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With my expensive eclipse equipment (a Jacob's cream cracker and a piece of A4) I can see the nibble that has been taken out of the sun. I hope it stays a little clear in the south-east.

Will this be the best eclipse photo on TPF..??

Raindrops on window also acting as lenses, though somewhat blurry.

Remarkably dark now, with the sun shining.

South London still 100% cloud. Useless. Also dark as happens every day just before sundown.

Well it was spectacular here in the end. The whole deal. Saw it through glasses, saw it reflected in tinted windows, saw it clearly through light cloud. The darkness was quite, quite odd - long shadows like a summer evening, at 9.30 am.
I look forward to Derek's photos but I have now experienced the mechanics of the universe.

Zoom in...

There was no eclipse. It's just an early April Fool's hoax organised by DRT and DJ. It was cloudy, the clouds were thick and dark. Then at lunch-time the clouds parted, the sun came out and life was good.

If there had been an eclipse surely I would have seen a bit of the sun missing. Like when you take a bite out of a Cadbury Crème Egg.

Like what I saw, you mean Alex?

There was an eclipse. I photographed it through a Jacob's Cracker...

Lovely photos Derek and thanks for posting. Glad you had a good view. I asked my students, this afternoon, if they'd seen it, and they couldn't see it at all, only 60 miles away from Belfast. We were lucky!

Nice photos all, both Derek's "proper" ones, and I love the cracker photo too!
It was a beautiful, clear day in Perth also, saw the start of the eclipse, and had time just for a brief glimpse around the peak eclipse point. Didn't seem to darken quite as much as I remembered from back in '99(?), though that time I was able to view the whole thing rather than snatching glimpses when able this time. However given the expected weather, was pleased to see anything, let alone have a totally clear view.

I hope I can get as good of pictures during the 2017 eclipse that runs smack across the center of the US.

A meteor shower is predicted tonight across the UK on the twittersphere, can our resident Brian Cox tell us which way to face?

Derek has been photographing an asteroid. He sent some pictures, here strung together in a gif.

LGTrotter wrote:A meteor shower is predicted tonight across the UK on the twittersphere, can our resident Brian Cox tell us which way to face?

The Lyrid meteor shower peaks in the early hours of tomorrow morning but has already started.

You need to find the star Vega, a very bright star in the constellation Lyra. At around midnight it will be directly to the east...
Once you find Vega look slightly to the right, that is the point in the sky where the meteors emanate from...
Good luck - I'm off to bed with Man Flu

This week's astronomical news is:

1. It's been raining for days. Or is it weeks?

2. The Philae Lander has woken up!

3. At sunset on 30th June, above the eastern horizon, Venus and Jupiter will appear to be separated by less than the apparent width of the Moon so will be a lovely target in either binoculars or a small telescope.

4. It is still raining.

DRT wrote:The Philae Lander has woken up!

BBC drew my attention to that. Jolly good news. Let’s see how it is positioned, and whether it can do anything useful.

jdaw1 wrote:

DRT wrote:The Philae Lander has woken up!

BBC drew my attention to that. Jolly good news. Let’s see how it is positioned, and whether it can do anything useful.

It seems to have been writing some rather strange Tweets.

djewesbury wrote:

jdaw1 wrote:

DRT wrote:The Philae Lander has woken up!

BBC drew my attention to that. Jolly good news. Let’s see how it is positioned, and whether it can do anything useful.

It seems to have been writing some rather strange Tweets.

He's only ten years old. I suppose it's just an age thing

My first attempt at solar photography...

And watch out for some fantastic pictures and new discoveries from New Horizons in the next few days. Very impressive flying.

DRT wrote:And watch out for some fantastic pictures and new discoveries from New Horizons in the next few days. Very impressive flying.

More accurately, over the next few days it will be taking pictures that we hope will be impressive. It’ll take 16 months of non-broadband for them all to arrive. Slow download!

jdaw1 wrote:

DRT wrote:And watch out for some fantastic pictures and new discoveries from New Horizons in the next few days. Very impressive flying.

More accurately, over the next few days it will be taking pictures that we hope will be impressive. It’ll take 16 months of non-broadband for them all to arrive. Slow download!

More accurately, it will be taking thousands of pictures of Pluto and it's moons during the closest parts of the flyby, which will last less than a day, during which time it will stop all other functions including communication with Earth to maximise the resources available for the science stuff. It will then re-commence sending images to earth and continue to do so for many months. There is no reason to think we will not see close-up pictures within the next few days. Eighty two pictures have been published by NASA here that were taken between 1st and 9th July, a period that included three days out of commission due to "an anomaly".

