BC D E F G H
scienceillustrated.com.au | 33ANALYSES INDICATE A
COMPACT PLANETARY SYSTEM
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The space telescope's observations
showed that the seven Earth-like
planets orbit the dwarf star very
closely. The orbits only take between 1.5 days
for the innermost planet and 19 days for the
most remote one. Three of the planets are
located in the star's habitable zone, where
liquid water could exist.
stabilised their
wild orbits.
The seven rocky
planets orbit the star in
the same plane, and their
orbits are synchronised. As
the innermost planet orbits
the star eight times, the next
three planets take five, three,
and two orbits respectively during
the same period of time.
The seven planets are all located so
close to the star that they are probably
locked by tidal forces, so the same side will
always be facing the dwarf star. The
planets also have warm day sides, where
temperatures can rise above the boiling
point of water, and cold night sides, which
could be completely covered in ice. Under
such conditions, the border regions
between the day sides and the night sides
will offer the best chances of finding life.THE ATMOSPHERE IS IMPORTANT
Together with the previous discovery of a
rocky planet in the habitable zone of the
Solar System’s closest neighbour, thedwarf planet of Proxima Centauri, the
discovery of the seven Earth-like planets
has made astronomers more interested in
red dwarfs. Next year, NASA will launch
the TESS satellite, which is to search for
planets near 10,000 close dwarf stars.
Red dwarfs are the most common stars of
the universe, and in our galaxy, the Milky
Way, they make up 85 % of the stars.
Astrobiologists are currently working
hard to estimate the possibilities of
finding life in small, compact, planetary
systems orbiting faint dwarf stars.
Preliminary investigations have revealed
several factors, which are unfavourable
for life to exist on rocky planets close to
red dwarfs.
Dwarf stars have frequent outbreaks,
by which they eject large quantities of
charged particles into space, such as
protons and electrons. The outbreaks can
be so intense that they cause magnetic
storms, which might be thousands of
times more powerful than the worst
geomagnetic solar storms on Earth. The
radiation will pose a threat to all life forms,
unless the planets are protected byNASA’S NEW SPACE TELESCOPE
TO REVEAL THE LAST DETAILS5
When NASA’s James Webb space telescope is
launched next year, the analysis of the
planets' atmospheres will begin. The method
is spectroscopy, by which the telescope measures the
wavelengths of the light from the star that passes
through a planet's atmosphere. Different molecules
absorb and dim specific wave-lengths of the
light. Based on this, scientists
can tell the substances in
the atmosphere such
as methane, which is
emitted by bacteria.STELLAR SYSTEM