Astronews Recent Space News Discoveries (Nasa 2028-2030 Missions, Ganymede, The Milky Way,
& More)
Welcome to the eighth review of "Space and Astronomy" news, selected for you by Insane
Curiosity Channel.
The news, which will be weekly, will try to provide a quick overview of everything interesting
that has happened in recent days in the field of astronomical research and space exploration.
Keep following us!
Nasa
has announced the two new missions selected for the Discovery Program: they are the Venusian
Davinci+ and Veritas, departing between 2028 and 2030.
Remain behind instead the missions directed to the satellites Io and Triton.
If you remember, in February 2020, NASA announced the finalist missions for the Discovery Program,
the set of low-cost missions that since 1992 deepen the mysteries of our planetary system.
There were four: Davinci+ and Veritas directed to Venus, Io Volcano Observer directed to
the innermost of the four major satellites of Jupiter and Trident, the probe directed
to Triton that should bring us back in the systems of the icy giants after forty years.
Now NASA has announced the final selection, based on the study of feasibility and scientific
return of the missions.
It is Venus to win: Veritas and Davinci+ will leave in the launch window between 2028 and
2030.
Davinci+ (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging) is
a particularly fascinating mission: its goal is to study the formation and evolution of
the Venusian atmosphere, crossing it during the descent that will bring it to rest on
the surface.
Davinci+ will be the first probe to land on Venus since the Soviet Venera in the '80s.
Veritas (Venus Emissivity, Radio Science, InSar, Topography, and Spectroscopy) will
be instead an orbiter equipped with two instruments: a radar and an infrared sensor able to observe
the surface through the clouds and the dense atmosphere.
Among the objectives of the probe is the study of Venusian volcanism, to understand how active
it is today and how it has changed during the evolution of the planet.
Venus is an under-explored planet, especially when compared to our other planetary neighbor,
Mars.
At the dawn of the space age, the Soviet Union assigned 31 missions to the planet, but only
15 were successful and only some of these had a real scientific return.
Among these Venera 7 was the first in 1970 to touch the surface of another planet.
In more recent times, however, the interest in Venus has been much more limited: the only
data came from the European Venus Express, in orbit between 2006 and 2014, and the Japanese
Akatsuki, the only mission still in orbit around the planet.
After all, Venus is a planet really unapproachable, where the pressure is 90 times greater than
that of the Earth and the temperature exceeds 400 degrees Celsius.
A hell of carbon dioxide and sulfuric acid.
All characteristics that make it a difficult planet to explore, and in which the various
landers that have tried to descend have never managed to exceed a few minutes of operation.
But it is precisely these extreme conditions that make it interesting: Venus is considered
the twin planet of Earth, but has obviously had a completely different evolution.
Finding out why it has gone so and if the Earth is likely to become so in the future,
is the main objective of the next missions to be launched.
Next up, Juno probe has Ganymede in its Sights
These days NASA’s Juno probe is engaged in a close encounter with the Solar System’s
largest moon, Ganymede.
This will be the first flyby of the icy world since the Galileo and Cassini spacecraft jointly
observed the moon in 2000.
New Horizons also got a quick snap of Ganymede as it slingshotted around Jupiter on its way
out to Pluto in 2007, but from a distance of 3.5 million kilometers away.
Juno’s pass on Monday 7 will get much closer, approaching within 1038 kilometers of the
surface.
This pass over Ganymede is the first in a series of flybys past Jupiter’s Galilean
moons, which will collectively be the highlight of Juno’s extended mission.
The probe’s primary mission, which began in 2016, focused on the gas giant itself.
Juno has been taking long, highly elliptical orbits around Jupiter, diving close in to
collect data about the planet, before swinging way out again beyond the planet’s harmful
radiation, which threatens the spacecraft’s hardware if it stays too long.
The science goals for the encounter with Ganymede are wide-ranging.
Juno will, of course, take visible-light photos with JunoCam, which, besides being spectacular
to look at, will allow planetary scientists to observe changes in Ganymede’s surface
over time: the photos can be compared to Galileo’s from 20 years ago and Voyager’s from 40
years ago.
