Comet NeoWise

Oneiric 3 · 10-07-2020 11:10pm #1

This is fascinating and something to look out for over the coming weeks:

https://www.youtube.com/watch?v=todMvN-bnEA

According to the narrator (who runs a great channel) the comet should be visible in the northern sky, and best viewed in the late evening or very early morning.

oriel36 · 11-07-2020 7:20am

Oneiric 3 wrote: »

According to the narrator (who runs a great channel) the comet should be visible in the northern sky, and best viewed in the late evening or very early morning.

https://www.youtube.com/watch?v=4AEluR-CBu4

I had been watching that comet since it came into view of the C3 camera but unlike most other comets which dive into the central Sun, this one progressed out of range of the camera and eventually as a dawn appearance to the right of the Sun as it crossed the orbital plane of the Earth.

Now it is both a twilight and dawn appearance which means it is above the central Sun and this is rare for all near planets of the solar system inhabit a region close to the orbital plane of the Earth. It is why Venus and Mercury transition from a twilight to dawn appearance as they move from left to right of the Sun and between the Earth or from a dawn to twilight appearance as they move behind the Sun but never a dawn and twilight appearance simultaneously.

The first annual appearance of the brightest star Sirius to the right of the Sun or a dawn appearance after being lost to the glare of the central Sun for a number of weeks marked a meteorological event that was the flooding by the Nile of the Delta and gives us our modern calendar system -

"On account of the precession of the rising of Sirius by one day in the course of 4 years therefore it shall be, that the year of 360 days and the 5 days added to their end, so one day shall be from this day after every 4 years added to the 5 epagomenae before the New Year" Canopus Decree, 236 BC

M.T. Cranium · 11-07-2020 7:50am

I just posted some info in the astronomy forum, this link is included:

https://skyandtelescope.org/astronomy-news/anticipation-grows-for-comets-neowise-and-lemmon/

otherwise have a look over there for more info. I think Ireland is far enough north that you should be able to view it all night although it will tend to dip close to the northern horizon around 0100-0200h. Further south it sets and then rises again during the night as those observers have the great bulk of my cranium in the way (or is it something to do with the earth, looking into it).

DumbBrunette · 11-07-2020 9:31am

Thanks MT

It's very easy to spot, I went out just after 2am and the comet was clearly visible without binoculars, tail and all. It reminded me of the way Hale Bopp looked a few weeks after its peak.

Throw in Jupiter, Saturn, Mars, the Moon, a red Venus rising, a pass by the ISS and a stunning display of NLC, it really was a class night for astronomy nerds

M.T. Cranium wrote: »

I just posted some info in the astronomy forum, this link is included:

https://skyandtelescope.org/astronomy-news/anticipation-grows-for-comets-neowise-and-lemmon/

otherwise have a look over there for more info. I think Ireland is far enough north that you should be able to view it all night although it will tend to dip close to the northern horizon around 0100-0200h. Further south it sets and then rises again during the night as those observers have the great bulk of my cranium in the way (or is it something to do with the earth, looking into it).

oriel36 · 11-07-2020 9:45am

DumbBrunette wrote: »

Thanks MT

Throw in Jupiter, Saturn, Mars, the Moon, a red Venus rising, a pass by the ISS and a stunning display of NLC, it really was a class night for astronomy nerds

Jupiter and Saturn provide a different perspective to Venus and Mercury as we look towards the outer solar system and the slower moving planets. We are overtaking Jupiter and Saturn at our closest points at the moment as they temporarily fall behind in view(retrograde motion) -

https://apod.nasa.gov/apod/ap011220.html

The comet disrupts the normal predictive nature of that side of astronomy and that is why it was always disconcerting to astronomers throughout history where predictable motions of the planets and moon were upset. It still does today as I see people try to put the comet in perspective.

sryanbruen · 11-07-2020 11:46am

Noctilucent clouds and Neowise at Howth Harbour this morning (can see the comet above the tower). Image is a bit out of focus - may have a better one from the summit which I'll post some other time. Wasn't sure to post this in noctilucent clouds thread or here.

little bess · 11-07-2020 2:06pm

sryanbruen wrote: »

Noctilucent clouds and Neowise at Howth Harbour this morning (can see the comet above the tower). Image is a bit out of focus - may have a better one from the summit which I'll post some other time. Wasn't sure to post this in noctilucent clouds thread or here.

