New Horizons to flyby Pluto this year

[Ray McCarthy]

passed through our Solar System 70,000 years ago

Sort of!

Estimates indicate that the WISE 0720−0846 system passed about 52,000 astronomical units (0.25 parsecs; 0.82 light-years) from the Sun about 70,000 years ago

Kuiper belt: 30 AU to approximately 50 AU from the Sun.
Oort Cloud: 100,000 AU from the sun. About 2,000 further away than any known object other than comets. Unlike the Kuiper belt which is a torus or doughnut shape (hence "belt") roughly in the plane of the ecliptic, the Oort Cloud is presumed like a very thin "shell". We can't at all detect parts that are in direction of the more obvious parts of Milky way.

So it might have disturbed the orbits of some comets (or maybe nothing) in the Oort Cloud as we know little about it apart from comets that have been documented in Solar orbit (which were not affected).

EDIT:
Eris and its moon are the furthest known objects in the Solar System, on an elliptical orbit 38 to 98 AU orbit (Perihelion to Aphelion), so Scholz's star just a little less than 1000x as far as the mean of Eris's orbit. It's very unlikely to have been visible. If orbital period given in Wikipedia is correct, then for Eris, the passage of Scholz's star (WISE 0720−0846 system) was only 125 orbits (Eris "years") ago!

 

[Serendipity]

Sort of!

Kuiper belt: 30 AU to approximately 50 AU from the Sun.
Oort Cloud: 100,000 AU from the sun. About 2,000 further away than any known object other than comets. Unlike the Kuiper belt which is a torus or doughnut shape (hence "belt") roughly in the plane of the ecliptic, the Oort Cloud is presumed like a very thin "shell". We can't at all detect parts that are in direction of the more obvious parts of Milky way.

So it might have disturbed the orbits of some comets (or maybe nothing) in the Oort Cloud as we know little about it apart from comets that have been documented in Solar orbit (which were not affected).

EDIT:
Eris and its moon are the furthest known objects in the Solar System, on an elliptical orbit 38 to 98 AU orbit (Perihelion to Aphelion), so Scholz's star just a little less than 1000x as far as the mean of Eris's orbit. It's very unlikely to have been visible. If orbital period given in Wikipedia is correct, then for Eris, the passage of Scholz's star (WISE 0720−0846 system) was only 125 orbits (Eris "years") ago!

Sedna is a trans-Neptunian minor planet that whose orbit's closest approach is 76 astronomical units (perihelion), aphelion is c. 936 astronomical units. Its semi-major axis is 524 astronomical units. See https://en.wikipedia.org/wiki/90377_Sedna for more details.

 

[hardsciencefanagain]

and:
http://home.dtm.ciw.edu/users/sheppard/pub/TrujilloSheppard2014.pdf

 

[Ray McCarthy]

Interesting, obviously the Eris article I read was out of date.

Sedna is a trans-Neptunian minor planet

It's not an object like Pluto or Eris. Too far away to be influenced by Neptune:

It is a Detached KBO. Its perihelion (closest approach to the Sun) is at 76 AU. This means that it is effectively beyond the scattering influence of Neptune. This is unlike the Classical KBOs, and unlike the Scattered KBOs. It is similar, dynamically, to 2000 CR105 (for which a/e/i = 227AU/0.805/22.7) which has perihelion at 44 AU, also outside Neptune's reach, and which has been discussed in papers by Gladman et al (Icarus 157, 269, 2002) and Emelyanenko et al (Monthly Notices RAS, 338, 443, 2003). Other objects have larger aphelia than Sedna's 990 AU (e.g. Kuiper Belt Object 2000 OO67, with aphelion at 1010 AU) and many comets travel to larger distances. Sedna is interesting because of its perihelion distance.

Estimated 11,000 year orbit! A cold dark place. The sun a mere pinprick of light and stars visible in daytime sky.

I wonder how many objects there are of any significant size between the regular Kuipner Belt and the Oort Cloud. Will New Horizons spot something new before we lose communications with it?

 

[hardsciencefanagain]

any use?
i've deleted the links...

 

[Ray McCarthy]

I can't go downloading PDFs without knowing size. In browser viewing is a nonsense and should be disabled. It downloads a temporary copy and makes your browser vulnerable to freezing, malware or crashing.

One article incorrectly claims Sedna is part of Oort cloud, even at furthest distance from sun it's not even at inner edge:

Warning LOG scale

Larger sizes:
https://en.wikipedia.org/wiki/File:PIA17046_-_Voyager_1_Goes_Interstellar.jpg

We lose communication with New Horizons long before 100 AU, beyond 55AU the communications link will become too weak. Pluto is on inner part of orbit at the minute, Neptune is about 30 AU away. Pluto varies from about 29 to 49 AU and right now is only slightly further away than Neptune.

 

[BAYLOR]

After the Oort cloud Next stop Alpha Centauri. I look forward to those picture. Of course, it could be a while before the Craft gets there.

