space is vast seemingly endless and much beyond the reach of humanity but perhaps it is still not
big enough to overshadow the imagination and curiosity of humans Albert Einstein once said
the mind that opens to a new idea never returns to its original size
thanks to curiosity we have found more than 4 000 exoplanets in the milky way in the last
couple of decades and this number will keep on growing because the galaxy has billions of stars
and we are not going to stop looking for more potential super earths
possibly extraterrestrial life weird and amazing giant planets and lone wanderers
science unanswered questions and bragging rights are taking astronomers beyond the milky way galaxy
as we strive to find other planets that support life now let's stop wasting time and just dive
right in NASA's Chandra x-ray observatory has opened up a window that has a vista far
beyond the horizons of our own galaxy thanks to this observation we may have already found
signs of a planet transitioning a star outside of the milky way galaxy welcome to fact nominal
and today let's talk about the probable extra galactic exoplanet nasa may have just discovered
nearly 30 million light years from our planet lies the whirlpool galaxy just southeast of the big
dipper this galaxy can be seen in the northern constellation kens venatici properly known as
m51 or ngc 5194 the galaxy is sort of a super model of space as it is known for
being the brightest and the most photogenic galaxy that we can see the reason behind its
shine and glamour is the abundance of supernovas that we have recorded there in recent years the
whirlpool galaxy is sort of considered astronomy's galactic darling for how much it has to offer us
and now it is offered something so phenomenal that could change our perception of extragalactic space
for the first time in history scientists may have just discovered a planet in another galaxy
yes you heard that right folks surprise few decades ago crossing the threshold of our
solar system was a dream and now we are peering outside of our galaxy as captain picardman said
things are only impossible until they're not yes sir currently named m51 uls-1b which is
a mouthful to remember the exoplanet is going to be the first of many we may discover soon in this
amazing galaxy we may even have to come up with a new term for these extra galactic exoplanets
exoplanets are defined as planets outside of our solar system and until now all exoplanets that
we found inside happen to be native to the milky way but not from our solar system this discovery
is a game changer as m51uls1b is located not even outside our solar system but millions of light
years away from our galaxy as well such discovery opens up a whole new arena for finding other
worlds come on elon we need your help maybe spacex and nasa will collaborate on future endeavors
x-ray wavelengths have increased our horizons for searching new exoplanets beyond the boundary
of our own galaxy this new method is based on transits that are events in which the passage of
a planet in front of a star blocks some of the star's life and produces a characteristic dip
it is similar to astronomers using both ground-based and space-based telescopes
such as nasa's kepler and tess missions that were extremely successful in finding dips in optical
light and electromagnetic radiation humans cannot see enabling the discovery of thousands of planets
so what's different in this new technology roseanne de stefano of the center for astrophysics
at harvard and smithsonian in cambridge massachusetts led a team that looked for
dips in the brightness of x-rays received from x-ray bright binaries instead of optic sources
these luminous systems typically contain a neutron star or black hole pulling in gas from a closely
orbiting companion star the material near the neutron star or a black hole becomes superheated
and glows in x-rays the region producing bright x-rays is very small so if a planet passes in
front of it it would block the majority if not all of the x-rays that makes the transit quite easier
to detect as the x-rays would completely disappear and that is why this method is very effective to
discover exoplanets at massive distances which is impossible with the optical light transit method
and that is precisely how dr destefano's team detected an exoplanet candidate in a binary system
called m51uls1 located in m51 this binary system contains a black hole or neutron star
orbiting a companion star with a mass about 20 times that of the sun
the x-ray transit they found using chandra data lasted about three hours
during which the x-ray emission decreased to zero based on this and other information the
researchers estimate the exoplanet candidate in m51 uls-1 would be roughly the size of saturn
and orbit the neutron star or black hole at about twice the distance of saturn from the sun
however we shouldn't get our hopes too high without collecting more data to verify that
what we are looking at is indeed an extra galactic exoplanet one of the major hurdles
to get back studying this probable planet is its enormous orbit and it would not cross
in front of its binary partner again for about 70 years that means unless we can come up with
another way to confirm its existence we have to wait for decades and that's not the worst part
the worst part is that even after waiting for decades we can't be sure when to look for it we
only have an estimate about its orbit and there's a chance we are not looking at a planet at all
there is a fairly good chance that the dimming could have been caused by a cloud of gas and dust
passing in front of the x-ray source and not a planet however the research team strongly
disagrees they argue that the characteristics of the event observed in m51 uls-1 are not consistent
with the passage of such a cloud but they are consistent with the model of a planet candidate
still claiming that it's an extra galactic exoplanet is a bold claim
despite being an exciting one this is why the claim needs to be carefully reviewed by
astronomers even though the argument in favor of this spot being a planet is very strong
this is a binary system of a neutron star and companion star we're talking about
such a binary system won't be easy for planets to survive even at the distance of this planet
this planet likely had a tumultuous history and violent past an exoplanet in the system
would have had to survive a supernova explosion that created the neutron star or black hole even
the future in this scenario would be extremely bleak at some point the companion star could
also explode as a supernova and blast the planet once again with extremely high levels of radiation
using both chandra and the european space agency's xmm-newton the research team has looked for x-ray
transits in three galaxies beyond our own they searched a total of 55 systems in m51 64 systems
in messier 101 also known as the pinwheel galaxy and a total of 119 systems in the messier 104
fondly called sombrero galaxy for its unusual shape it is not very exciting to say this but
quite extensive research resulted in the discovery of just this one extra galactic
exoplanet candidate but hopefully this is just the beginning the researchers are still searching the
archives of both chandra and xmm newton for more exoplanet candidates in other galaxies
substantial chandra datasets are available for at least 20 galaxies including some like m31
and m33 that are much closer than m51 so hopefully that will allow shorter transits to be detectable
another interesting line of research could be to search for x-ray transits in milky way
x-ray sources to discover new nearby planets in unusual environments that would be an interesting
discovery and a new branch of exoplanets tell us in the comments how you think planets of different
galaxies will be different from each other and as always thanks for watching Factnomenal
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