Hi, great photo! Were you using a slow shutter speed here, the tail of the comet looks so visible!?

sryanbruen · 11-07-2020 6:04pm

little bess wrote: »

Hi, great photo! Were you using a slow shutter speed here, the tail of the comet looks so visible!?

Yeah, settings were ISO-100, f/4.0 and 30" with manual focus for interest. No exposure compensation.

Thanks for the compliment.

oriel36 · 13-07-2020 1:31pm

https://theskylive.com/planetarium?objects=sun-moon-c2020f3-mercury-venus-mars-jupiter-saturn-uranus-neptune-pluto&localdata=51.48%7C0%7CGreenwich%2C+United+Kingdom%7CEurope%2FLondon%7C0&obj=c2020f3&h=12&m=15&date=2020-07-13#ra|7.498724925433215|dec|22.945355546999185|fov|50

That is the view of the inner solar system and the position of the comet just outside the glare of the Sun where it is seen largely as a dawn appearance but due to its location above the Sun, it straddles a twilight and dawn appearance. The reason for this is because everything to the right side of the Sun is a dawn appearance while all observations to the left of the Sun is a twilight appearance.

https://www.youtube.com/watch?v=4AEluR-CBu4&t=7s

If weather enthusiasts wish to understand the dynamics behind the seasons, they are going to have to appreciate the change in position of the stars from left to right of the central/stationary Sun in response to the Earth's orbital motion. The North polar latitude is fixed in orientation to Polaris so, by logic, the North pole also turns parallel to the orbital plane as a function of the Earth's orbital motion. It is why there is a single day/night cycle at that location despite a daily rotational velocity of zero.

The location of the comet and its position to the orbital plane of the Earth and to the central Sun is part of the more expansive perspective of the present celestial spectacle, at least those open to interpretative judgments.

pauldry · 13-07-2020 2:02pm

Will this be still there in September when the sky in the Northwest will be free of cloud again.

Only 20hours of sunlight in July so hard to get a cloudless sky.

4068ac1elhodqr · 13-07-2020 2:39pm

Another more curious comet to look out for will show up on Friday 13th April 2029, viewable to 2bn with their naked eyes.

Named after the Egyptian god of 'chaos, ship or chaotic being': Apophis 99942
It'll be the closest of this size, to breeze by in 1,000yrs or so.

It stretches about 1,100 feet (340 meters) across and will pass within 19,000 miles (31,000 kilometers) of Earth's surface.
There is slight concern that the Earth's gravitational pull pull/distort Apophis, during this close approach.
Back in 2004 it was given a small chance 2.7% of an Earth slam, since reduced.

If this risk does increase for some reason, and Trump's new space force seeks to blast it (like the movies),
this will only worsen the risk (more debris risk/scatter, contained within it's own large gravitational pull).
The potential damage from something this size, would be fitting with that known as 'Wormwood'.

oriel36 · 13-07-2020 3:04pm

pauldry wrote: »

Will this be still there in September when the sky in the Northwest will be free of cloud again.

Only 20hours of sunlight in July so hard to get a cloudless sky.

https://theskylive.com/planetarium?objects=sun-moon-c2020f3-mercury-venus-mars-jupiter-saturn-uranus-neptune-pluto&localdata=51.48%7C0%7CGreenwich%2C+United+Kingdom%7CEurope%2FLondon%7C0&obj=c2020f3&h=12&m=15&date=2020-07-13#ra|7.627972144635855|dec|30.161966765777265|fov|56

I adjusted the view to show the comet roughly in relation to orbital plane of the Earth by using Venus and Mercury as a guide for roughly similar orbital planes to the Earth with the central Sun stationary to all our motions. There is a hands-on app which allows observers to work with the perspective that bests suits them especially from a solar system perspective rather than being restricted to the local horizon and daily rotational coordinates of North/South/East/West.

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C%2F2020%20F3;old=0;orb=1;cov=0;log=0;cad=0

It gives a lot of depth perception which should attract the curious by grabbing the central image and arranging it until it satisfies the trajectory of the comet in relation to the motions of the planets by scrolling the dates forwards or backwards.

