Astronomers have now learned to think in terms  of globality, and to consider more and more our  
Astronomers have now learned to think in terms  of globality, and to consider more and more our  

corner of the galaxy as a set of objects  continuously interacting with each other. 
corner of the galaxy as a set of objects  continuously interacting with each other. 

It is no longer science fiction to claim  that our solar system can be continuously  
It is no longer science fiction to claim  that our solar system can be continuously  

crossed by celestial bodies from  planetary systems outside ours. 
crossed by celestial bodies from  planetary systems outside ours. 

And we had proof with the fascinating cosmic  odyssey that just over three years ago  
And we had proof with the fascinating cosmic  odyssey that just over three years ago  

gave us the fast transit of Oumuamua. 
gave us the fast transit of Oumuamua. 

By now that sort of ghost ship is already near  the orbit of Neptune, 4.3 billion kilometers away,  
By now that sort of ghost ship is already near  the orbit of Neptune, 4.3 billion kilometers away,  

and if we wanted to send him a greeting we  should raise our heads towards the large  
and if we wanted to send him a greeting we  should raise our heads towards the large  

square of the constellation of Pegasus,  within which lies its vanishing point. 
square of the constellation of Pegasus,  within which lies its vanishing point. 

Unreachable, mysterious... Or maybe not?
Unreachable, mysterious... Or maybe not?

After all, we expected this. With the  abundance of planetary systems in our Galaxy,  
After all, we expected this. With the  abundance of planetary systems in our Galaxy,  

it is almost inevitable that an object escaped  from one of them can pass by the Sun. And indeed,  
it is almost inevitable that an object escaped  from one of them can pass by the Sun. And indeed,  

the most shared scenario in the astronomical  community is that the interstellar space  
the most shared scenario in the astronomical  community is that the interstellar space  

is crossed by objects that have been freed from  the gravitational leash of their parent star,  
is crossed by objects that have been freed from  the gravitational leash of their parent star,  

and are freely wandering around waiting to find  another passing star ready to pick them up. 
and are freely wandering around waiting to find  another passing star ready to pick them up. 

The fact is, that on October 19,  2017, astronomer Robert Weryk saw  
The fact is, that on October 19,  2017, astronomer Robert Weryk saw  

(or saw for him the algorithm in charge of  the analysis) that in the images collected  
(or saw for him the algorithm in charge of  the analysis) that in the images collected  

by the Pan-STARSS telescope, placed on top of the  Haleakala volcano on the Hawaiian island of Maui,  
by the Pan-STARSS telescope, placed on top of the  Haleakala volcano on the Hawaiian island of Maui,  

a point object was moving. A first cursory  analysis of the orbit revealed that it had to  
a point object was moving. A first cursory  analysis of the orbit revealed that it had to  

be a comet coming from far beyond the Kuiper belt.  Then, the calculations became more precise, and it  
be a comet coming from far beyond the Kuiper belt.  Then, the calculations became more precise, and it  

came to know that the object had already passed  to perihelion, the point of maximum proximity to  
came to know that the object had already passed  to perihelion, the point of maximum proximity to  

the Sun, on September 9, 2017, at a distance of 38  million kilometers; and that on October 14, four  
the Sun, on September 9, 2017, at a distance of 38  million kilometers; and that on October 14, four  

days before being discovered, it had approached  the Earth up to about 24 million kilometers. 
days before being discovered, it had approached  the Earth up to about 24 million kilometers. 

The presumed comet had therefore already passed  perihelion and was already rapidly receding... 
The presumed comet had therefore already passed  perihelion and was already rapidly receding... 

With the increase of observational data,  its calculated orbit became less and less  
With the increase of observational data,  its calculated orbit became less and less  

approximate and it was possible to determine  that a couple of months before the object was  
approximate and it was possible to determine  that a couple of months before the object was  

approaching the Sun with a very high speed, 87  km per second! A speed that an object belonging  
approaching the Sun with a very high speed, 87  km per second! A speed that an object belonging  

to the Solar System could never have reached! Further calculations led to understand that  
to the Solar System could never have reached! Further calculations led to understand that  

in fact, the object was following a hyperbolic  orbit; not closed like the elliptical orbit that  
in fact, the object was following a hyperbolic  orbit; not closed like the elliptical orbit that  

