Atlas, a massive comet five times the size of Jupiter and about half the size of the Sun, will appear brighter than Venus from Earth by the end of April.
The exact size of the rocky icy core of the strange comet isn't known but is likely only a few miles across - but it has a much larger atmosphere.
It's currently close to Mars' orbit but is increasing in speed as it makes its way towards the Sun and will make its closest approach to Earth in April.
When it gets towards the inner solar system it will become one of the brightest objects in the night sky and potentially the 'comet of a generation'.
Discovered last year in December, is on its way towards Earth and could appear as bright as a crescent moon – unless it explodes from the Sun’s heat.
Atlas is currently close to Mars’ orbit and is increasing its speed as it makes its way towards
the Sun. It will be at the closest distance to Earth at the end of May.
the Sun. It will be at the closest distance to Earth at the end of May.
The comet was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in
Hawaii and was named from the initials of the system. It is officially called C/2019 Y4
Hawaii and was named from the initials of the system. It is officially called C/2019 Y4
Seeing a comet with the naked eye is the rarest event -the last bright comet visible without a
telescope in the northern hemisphere was Hale-Bopp in 1997.
telescope in the northern hemisphere was Hale-Bopp in 1997.
When it was discovered on December 28, 2019, it was faint and required a telescope, but as
it comes closer it is getting brighter and can now be seen with binoculars.
it comes closer it is getting brighter and can now be seen with binoculars.
It’s glow will be amplified by the Sun the closer it gets to the star and is becoming brighter
faster than astronomers expected.
faster than astronomers expected.
‘Comet ATLAS continues to brighten much faster than expected,’ Karl Battams of the Naval
Research Lab in Washington DC told to Space Weather Archive.
Research Lab in Washington DC told to Space Weather Archive.
‘Some predictions for its peak brightness now border on the absurd.
It has seen a 4,000-fold increase in brightness since it was first discovered and could be
clearly seen from the naked eye as early as April.
clearly seen from the naked eye as early as April.
When it was originally spotted, the comet was in Ursa Major and appeared 398,000 times
dimmer than stars that are visible to the naked eye from Earth.
dimmer than stars that are visible to the naked eye from Earth.
Unfortunately, there is a real chance it will break up from the heat before it gets a chance to
put on a show for astronomers.
put on a show for astronomers.
‘Right now the comet is releasing huge amounts of its frozen volatiles (gases),’ says Battams.
‘That’s why it’s brightening so fast.’
‘That’s why it’s brightening so fast.’
To survive long enough for it to be visible as a bright light in the sky it would need to be able
to hold on to its ice.
to hold on to its ice.
To do this it would have to have a large nucleus with a store of frozen gas – something
astronomers can’t confirm at the moment.
astronomers can’t confirm at the moment.
If it doesn’t have a large nucleus it will likely ‘run out of gas’ leading to it crumbling and fading
as it approaches the Sun, according to SpaceWeatherArchive.
as it approaches the Sun, according to SpaceWeatherArchive.
Battams is not optimistic it will survive, he said it will likely break up.
‘My personal intuition is that Comet ATLAS is over-achieving, and I wouldn’t be surprised to see it start to fade rapidly and possibly even disintegrate before reaching the sun,’ he says.
The head (or coma) of Comet ATLAS is big, albeit ‘very faint and ghostly,’ John Bortle, an
expert in comets told Space.com.
expert in comets told Space.com.
‘If it’s a truly significant visitor, it should be considerably sharper in appearance. Instead, we see, at best, a quite modestly condensed object with only a pinpoint stellar feature near its heart.’
If it does break up as it approaches the Sun it may still be possible for a NASA spacecraft to
capture images of the end of its life.
capture images of the end of its life.
‘The Heliospheric Imager on NASA’s STEREO spacecraft will get a great view of ATLAS frommid-May through early June,’ says Battams.
‘The camera is very sensitive, so we might be able to observe ATLAS’s tail interacting with
the solar wind and outflows–as well as any potential breakup events.’
the solar wind and outflows–as well as any potential breakup events.’
There is some speculation this could be related to the Great Comet of 1844 as it follows a
similar trajectory and orbit.
similar trajectory and orbit.
Its trajectory would require a 6,000-year orbit around the Sun that would take it beyond the outer
edges of the solar system – about 57 billion miles from the Sun.
edges of the solar system – about 57 billion miles from the Sun.
Astronomers predict Atlas and the Great Comet both broke off from a much larger comet born in
the early days of the solar system.
the early days of the solar system.
If it does last until it gets near the Sun it may be a one time shot as it could be expelled from the
solar system completely after slingshotting around the Sun.
solar system completely after slingshotting around the Sun.
In the meantime, when it gets dark it will be visible halfway up in the north-northwest sky and
potentially visible with the naked eye from April.
potentially visible with the naked eye from April.
‘It’s going to be fun the next few weeks watching Comet ATLAS develop (and provide a nice
distraction from the current state of the world), Carl Hergenrother, a comet observer based in
Arizona, wrote. ‘Here’s to good health and clear skies!’
distraction from the current state of the world), Carl Hergenrother, a comet observer based in
Arizona, wrote. ‘Here’s to good health and clear skies!’