Everything to the right of the Sun is a dawn appearance while everything the left of the Sun is a twilight appearance so the trajectory of Neowise is towards an evening appearance quite shortly but moving away from the Sun which will therefore eventually diminish the luminosity of the tail. It should be good enough for July but as seen in the C3 camera, it moves pretty rapidly from its position from below to above the Sun a few weeks ago to presently traveling from above the Sun to below the Sun's equatorial plane in the coming weeks in the same rapid motion

https://www.youtube.com/watch?v=4AEluR-CBu4&t=7s

While the narrator of the time lapse picks up on the now familiar change in positions of the background stars and Mercury as it passes between the Earth and the Sun, there is another important event within that sequence. He mentions U Orionus as the comet heads Northwards with this star changing position to the orbital plane in response to the Earth's orbital motion. The comet too is subject to this apparent change from left to right of the stationary Sun but that is also a perspective created by the Earth's own orbital motion.

The point here is that the great star Sirius too is transitioning from an evening to morning appearance or from left to right of the Sun. It was the first annual appearance at dawn which represents the foundations of all timekeeping, at least in our modern era -

"On account of the precession of the rising of Sirius by one day in the course of 4 years therefore it shall be, that the year of 360 days and the 5 days added to their end, so one day shall be from this day after every 4 years added to the 5 epagomenae before the New Year" Canopus Decree, 236 BC

That observation is probably far older than that written expression -

https://arxiv.org/ftp/arxiv/papers/1509/1509.00134.pdf

The comet is a great way for people to consider how our ancestors made use of twilight and dawn appearances and how it finds an expression in heliocentric astronomy and especially cause and effect between the motions of our planet and Earth sciences including meteorology.

SouthWesterly · 13-07-2020 9:45pm

Alicia Scarce Evergreen wrote: »

Another more curious comet to look out for will show up on Friday 13th April 2029, viewable to 2bn with their naked eyes.

Named after the Egyptian god of 'chaos, ship or chaotic being': Apophis 99942
It'll be the closest of this size, to breeze by in 1,000yrs or so.

It stretches about 1,100 feet (340 meters) across and will pass within 19,000 miles (31,000 kilometers) of Earth's surface.
There is slight concern that the Earth's gravitational pull pull/distort Apophis, during this close approach.
Back in 2004 it was given a small chance 2.7% of an Earth slam, since reduced.

If this risk does increase for some reason, and Trump's new space force seeks to blast it (like the movies),
this will only worsen the risk (more debris risk/scatter, contained within it's own large gravitational pull).
The potential damage from something this size, would be fitting with that known as 'Wormwood'.

It will be raining that year

4068ac1elhodqr · 13-07-2020 10:04pm

SouthWesterly wrote: »

It will be raining that year

Ah sure 'Lord of chaos' might burn up any cloud in these parts, at it's closest approach, just before 6 p.m. EDT Fri 13th Apr 2029, Apophis will be over the Atlantic Ocean – and it will move so fast that it will cross the Atlantic in just an hour (West Africa to NE Americas).

It will also cross the width of a typical visable full moon within 60seconds.

It won't be earth destroying should it touch down, but would be double the object size of the 1908 Tunguska event (possibly more than double the impact too, depending on economies of scale and angle of approach (e.g. 45 degree).

Could certainly kick up enough dust for Wormwood's 3days of darkness or throw in a (super-mega) tsunami for the Atlantic, and the 1/4 world population reduction might also be on the cards.

Something of this size is due to slam every 80k yrs or so.

Expect some Sat interference from this badboy (blue dots).

If Musk is having a raffle for free trips to colonise Mars, have a lucky dip.
If you have a full 7mm wetsuit, and head torch, also have that accessible, that afternoon.

SouthWesterly · 14-07-2020 10:05am

Alicia Scarce Evergreen wrote: »

Ah sure 'Lord of chaos' might burn up any cloud in these parts, at it's closest approach, just before 6 p.m. EDT Fri 13th Apr 2029, Apophis will be over the Atlantic Ocean – and it will move so fast that it will cross the Atlantic in just an hour (West Africa to NE Americas).

It will also cross the width of a typical visable full moon within 60seconds.

It won't be earth destroying should it touch down, but would be double the object size of the 1908 Tunguska event (possibly more than double the impact too, depending on economies of scale and angle of approach (e.g. 45 degree).

Could certainly kick up enough dust for Wormwood's 3days of darkness or throw in a (super-mega) tsunami for the Atlantic, and the 1/4 world population reduction might also be on the cards.

Something of this size is due to slam every 80k yrs or so.