comets follow, but open... A clear indication that  whatever its nature was, that object had to come  
comets follow, but open... A clear indication that  whatever its nature was, that object had to come  

from outside our system, and not from inside! Such a high speed also meant that the Sun's  
from outside our system, and not from inside! Such a high speed also meant that the Sun's  

gravity could not have slowed down the  object enough to keep it bound to itself,  
gravity could not have slowed down the  object enough to keep it bound to itself,  

and therefore the hypothetical comet after having  circled around the Sun was destined to exit the  
and therefore the hypothetical comet after having  circled around the Sun was destined to exit the  

solar system with the same speed with which  it had entered; only in a different direction. 
solar system with the same speed with which  it had entered; only in a different direction. 

And the astronomers declared themselves so sure  of this to give to the interstellar visitor a name  
And the astronomers declared themselves so sure  of this to give to the interstellar visitor a name  

able to underline its origin. They called  it 'Oumuamua, which in the Hawaiian language  
able to underline its origin. They called  it 'Oumuamua, which in the Hawaiian language  

means "The first messenger from afar". From far away, yes, but from where exactly?  
means "The first messenger from afar". From far away, yes, but from where exactly?  

The only sure thing was that his radiant was  located in the direction of the constellation  
The only sure thing was that his radiant was  located in the direction of the constellation  

Lyra. It came from there, but it is obviously  impossible to find out which was its mother star.
Lyra. It came from there, but it is obviously  impossible to find out which was its mother star.

The intense observing campaign, dictated by the  need to quickly acquire any information about the  
The intense observing campaign, dictated by the  need to quickly acquire any information about the  

visitor before its high speed pushed it too far  away, soon brought to light an unexpected fact:  
visitor before its high speed pushed it too far  away, soon brought to light an unexpected fact:  

it was not a comet! In fact, there was no  way to detect a leakage of gaseous material  
it was not a comet! In fact, there was no  way to detect a leakage of gaseous material  

or dust in the surroundings of the object.  And at that distance from the Sun, just a  
or dust in the surroundings of the object.  And at that distance from the Sun, just a  

few tens of millions of kilometers, the canopy of  a cometary nucleus should have manifested itself. 
few tens of millions of kilometers, the canopy of  a cometary nucleus should have manifested itself. 

In terms of composition as well,  observations suggested that Oumuamua  
In terms of composition as well,  observations suggested that Oumuamua  

looked quite similar to many  asteroids found in our solar system:  
looked quite similar to many  asteroids found in our solar system:  

dense, perhaps rocky, or even metallic. With a  somewhat reddish surface due to long exposure  
dense, perhaps rocky, or even metallic. With a  somewhat reddish surface due to long exposure  

to cosmic rays, a sign that the journey of this  stellar explorer must have lasted millions and  
to cosmic rays, a sign that the journey of this  stellar explorer must have lasted millions and  

millions of years by now So there was no doubt,  
millions of years by now So there was no doubt,  

it had to be an asteroid and not a comet! But the surprises were destined to continue…
it had to be an asteroid and not a comet! But the surprises were destined to continue…

"Hey, guys, just a moment before we continue...  BE sure to join the Insane Curiosity Channel...  
"Hey, guys, just a moment before we continue...  BE sure to join the Insane Curiosity Channel...  

Click on the bell, you will help us to  make products of ever-higher quality!"
Click on the bell, you will help us to  make products of ever-higher quality!"

Its light curve, that is the  variation of brightness over time,  
Its light curve, that is the  variation of brightness over time,  

indicated a gap of six times between the  maximum and minimum and also suggested that  
indicated a gap of six times between the  maximum and minimum and also suggested that  

the object must rotate on itself every 7 hours.  To justify the strong variability we could also  
the object must rotate on itself every 7 hours.  To justify the strong variability we could also  

hypothesize the presence on the surface of the  asteroid of areas of different reflectivity,  
hypothesize the presence on the surface of the  asteroid of areas of different reflectivity,  

but almost immediately it seemed more reliable  to interpret it as the direct consequence  
but almost immediately it seemed more reliable  to interpret it as the direct consequence  

of an extremely elongated shape, with the major  axis a dozen times larger than the minor one. 
of an extremely elongated shape, with the major  axis a dozen times larger than the minor one. 