The highly processed images and scientific experiment results may take a while to be published, but there will be pictures next week.

Also, it’s hiding behind its umbrella. It is using the radio dish as protection against any dust particles — quite important when travelling at 9 miles a second.

jdaw1 wrote:Also, it’s hiding behind its umbrella. It is using the radio dish as protection against any dust particles — quite important when travelling at 9 miles a second.

Indeed. Let's hope nothing hits the umbrella otherwise it would all have been for nothing.

Does this mean that the Oort cloud will be visited soon? Or has Voyager got there already, all unbeknownst to me?

LGTrotter wrote:Does this mean that the Oort cloud will be visited soon? Or has Voyager got there already, all unbeknownst to me?

Here is a nice explanation for you. Hew Horizons is currently just past the number 10 on the scale...

It has taken almost a decade to travel 9AU (1 astronomical unit, being the Sun>Earth average distance) and has to travel 220 times that distance through the Kuiper Belt to reach the Oort Cloud. Don't wait up.

DRT wrote:

jdaw1 wrote:Also, it’s hiding behind its umbrella. It is using the radio dish as protection against any dust particles — quite important when travelling at 9 miles a second.

Indeed. Let's hope nothing hits the umbrella otherwise it would all have been for nothing.

It appears this is incorrect.

Download this app (Mac only) to see what will actually happen over the next few days. Once the app launches hit the preview button (top left) and then crank the time rate (bottom centre) up to 30min/sec. You will see New Horizons spinning around to point its instruments at various objects in the Pluto system during the approach. When it points to Earth it is presumably sending back data. When the counter (bottom left) gets close to nearest approach slow the rate down to 1m/sec for a good look at what New Horizons is doing in that critical hour as it passes through the Pluto system. Less than an hour later it is pointed at Earth for a prolonged period. A few hours after that we will see the first picture.

Until a few weeks ago the best picture we had of Pluto was this...
Yesterday New Horizons sent us this...
The pictures we are getting now are at a resolution of 17km per pixel. At closest approach we will see 100m per pixel, which I am reliably informed is as detailed as we have seen any other Solar System object from above the surface.

As our friend would say - woo woo!

Thank you for the update regarding the Oort Cloud. I think I found the name so inviting I could not resist mentioning it and the diagram I looked at of it seemed to show it a bit nearer than yours. It is all rather lovely these photos of Pluto, please post more when you get them. Is it Sedna next?

LGTrotter wrote:Is it Sedna next?

There are no plans to visit Sedna. If we were to, it should be later this century, but there are no plans for that.

LGTrotter wrote:Is it Sedna next?

The [url=https://www.nasa.gov/mission_pages/newhorizons/overview/index.html]NASA mission page for New Horizons[/url] wrote:As part of an extended mission, the spacecraft is expected to head farther into the Kuiper Belt to examine one or two of the ancient, icy mini-worlds in that vast region, at least a billion miles beyond Neptune’s orbit.

I do not know whether or not the targets have been chosen. Much will depend on where the various KB objects are in their orbit around the Sun. Sedna takes 11,400 years to do that so a whole lot of fortunate circumstance will have to fall into place if New Horizons is going to make it anywhere close to another significant object anytime soon.

New Horizons is moving fast, and its remaining smidge of fuel can do only small changes of direction. Three possible next targets were identified by Hubble in the last few years, but they’re all nameless rocks, perhaps a few dozen km across.

Edit: see “Suitable KBOs” in this wikipedia page, and also see 2014_MU69.

Unfortunately I can't quote DRT's New Horizon's picture of Pluto, but I swear I can make out some branding and a vintage date upside down at the bottom of the sphere. It looks like
"..64
..N..
..C.."

Any idea who the shipper might be?

Nasa reports that New Horizons has phoned home to say that it is alive and full of pictures.

Phew!

Pictures will come over the next 1⅓ years.

jdaw1 wrote:Pictures will come over the next 1⅓ years.

Just before it went out of contact we did also get the following image which is much higher resolution than all previous, though I am sure will be superseded over the next few days:

I watched the "phone home" session live at around 2am this morning. It was quite a heart warming site to see transition from tense anticipation to relief and elation on the faces of so many people who have dedicated the best part of their careers to such a major achievement.

They now need to stop messing around and send us some pictures!

I am reliably informed that the first high resolution pictures have now been received and processed by NASA and will be released at 20:00 this evening.