Expect some Sat interference from this badboy (blue dots).

If Musk is having a raffle for free trips to colonise Mars, have a lucky dip.
If you have a full 7mm wetsuit, and head torch, also have that accessible, that afternoon.

Im up a mountain, I'll be, grand...

namloc1980 · 14-07-2020 11:46am

Cloudy weather not playing ball, haven't been able to see this yet. Maybe it'll be clear when it comes around again on its orbit in about 7,000 years time.

Calibos · 14-07-2020 8:51pm

Any seasoned amateur astronomer in Ireland will quickly learn that all time limited astronomical events will be clouded out for the entire duration. If its a 5 minute thing, it'll be clouded out for that specific 5 mins. It its an hour thing it'll be clouded out for that hour. One night thing? Cloudy or that night only, week maximum for meteor shower? Cloudy all week. Comet visible for a few weeks?......................Guys, we won't be seeing the sky or Sun till August I am afraid. This comet is a Harbinger of Gloom

M.T. Cranium · 15-07-2020 12:11pm

I just got in from viewing it, best around 0245h local time before much sunrise glow began to overcome it, quite easy to see without binoculars but of course more impressive in the binocs. Would say it is third magnitude about equal to the faintest of the seven primary stars in Ursa Major (which you can see off to the left of the comet for comparison). That "faintest" is only a bit fainter than the rest. My view here is a bit restricted by hills on the northern horizon, without those it would have been quite high above the horizon but where I was just a bit over the flank of the hill (which is 300 metres higher than my elevation here).

Also in view this morning, waning crescent of the Moon between Venus and Mars, both of which are very bright, and of course Jupiter and Saturn setting in the southwest. Aldebaran is quite close to Venus. Looks like a rendezvous with the moon this time tomorrow, might go back out for that.

The comet should make its way into evening sky viewing soon, I haven't got a very good view to the northwest without a long walk. By the 22nd it gets entangled with bright stars in Ursa Major (not in the primary seven but lower down, the bear's legs basically). Before that it is cruising through fairly empty skies with faint stars of the constellation Lynx which I could only see in binoculars even in near darkness. Those are closer to fifth magnitude anyway, by the time you find those you'd have seen the comet (the tail was quite easily seen naked eye too, at least the portion within a lunar diameter of the nucleus, a longer tail emerges through binoculars).

Not sure how many more days of decent viewing are left before it gets too far from the Sun to produce the goods, might be only 3-4 days left before the inevitable fade-out begins.

pauldry · 15-07-2020 12:32pm

If a miraculous clear slot appears in Ireland tonight what is the best time exactly to see this?

I am sure it is already written in the previous replies but I cant see it.

As in when and where do I stare at the sky in case its like now with smidgeons of blue or clear sky

sryanbruen · 15-07-2020 12:59pm

sryanbruen wrote: »

Image is a bit out of focus - may have a better one from the summit which I'll post some other time.

Here is that image I speak of from last Saturday morning.

Oneiric 3 · 15-07-2020 7:29pm

M.T. Cranium wrote: »

Not sure how many more days of decent viewing are left before it gets too far from the Sun to produce the goods, might be only 3-4 days left before the inevitable fade-out begins.

According to that video posted in the original post (if I remember correctly) July 23rd is when the comet shall be closest to the earth.

lolie · 15-07-2020 8:29pm

pauldry wrote: »

If a miraculous clear slot appears in Ireland tonight what is the best time exactly to see this?

I am sure it is already written in the previous replies but I cant see it.

As in when and where do I stare at the sky in case its like now with smidgeons of blue or clear sky

Looking at Sat24 you might just need a miracle.
Look North nortwest around midnight and further to the Northeast after that.
Download a night sky app like Stellarium or similar to help find it.
Should be easy to spot IF skies clear.

SouthWesterly · 15-07-2020 8:31pm

This might help

M.T. Cranium · 15-07-2020 8:33pm

True (comet closest to earth July 23) and that should be one positive component in maintaining visibility, but increased separation from the Sun will be working in the other direction. So it may flat-line from now to then and afterwards drop off rapidly after 23rd. Once it goes below fourth magnitude you will need binoculars to find it.

For those asking where to look, at 0200-0300h before dawn glow is too bright, try this ... once you're in a good dark place with a fairly unobstructed view north through east, locate Venus (very bright) rising with a noticeable red star beside it (Aldebaran). If tonight, you'll see the crescent of the moon in that area too. Then look off to the left (more northeast), find two stars, one fairly bright (Capella) and one about half as bright, pointing down and to the left.