Although it has never been able to precisely  define its size, the few observations available  
Although it has never been able to precisely  define its size, the few observations available  

indicated a length of about 400 meters and a  width of 40 meters. Nothing like this had ever  
indicated a length of about 400 meters and a  width of 40 meters. Nothing like this had ever  

been observed. Suffice it to say that the most  elongated objects found in our solar system show  
been observed. Suffice it to say that the most  elongated objects found in our solar system show  

a length-to-width ratio never greater than 3! There was a further oddity in Oumuamua...  
a length-to-width ratio never greater than 3! There was a further oddity in Oumuamua...  

it did not show signs of cometary activity, but  nevertheless in its orbital motion was measured  
it did not show signs of cometary activity, but  nevertheless in its orbital motion was measured  

an additional acceleration, not due to the  gravitational attraction of the Sun. The object  
an additional acceleration, not due to the  gravitational attraction of the Sun. The object  

behaved like a comet that accelerates under  the thrust of gaseous jets triggered by solar  
behaved like a comet that accelerates under  the thrust of gaseous jets triggered by solar  

heat. But no comet had ever undergone a similar  acceleration during a close passage to the Sun,  
heat. But no comet had ever undergone a similar  acceleration during a close passage to the Sun,  

and moreover, the gas emissions  would have modified its rotation,  
and moreover, the gas emissions  would have modified its rotation,  

which did not seem to happen. So what could Oumuamua be?  
which did not seem to happen. So what could Oumuamua be?  

A comet or an asteroid? Or what else? To know more would have been necessary to  
A comet or an asteroid? Or what else? To know more would have been necessary to  

make more detections, but by the end of December  2018, the visitor had already passed the orbit  
make more detections, but by the end of December  2018, the visitor had already passed the orbit  

of Saturn and had therefore become too faint to  allow astronomers to continue observing it...
of Saturn and had therefore become too faint to  allow astronomers to continue observing it...

Nearly five years after its discovery, even to  this day, the appearance of Oumuamua continues  
Nearly five years after its discovery, even to  this day, the appearance of Oumuamua continues  

to raise more questions than answers. The  only thing that has become clear is that  
to raise more questions than answers. The  only thing that has become clear is that  

Oumuamua is not an asteroid or comet, or at  least not similar to the asteroids and comets  
Oumuamua is not an asteroid or comet, or at  least not similar to the asteroids and comets  

we know. And most importantly, its origin  is to be found outside of our solar system. 
we know. And most importantly, its origin  is to be found outside of our solar system. 

Some scientists, led by Harvard astronomer  Avi Loeb, even believe that it may be an  
Some scientists, led by Harvard astronomer  Avi Loeb, even believe that it may be an  

artificial object. In recent years many  teams of researchers have tried to explain,  
artificial object. In recent years many  teams of researchers have tried to explain,  

for example, the extraordinary reflectivity of the  object, much higher than that of any known rock,  
for example, the extraordinary reflectivity of the  object, much higher than that of any known rock,  

similar, as the same Loeb came to  say, "to that of polished metal". 
similar, as the same Loeb came to  say, "to that of polished metal". 

What could Oumuamua be made of to reflect  sunlight like that? And again: how to explain  
What could Oumuamua be made of to reflect  sunlight like that? And again: how to explain  

its very strange shape and the non-gravitational  acceleration shown after passing perihelion? 
its very strange shape and the non-gravitational  acceleration shown after passing perihelion? 

Avi Loeb embraces without any  hesitation the idea that this  
Avi Loeb embraces without any  hesitation the idea that this  

object is a sort of highly evolved  alien laser sail. And he supports in  
object is a sort of highly evolved  alien laser sail. And he supports in  

substance that it is a probe driven by the  propulsive radiation of the same starlight,  
substance that it is a probe driven by the  propulsive radiation of the same starlight,  

created by the ingenuity of an extraterrestrial  civilization more advanced than ours. 
created by the ingenuity of an extraterrestrial  civilization more advanced than ours. 