Is it too early to speculate why there are no impact craters on Pluto? And how does vulcanicity work in such circumstances, without the gravitational heating thing?

Nasa has a page showing Views of Pluto Through the Years. The first image of that is as follows.

To a casual observer this seems taller than wide. Could the positions of Pluto and Charon be superimposed on this? That is, might the apparent ‘tallness’ have been caused by Charon?

DRT: if so desired, re-post this where an answer might be forthcoming (though linking back to here).

LGTrotter wrote:Is it too early to speculate why there are no impact craters on Pluto? And how does vulcanicity work in such circumstances, without the gravitational heating thing?

I have a theory that you might wish to ponder, challenge, refute or ridicule at your leisure.

The early Earth was once struck by a large planetary object. The impact ejected matter into orbit around the Earth that eventually formed the Moon - a geologically dead world that has subsequently been covered almost entirely with impact craters. The Earth, being larger and having suffered the energetic thump of the impact still to this day has a molten core, vulcanicity, plate tectonics and almost no craters.

Pluto and Charon could be very similar to the Earth and the Moon, only smaller, colder and from an impact that is much closer to today than when the Earth and Moon-creating object hit one another. So Pluto is, or was astronomically recently, still alive and re-generating its surface, whilst Charon is half way towards being as dead as our Moon.

Thoughts?

jdaw1 wrote:Nasa has a page showing Views of Pluto Through the Years. The first image of that is as follows.

To a casual observer this seems taller than wide. Could the positions of Pluto and Charon be superimposed on this? That is, might the apparent ‘tallness’ have been caused by Charon?

DRT: if so desired, re-post this where an answer might be forthcoming (though linking back to here).

To my eyes that picture is four pixels by four pixels. I suspect the light and dark are simply a very low resolution depiction of the very large patches of dark and light that we can now see clearly.

DRT wrote:of the very large patches of dark and light that we can now see clearly.

The largest of which is Charon. Is it possible to know, as of that picture, whether Pluto-Charon was up-down or left-right. Or even if one was transiting the other?

DRT wrote:The Earth, being larger and having suffered the energetic thump of the impact still to this day has a molten core

Core heat not solely caused by the impact. The Theia impact was a glancing blow — why the moon has less iron than the Earth, and even without that impact a large body like the Earth would have plenty of heat residual from its formation.

DRT wrote:plate tectonics

Cause by molten core.

DRT wrote:and almost no craters.

A good atmosphere causes many potential impacts to burn up before collision, and then erodes the evidence of those that hit ground. As does the tectonics, and the atmosphere-related existence of rain.

I may be a little far gone in my five am red ale for this but here goes.

In re; the Earth has a molten core which was caused by a collision in which a moon sized lump was knocked off; I don't think this can be true, I'm sure it would have made it hotter but surely it was already hot, just cooling down slowly?

Also Sharon (as in my whimsical way I have renamed her) is not even nearly round, no nor even an oblate spheroid, Julian, in case you are listening, which has no relavence except it occurred to me while I was looking a four pixels depicting Pluto.

Good work, keep it up. Any new pictures to gawp at would be welcome.

And I think that Derek is right that tectonics has more to do with the lack of impact craters on Earth than the weather.

jdaw1 wrote:

DRT wrote:of the very large patches of dark and light that we can now see clearly.

The largest of which is Charon. Is it possible to know, as of that picture, whether Pluto-Charon was up-down or left-right. Or even if one was transiting the other?

The Pluto system has an orbital plane that is at almost 90° to its orbit around the Sun. From Earth it looks like a dart board - the Moons never transit the Pluto disk from where we see it.

Pluto is approximately 1,200km in diameter. Charon is approximately 20,000km from Pluto. That is a lot of blackness that is absent in the picture shown above. If Pluto was just one of those pixels, Charon would be smaller than one pixel that was 16 to 17 pixels away in one direction.

I did not intend to suggest that a molten core was caused by a collision, but that it would add energy to the already burning fire and prolong the period over which it cooled.

Pluto can never have had an atmosphere capable of causing the surface erosion that the Earth's atmosphere does. It is too cold and too small.

The very close proximity of Pluto and Shazza are another possible explanation for their geologic activity. In cosmological terms they are very close together and are the only two bodies we know of that are doubly tidally locked.

One for Owen...

Interesting to note that the picture above seems to be a zoomed-in view of a part of the planet that is not the part that the diagram suggests.

Conspiracy theories begin with such pictures.

DRT wrote:planet

?