Then look well to the left and find the familiar seven stars of the Big Dipper, or Plough, which will be oriented with the bowl pointing upwards, handle off to the left. Note the star which is at the intersection of handle and bowl, that one is somewhat less bright than the other six (it is third magnitude, the others closer to second). That somewhat dimmer star of the seven is very similar in magntiude to the comet's nucleus (as of last night in my view of it).

Now you should be able to spot the comet, it's going to be halfway between those two gujde stars and the bowl of the Big Dipper. It will be the only star comparable to the Big Dipper stars in that rather wide expanse of sky. If you have really dark skies, you may notice five or six fainter stars in an uneven line at roughly equal intervals. That is part of the constellation Lynx and the comet is currently moving right to left (west) below that pattern. By tonight it should have reached the mid-way point.

You should then see that it's the comet in that star-less void with a faint tail extending up and slightly to the left.

Also if you're out at that time, look in the opposite direction and find Jupiter and Saturn setting in the southwest, and then Mars quite bright and rising higher than Venus in the southeast.

SouthWesterly · 15-07-2020 9:41pm

M.T. Cranium wrote: »

True (comet closest to earth July 23) and that should be one positive component in maintaining visibility, but increased separation from the Sun will be working in the other direction. So it may flat-line from now to then and afterwards drop off rapidly after 23rd. Once it goes below fourth magnitude you will need binoculars to find it.

For those asking where to look, at 0200-0300h before dawn glow is too bright, try this ... once you're in a good dark place with a fairly unobstructed view north through east, locate Venus (very bright) rising with a noticeable red star beside it (Aldebaran). If tonight, you'll see the crescent of the moon in that area too. Then look off to the left (more northeast), find two stars, one fairly bright (Capella) and one about half as bright, pointing down and to the left.

Then look well to the left and find the familiar seven stars of the Big Dipper, or Plough, which will be oriented with the bowl pointing upwards, handle off to the left. Note the star which is at the intersection of handle and bowl, that one is somewhat less bright than the other six (it is third magnitude, the others closer to second). That somewhat dimmer star of the seven is very similar in magntiude to the comet's nucleus (as of last night in my view of it).

Now you should be able to spot the comet, it's going to be halfway between those two gujde stars and the bowl of the Big Dipper. It will be the only star comparable to the Big Dipper stars in that rather wide expanse of sky. If you have really dark skies, you may notice five or six fainter stars in an uneven line at roughly equal intervals. That is part of the constellation Lynx and the comet is currently moving right to left (west) below that pattern. By tonight it should have reached the mid-way point.

You should then see that it's the comet in that star-less void with a faint tail extending up and slightly to the left.

Also if you're out at that time, look in the opposite direction and find Jupiter and Saturn setting in the southwest, and then Mars quite bright and rising higher than Venus in the southeast.

Thanks, MT. But I can't see past my front gate with low cloud.

Oneiric 3 · 15-07-2020 9:49pm

M.T. Cranium wrote: »

it's going to be halfway between those two gujde stars and the bowl of the Big Dipper

We call it 'The Plough' around these ole' honky tonk parts.

jogdish · 15-07-2020 10:14pm

more clouds (west), dark skies tells me Friday/Saturday and Saturday/Sunday nights look promising.

M.T. Cranium · 16-07-2020 7:38am

Now it's quite easy to find in the late evening too, I think it got a bit brighter in the past 21 hours having just seen it to my NNW. Basically for evening viewing, my earlier guide won't totally work because the guide stars in Auriga (Capella and mate) are not above the horizon and the whole panorama is tilted around, you have to start from the Big Dipper (Ursa Major) and work down to the right from its bowl towards the northern horizon (not sure how to word that for Plough, you get the idea anyway). You should find the comet along that path and it's considerably brighter than anything between the Big Dipper's bowl and the horizon.

By 0100h it would be due north with tail pointing straight up, and at 0300h follow the info I posted yesterday.

Quite a sight in binoculars, somewhat faint to naked eye viewing unless you have entirely dark skies.

I realize it has been a cloudy week there, maybe the weekend will provide a few breaks. But midweek next week you may actually see it a bit brighter too, as well as higher above the horizon in the evening. It should be quite easy to find then as soon as sunset glow has faded to almost full darkness.