So it is not surprising that in the face of a  mystery so dense and engaging, already shortly  
So it is not surprising that in the face of a  mystery so dense and engaging, already shortly  

after the discovery of Oumuamua someone began to  consider the need to "go and see". Not in person,  
after the discovery of Oumuamua someone began to  consider the need to "go and see". Not in person,  

of course, but by sending a probe. But would it really be possible to  
of course, but by sending a probe. But would it really be possible to  

reach Oumuamua for a possible close-up study?  The members of the Lyra project, funded by the  
reach Oumuamua for a possible close-up study?  The members of the Lyra project, funded by the  

organization Initiative for Interstellar Studies  say yes and are working on some proposals for  
organization Initiative for Interstellar Studies  say yes and are working on some proposals for  

missions with a very specific goal, namely to  investigate closely the interstellar object. 
missions with a very specific goal, namely to  investigate closely the interstellar object. 

But how will we be able to do it given the crazy  speed at which Oumuamua is traveling at this time,  
But how will we be able to do it given the crazy  speed at which Oumuamua is traveling at this time,  

about 27 km / s compared to the Sun, when  the fastest probes ever made (Voyager 1 and  
about 27 km / s compared to the Sun, when  the fastest probes ever made (Voyager 1 and  

2) are traveling at about 17 km per second? The idea is to chase it using the current  
2) are traveling at about 17 km per second? The idea is to chase it using the current  

chemical propulsion at its maximum potential (but  we do not exclude nuclear propulsion and the use  
chemical propulsion at its maximum potential (but  we do not exclude nuclear propulsion and the use  

of laser sails) and one gravity assist with  Jupiter using the so-called Oberth maneuver. 
of laser sails) and one gravity assist with  Jupiter using the so-called Oberth maneuver. 

The latter is done by launching a probe towards  a celestial body as massive as possible,  
The latter is done by launching a probe towards  a celestial body as massive as possible,  

making it acquire more and more speed. Until at  the right time the ignition of the engines will be  
making it acquire more and more speed. Until at  the right time the ignition of the engines will be  

able to give a further boost, which will be added  to the speed due to gravitational attraction. 
able to give a further boost, which will be added  to the speed due to gravitational attraction. 

The ideal would be to use the mass of the  Sun, but apparently, the thing would present  
The ideal would be to use the mass of the  Sun, but apparently, the thing would present  

insurmountable difficulties because of the  intense heat that the probe should bear. 
insurmountable difficulties because of the  intense heat that the probe should bear. 

Researchers have proposed to use  in alternative the mass of Jupiter,  
Researchers have proposed to use  in alternative the mass of Jupiter,  

using previously gravitational  assist with Venus and Earth. 
using previously gravitational  assist with Venus and Earth. 

The maneuver would allow exploiting the  gravitational assist of the gas giant,  
The maneuver would allow exploiting the  gravitational assist of the gas giant,  

which would provide an "escape" at  high speed with very little fuel. 
which would provide an "escape" at  high speed with very little fuel. 

Thus, taking advantage of a 2028 launch window,  the spacecraft could reach Oumuamua in 2050.  
Thus, taking advantage of a 2028 launch window,  the spacecraft could reach Oumuamua in 2050.  

Once reached the object, the spacecraft would  perform a rendezvous and perform a close analysis  
Once reached the object, the spacecraft would  perform a rendezvous and perform a close analysis  

collecting data of immeasurable value. Obviously, we are talking about a very  
collecting data of immeasurable value. Obviously, we are talking about a very  

complex mission and a high risk of failure.  And even if you could develop in time a highly  
complex mission and a high risk of failure.  And even if you could develop in time a highly  

efficient probe, the costs could be exorbitant.  Who will finance such an operation? For now,  
efficient probe, the costs could be exorbitant.  Who will finance such an operation? For now,  

there are no concrete plans yet, nor  funding announcements from any space agency. 
there are no concrete plans yet, nor  funding announcements from any space agency. 

If the project will not be followed within  this year we will probably have to give up  
If the project will not be followed within  this year we will probably have to give up  

the idea of being able to unveil the  many secrets of Oumuamua, and we will  
the idea of being able to unveil the  many secrets of Oumuamua, and we will  

have to wait patiently for another visitor... But maybe we won't have to wait long... just in  
have to wait patiently for another visitor... But maybe we won't have to wait long... just in  

these days, a third possibility has  suddenly materialized... the possibility  
these days, a third possibility has  suddenly materialized... the possibility  

of having an interstellar visitor as  a permanent guest of our solar system!
of having an interstellar visitor as  a permanent guest of our solar system!