Ganymede is the only moon with its own magnetosphere, so Juno’s team is hoping to study it.
As Juno passes behind Ganymede, radio signals will pass through Ganymede’s ionosphere,
causing small changes in the frequency that should be picked up by two antennas at the
Deep Space Network’s Canberra complex in Australia.
If we can measure this change, we might be able to understand the connection between
Ganymede’s ionosphere, its intrinsic magnetic field, and Jupiter’s magnetosphere.
Juno will also use its microwave radiometer to examine Ganymede’s ice-crust, which will
tell us more about its composition, temperature, and structure.
Ganymede is a fascinating world.
Being larger than Mercury, with a diameter of 5300 km, it would be classified as a planet
if it orbited the Sun instead of Jupiter.
It’s also intriguing because it’s a water world, with liquid oceans beneath its surface.
This makes it one of the best solar system candidates for microbial alien life.
On the other hand, Ganymede’s ocean might not have contact with rock at its bottom,
instead being encased between two layers of ice sheets.
On Earth, the chemical reactions caused by water contacting rock provide energy for some
types of microbes – if Ganymede’s ocean lacks this key ingredient, it may be sterile,
but the jury is still out.
Liquid water-rock contact is expected to exist on another of Jupiter’s moons, however:
Europa.
In the coming years, Juno will visit Europa too, more than once.
Juno’s extended mission will also give it a close-up look at Io, Jupiter’s fiery innermost
moon, a place more volcanically active than anywhere else in the Solar System.
We can expect some stunning imagery, and new science, out of these upcoming flybys.
Observations taken by Juno will complement and set the stage for two upcoming missions
to Jupiter’s moons.
The European Space Agency’s JUICE will launch in 2022, exploring Ganymede, Callisto, and
Europa in more detail.
NASA’s Europa Clipper will follow later in the 2020s.
"Hey, guys, just a moment before we continue...
BE sure to join the Insanecuriosity Channel...
Click on the bell, you will help us to make products of ever-higher quality!"
The Milky Way?
Neither unique nor rare
Astronomers of the Multi Unit Spectroscopic Explorer (MUSE) on ESO’s Very Large Telescope
have observed UGC 10738, a nearby, edge-on Milky Way-like galaxy, and found that it has
distinct thick and thin disks similar to those of our own Milky Way Galaxy.
This suggests, contrary to previous theories, that such structures are not the result of
a rare long-ago collision with a smaller galaxy; they appear to be the product of more peaceful
change.
Basically, observations indicate that the Milky Way’s thin and thick disks didn’t
come about because of a gigantic mash-up, but a sort-of default path of galaxy formation
and evolution.
From these results, astronomers think galaxies with the Milky Way’ particular structures
and properties could be described as the normal ones.
It was thought that the Milky Way’s thin and thick disks formed after a rare violent
merger, and so probably wouldn’t be found in other spiral galaxies.
The present research shows that’s probably wrong, and it evolved naturally without catastrophic
interventions.
This means Milky Way-type galaxies are probably very common.
“It also means we can use existing very detailed observations of the Milky Way as
tools to better analyze much more distant galaxies which, for obvious reasons, we can’t
see as well.”
Astronomers used the MUSE instrument on ESO’s Very Large Telescope to observe UGC 10738,
a spiral galaxy located some 334 million light-years away in the constellation of Ophiuchus.
We know a lot about how the Milky Way formed, but there was always the worry that the Milky
Way is not a typical spiral galaxy.
Now we can see that the Milky Way’s formation is fairly typical of how other disk galaxies
were assembled.
China's Advanced 'Artificial Sun' Fusion Reactor Just Broke a New World Record
China has achieved a new milestone in humanity's experiments to harness the power of the stars.
On 4 June last, the Chinese Academy of Sciences' fusion machine reached 120 million degrees
Celsius and clung onto this for 101 seconds.
Korea held the previous record of 100 million °C for 20 seconds.