In any case these evening views will improve daily for the next week, as the comet heads a little higher and closer to the base of the Big Dipper-Plough and goes between the two faint pairs of stars that are in the constellation (the bear's feet for Ursa Major) and below the more familiar seven-star pattern.

This is a rough graphic of what to look for around 11 p.m. local time ...

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...................................................................................................................Comet 16th-17th ...

In a couple more days it heads between those two faint stars to the lower right of the Plough/ Big Dipper and by the 23rd it's below the Plough/ Big Dipper and approaching the gap between the two fainter stars to the lower left.

pad199207 · 16-07-2020 11:55pm

Nice view tonight over Kildare

lolie · 17-07-2020 12:16am

pad199207 wrote: »

Nice view tonight over Kildare

Good catch, completely cloudy out here.
Also the Iss is overhead 3 times a night for the next week or so if anyone is out star/comet gazing.

SeaBreezes · 17-07-2020 12:22am

Pic from cork

Rebelbrowser · 17-07-2020 12:35am

SeaBreezes wrote: »

Pic from cork

Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?

Pinch Flat · 17-07-2020 12:38am

Nice clear evening in Dublin 15 but cant see jack. Is it quite close to the horizon? Looking NNW

Nabber · 17-07-2020 12:49am

Pinch Flat wrote: »

Nice clear evening in Dublin 15 but cant see jack. Is it quite close to the horizon? Looking NNW

Light pollution might be an issue

SeaBreezes · 17-07-2020 12:54am

Rebelbrowser wrote: »

Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?

Below and to the right of the plough, its faint but visible to the naked eye, its the trail you will see first.

endacl · 17-07-2020 1:01am

https://skyandtelescope.org/astronomy-news/anticipation-grows-for-comets-neowise-and-lemmon/

little bess · 17-07-2020 1:17am

Yes, went to our local park In Dublin 5 and saw it before cloud cover came over here. Visible even with light pollution and without binoculars. The tail is very obvious, you won’t mistake it for a star!

M.T. Cranium · 17-07-2020 2:21am

Rebelbrowser wrote: »

Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?

Assuming your question came shortly after your view of the sky, the bright star to the left was probably Arcturus. Jupiter would be high in the south at midnight with Saturn to its left, Venus rises around 0300h local time ahead of the Sun. Mars is also visible after 0130h and is midway between Venus and Jupiter-Saturn.

M.T. Cranium · 17-07-2020 2:22am

Early risers (now to 0400h) can see Venus, Aldebaran and the crescent Moon in a tight conjunction rising in the east.

RobertKK · 17-07-2020 12:00pm

A friend in the Netherlands showed me this picture that his friend took.

Gaoth Laidir · 17-07-2020 12:04pm

RobertKK wrote: »

A friend in the Netherlands showed me this picture that his friend took.

How come no stars are visible in that photo?

pauldry · 17-07-2020 3:03pm

Do we have to go to the Nederlands to see blue sky?

Actually if you set fire to any photo for a milisecond would you get the same effect

endacl · 17-07-2020 3:06pm

Gaoth Laidir wrote: »

How come no stars are visible in that photo?

Too bright for the stars to show up, and slightly cloudy over most of the image.

Oneiric 3 · 18-07-2020 6:50am

Great capture in the UK:

https://twitter.com/ST0NEHENGE/status/1282622083130888192

oriel36 · 18-07-2020 7:12am

The distance from observer to horizon acts like a giant sun visor to events close to the inner solar system or where the Sun's glare swamps observation. Nowhere is this more apparent than the ISS where the horizon is the Earth itself -

https://www.youtube.com/watch?v=Yh1_wHdUx3Y&t=114s

In a mini version of this, the distance from observer to horizon as a twilight appearance shows objects close to the left of the Sun while a dawn appearance shows objects to the right of the Sun. This is why comet neowise is to the left of the Sun and will become a largely twilight appearance as viewed from the orbital plane of the Earth.

https://theskylive.com/planetarium?objects=sun-moon-c2020f3-mercury-venus-mars-jupiter-saturn-uranus-neptune-pluto&localdata=51.48%7C0%7CGreenwich%2C+United+Kingdom%7CEurope%2FLondon%7C0&obj=c2020f3&h=12&m=15&date=2020-07-17#ra|7.879943777327864|dec|42.32479332747845|fov|80

There is nothing offensive in this description, however, those who choose to express the comet in terms of a plethora of objects rising and setting based on daily rotation fall far short of the relationship of the comet to the moving Earth and the stationary/central Sun. Far more enjoyable and challenging this way as it is much more than just identification. It is not for everyone but for those who can, there is a satisfaction involved like no other,at least in these matters.