A study, published in Monthly Notices  of the Royal Astronomical Society,  
A study, published in Monthly Notices  of the Royal Astronomical Society,  

has in fact reported the discovery of an asteroid  3 km in diameter that revolves around the Sun  
has in fact reported the discovery of an asteroid  3 km in diameter that revolves around the Sun  

sharing the same orbit as Jupiter. No, it is not  one of the many Trojan asteroids trapped in the  
sharing the same orbit as Jupiter. No, it is not  one of the many Trojan asteroids trapped in the  

Lagrangian points of Jupiter, but an object  that moves on its own with the same period of  
Lagrangian points of Jupiter, but an object  that moves on its own with the same period of  

the gas giant. With a great, great peculiarity:  to turn around the Sun with retrograde motion! 
the gas giant. With a great, great peculiarity:  to turn around the Sun with retrograde motion! 

This brings it in the unpleasant situation of  having to dodge the gas giant every time it meets  
This brings it in the unpleasant situation of  having to dodge the gas giant every time it meets  

it along its orbit! Fortunately, gravitational  forces have been making sure for millions of  
it along its orbit! Fortunately, gravitational  forces have been making sure for millions of  

years that the final collision never happens. In fact, the asteroid moves slightly every time  
years that the final collision never happens. In fact, the asteroid moves slightly every time  

it crosses the giant, alternating the gap so that  it passes once inside and once outside its orbit. 
it crosses the giant, alternating the gap so that  it passes once inside and once outside its orbit. 

Bee-Zed (this is the nickname of the  object, used by astronomers instead of an  
Bee-Zed (this is the nickname of the  object, used by astronomers instead of an  

unpronounceable Hawaiian name) is the first  and only asteroid to have this peculiarity. 
unpronounceable Hawaiian name) is the first  and only asteroid to have this peculiarity. 

All planets in our solar system, and most  other objects (except some comets, some minor  
All planets in our solar system, and most  other objects (except some comets, some minor  

satellites, and the great Triton), travel around  the Sun in the same direction: counterclockwise,  
satellites, and the great Triton), travel around  the Sun in the same direction: counterclockwise,  

if observed from the north pole of the ecliptic. If Bee-Zed was born in our system, it should  
if observed from the north pole of the ecliptic. If Bee-Zed was born in our system, it should  

have orbited in the same direction as all other  planets and asteroids, the one inherited from  
have orbited in the same direction as all other  planets and asteroids, the one inherited from  

the movement of the cloud of gas and dust from  which they were formed. But so, it is not. How so? 
the movement of the cloud of gas and dust from  which they were formed. But so, it is not. How so? 

With the support of a long series of simulations,  astronomers are now inclined to think that  
With the support of a long series of simulations,  astronomers are now inclined to think that  

Bee-Zed has been steadily retrograde for billions  of years and that its condition should not be  
Bee-Zed has been steadily retrograde for billions  of years and that its condition should not be  

considered the consequence of some fortuitous  billiard shot. Which seems to lay heavily  
considered the consequence of some fortuitous  billiard shot. Which seems to lay heavily  

in favor of its interstellar origin. According to the authors,  
in favor of its interstellar origin. According to the authors,  

the exchange of asteroids between the Sun  and other planetary systems was facilitated  
the exchange of asteroids between the Sun  and other planetary systems was facilitated  

by the fact that 4.5 billion years ago the Sun  must have formed together with other stars,  
by the fact that 4.5 billion years ago the Sun  must have formed together with other stars,  

very close to each other. This allowed  asteroids, comets (and perhaps larger objects,  
very close to each other. This allowed  asteroids, comets (and perhaps larger objects,  

such as Triton) to fill interstellar space and  be attracted to stars other than their own.
such as Triton) to fill interstellar space and  be attracted to stars other than their own.

In short, we had an interstellar visitor  "in the house" and didn't know it! 
In short, we had an interstellar visitor  "in the house" and didn't know it! 

Sure, maybe not an object with the  suggestive characteristics shown by Oumuamua,  
Sure, maybe not an object with the  suggestive characteristics shown by Oumuamua,  

but still an object that came "from outside". No? And at this point, the question can only be this:  
but still an object that came "from outside". No? And at this point, the question can only be this:  

what are we waiting for? 
what are we waiting for? 

Bee-Zed seems in fact an asteroid quite  easy to reach. Why not go and have a look?
Bee-Zed seems in fact an asteroid quite  easy to reach. Why not go and have a look?