very Earth-like worlds, green and blue planets with large amounts of water where
life can arise just like on earth. If we find a world with these characteristics
our hopes of being able to find living beings outside the earth will increase considerably
and we will finally be able to answer the great question that our ancestors
asked themselves thousands of years ago when they looked at the stars: Are we alone in the universe?
The future OST space telescope will be a great advance in the way we observe the universe,
we can only hope that modern science and technology make it a reality.