M.T. Cranium · 18-07-2020 7:35am

Getting brighter, I just got in from a clear sky late evening view here, and would say it has brightened by perhaps 20 or 25 per cent over two days. It is closing in on the first pair of stars shown in my earlier diagram (lower right of the bowl of the Big Dipper). If you get a chance this evening in any part of Ireland, it can be located from this chart although you'll probably see the comet before you find the two stars it is approaching. The next night it should be moving through that gap (possibly before your turn so I may see that from here on Sunday evening).

So I have taken the original diagram and edited it as follows for tonight (19th 00z roughly).

.................................................NW.......................................................NNW......
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...................................................................................................Comet 18th-19th ...................

(the comet is steadily moving right to left or west and will eventually be near the next pair of stars shown
below the handle of the plough/dipper.

oriel36 · 18-07-2020 9:30am

M.T. Cranium wrote: »

(the comet is steadily moving right to left or west and will eventually be near the next pair of stars shown
below the handle of the plough/dipper.

It takes quite an effort to translate the transition from a morning appearance to an evening appearance of a celestial object or as it moves from right to left of the Sun as viewed from the orbital plane. You are trying to include daily rotational East and West coordinates and that defeats the whole purpose of relating the comet to the central Sun and the moving Earth.

The Earth is constantly shifting axial orientation to the Sun as the North pole moves in a small circle parallel to the orbital plane over the course of a year like so -

https://qph.fs.quoracdn.net/main-qimg-bc3b5688f8ec0f30f7823b47576d1341.webp

Unfortunately a moderator sought to close down the other thread for some unwarranted reason of anger which I don't have as untangling the issue of what is left or right of the Sun or from a dawn to twilight appearance can be challenging at first for any observer. It intersects with weather and seasonal weather patterns in the way the original framework of Copernicus (which needed modification anyway) was lost to the 17th century RA/Dec modelers who attempted to make the Earth's daily rotation the basis for observations.

The graphic above is accounted for in a description of Copernicus which he jettisoned by the time he wrote De Revolutionibus. It would take 500 years until the emergence of satellite imaging to demonstrate what that motion parallel to the orbital plane looks like -

"The third is the motion in declination. For, the axis of the daily rotation is not parallel to the Grand Orb's axis, but is inclined [to it at an angle that intercepts] a portion of a circumference, in our time about 23 1/2°. Therefore, while the earth's center always remains in the plane of the ecliptic, that is, in the circumference of a circle of the Grand Orb, the earth's poles rotate, both of them describing small circles about centers [lying on a line that moves] parallel to the Grand Orb's axis. The period of this motion also is a year, but not quite, being nearly equal to the Grand Orb's [revolution]. The Grand Orb's axis, however, being invariant with regard to the firmament, is directed toward what are called the poles of the ecliptic." Copernicus

http://copernicus.torun.pl/en/archives/astronomical/1/?view=transkrypcja&

In conclusion, when the comet moves from right to left of the Sun as it has been doing over the last week or so, the description is based on how we see the comet from the orbital plane of the Earth. It is why the ISS imaging is so compelling in this respect -

https://www.youtube.com/watch?v=Yh1_wHdUx3Y&t=122s

The more observers become familiar with the astronomical relationships involved with the comet, the more the curtain rises on the satisfaction gained by linking the motions of the planet to weather and climate as they truly exist.

Meteorite58 · 19-07-2020 12:23am

Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.

BugUeTd.jpg?1

Purple Mountain · 19-07-2020 12:25am

Meteorite58 wrote: »

Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.

What time will Bob and Doug and the Russians zoom past again tonight?

quad_red · 19-07-2020 12:48am

Meteorite58 wrote: »

Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.

Went out there myself. Wall of cloud.

quad_red · 19-07-2020 12:50am

Meteorite58 wrote: »

Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.

Ah good stuff.

Went out myself and bank of cloud where it should be. Waited a while to see if it would move but no luck.

Will try again tomorrow.

Comet NeoWise

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