The last time EAST (Experimental Advanced Superconducting Tokamak or HT-7U) held onto
a writhing loop of plasma for so long was in 2017, but the temperature only reached
a mere 50 million °C. In 2018, the reactor held gas heated beyond
the 100 million degrees benchmark regarded as crucial for generating power, but could
only sustain the plasma for around 10 seconds.
Now that it's held plasma at eight times the temperature of the Sun's core of 15 million
°C for such a long period, the new record has nudged the world ever slightly closer
to this elusive, yet highly sought-after clean power source.
Fusion power makes use of the reactions that take place deep inside the Sun, squeezing
hydrogen atoms together into larger elements like helium.
Where the Sun relies on gravity to force atoms together, here on Earth we have to resort
to less subtle means, ramping up temperatures in specially built generators to generate
the atom-melding forces.
Researchers estimate that the amount of deuterium - a stable form of hydrogen containing one
proton and one neutron - in one liter of seawater could produce the energy equivalent of 300
liters of gasoline through nuclear fusion.
It takes around 300 scientists and engineers to support and operate the experimental facility
that contains EAST.
This large, donut-shaped metal tube has a series of magnetic coils used to hold superheated
streams of hydrogen plasma zooming around the core.
The challenge is to hold the plasma in place for long enough, in a hot enough inferno,
for fusion to occur.
It needs to be even hotter than the Sun because our star's much stronger gravity helps squeeze
the nuclei together - something we can't replicate here on Earth.
With the theoretical potential to safely produce such vast amounts of energy without greenhouse
gases and barely any radioactive waste, fusion power is considered by some as the holy grail
of clean energy.
.However, at the moment nuclear fusion is not yet a certainty, with a fully functioning
'artificial sun' still likely decades away.
We have yet to even reach the point where a fusion reactor can spit out more energy
than it consumes, but some experts think we're getting close.
Here's who our stellar neighbors are
A catalog published in Astronomy & Astrophysics - compiled taking into account the latest
data collected by the ESA Gaia space mission - lists the main objects within a radius of
30 light years from the Sun: 541 stars, brown dwarfs, and exoplanets distributed on 339
star systems
Who are our neighbors in the Solar System?
To answer, a team of researchers of the French "Centre National de la Recherche Scientifique"
has ideally drawn a sphere with the Sun at the center and a radius of 30 light years,
then a volume of just over one hundred thousand cubic light years.
And consulting the astronomical catalogs has compiled a list of all major objects in it.
Result: 373 stars (including twenty white dwarfs), about ninety brown dwarfs, and about
eighty extrasolar planets.
For a total of 541 objects distributed in 339 star systems - many of them with two or
more stars.
The new list, described in an upcoming article in Astronomy & Astrophysics, in addition to
the data already present in the literature also takes into account - for about two-thirds
of the stars - the high-precision photometric and astrometric measurements provided by the
recent Gaia Early Data Release 3.
A complete census of known objects within a 10-parsec radius, then, in which parameters
such as spectral class and radial velocity of the stars are also included, as well as
a list of references to facilitate future studies.
This sample represents a cardinal point for many areas of stellar and galactic research.
Indeed, at the lowest level, any proposed model or process must be able to describe
the local population.
With its 541 objects, the catalog highlights the richness and variety of our "solar neighborhood"
- populated by stars of very different types, mass, size, temperature, and age.
These objects are mostly stars - mostly red dwarfs (61 percent), the most common type
of star in the Milky Way - but also, in surprising numbers, brown dwarfs and exoplanets.
This updated census also shows that 28 percent are multiple systems, made up of more than
one object.
Because of their proximity, and therefore the possibility of precise observations, the
stars closest to us provide a unique laboratory for understanding stellar and galactic physics.
Finally, the study considers how the list might evolve as large space and ground-based
telescopes of the future become operational.
Between reality and science fiction, the exoplanetary systems closest to the Sun will be the highest-profile
targets for searching with future instruments for biomarkers in their atmospheres, and they
may one day become the first destinations of future human interstellar travel.
OK guys, we’re done for the week too.
What do you think?
What news struck you the most?