 

[Ray McCarthy]

If ever ... the graph is logarithmic* to compare distances and not direction and I have no idea which direction out of the Solar System that Voyager 1, Voyager 2 and New Horizons are headed. The last images will be roughly when it has travelled only 55AU. Voyager has, I think, a plutonium source generating heat and any electricity needed via thermo-electric (thermocouple?) devices.

Voyager 1 is a space probe launched by NASA on September 5, 1977, to study the outer Solar System. Operating for 37 years, 10 months and 11 days the spacecraft still communicates with the Deep Space Network to receive routine commands and return data. At a distance of about 131.982 AU (1.974×10^10 km; 0.002087 ly), it is the farthest spacecraft from Earth.

Evidently the New Horizons has very much less communications life as communications will cease at about half the distance Voyager 2 has reached.

Voyager 2 is a 722 kg (1,592 lb) space probe launched by NASA on August 20, 1977 to study the outer Solar System and eventually interstellar space. It was actually launched before Voyager 1, but Voyager 2 was sent on a different trajectory and arrived at Jupiter and Saturn after Voyager 1. Voyager 2 has been operating for 37 years, 10 months and 28 days as of 18 July 2015, and the Deep Space Network is still receiving its data transmissions. At a distance of 108 AU (1.62×10^10 km) from the Sun as of April, 2015, it is one of the most distant man-made objects (along with Voyager 1, Pioneer 10 and Pioneer 11).

[* if it was NOT logarithmic, everything from the Sun to Kuiper Belt would only be ONE PIXEL on your screen with Oort Cloud on the other edge and the neighbouring stars not shown!]

 

[Serendipity]

Above was doodling with the dwarf / minor planets in the Kuiper Belt. Please bear in mind my drawing skills are very limited, especially in powerpoint.

 

[Dave]

I have no idea which direction out of the Solar System that Voyager 1, Voyager 2 and New Horizons are headed.

The Voyagers both went off out of the orbital plane so they are unlikely to ever encounter anything else again. I think New Horizons must also be slightly outside the orbital plane because Pluto has an eccentric orbit that is slightly out of the plane. As someone just said, the power will probably run out before they ever reached the Oort Cloud in any case.

 

[Ray McCarthy]

I suspected that.

 

[Ray McCarthy]

New Horizons Pluto Mission a success:
http://www.theregister.co.uk/2015/07/21/new_horizons_pluto_mission_resounding_success/

 

[Vertigo]

Did anyone else see the Sky at Night special on New Horizons last night? I recorded it and only watched it today. To be honest if you've being staying up to date with everything as it has come in then there wasn't really much new.

But there was one very interesting theory to do with the young surface. It is currently thought that Charon was formed when another large object collided with Mars and it has always been assumed that his happened a very long time ago but maybe it wasn't quite so long ago. Maybe Charon is actually the youngest known object in the solar system. This could explain the absence of craters, the mountains etc.

Interesting thought.

Edit: Hmm... just thought of a problem with that scenario; a relatively recent event, say in the last few hundred million years, would likely leave both bodies hot enough to still be active today, but would that be enough time for them to have become mutually tide-locked?

 

[Ray McCarthy]

Sky at Night special on New Horizons last night?

Rats. I forgot!

 

[Mirannan]

Rats. I forgot!

Should be on Iplayer?

 

[Ray McCarthy]

Should be on Iplayer?

No use here for various reasons. Some of the Radio programs work, all the TV is blocked even though it's all on Freesat (all of Ireland), Freeview (about 30% of Ireland), Sky Ireland (all of Ireland) and UPC Ireland (Cities & larger towns only).

Besides I don't have enough data cap. We don't usually watch ANY internet video at all. Instead I have two PVRs, a Humax and also a PC. Satellite Distribution system with four satellites, and aerial distribution system. We sometimes buy DVDs. People in the cities and larger towns can get Broadband with no data cap (It's actually really about 250 GByte, but only persistent high usage gets throttled and letters looking for money.). We are on a special fixed wireless link, so throttling to 64K (0.064M bps) is automatic if usage is exceeded until usage drops under 80% in rolling 30 days. Otherwise greedy people would make the service too slow as contention would rise. This is why "unlimited" data on Mobile is an oxymoron. It means everyone gets a slower service and 10% of people (paying same money) are using 90% of traffic. I used to work for an internet company. Unless there is fibre all the way and massive capacity, "unlimited" just means slow and a minority of torrent & video users getting subsidised by the majority.

 

[Dave]

Instead I have two PVRs, a Humax and also a PC. Satellite Distribution system with four satellites, and aerial distribution system.

Ray, if your rural Ireland house has all that on the roof your neighbours must think you are a government communications headquarters! However, we digress...

 

[Ray McCarthy]

I didn't mention my numerous Amateur Radio and listening aerials. I did have four dishes for a while. I cut back to one 110cm motorised and one 95cm with four LNBFs for four satellites (An LNB mounted to west of main LNB will pick up a further east satellite).
I have one 45ft mast as well as three poles on the roof.
A friend has a 3.7m mesh dish with dual A-Z motors never assembled. I'd love to have that on the shed roof as basic radio telescope.

If I had an elevation motor on my 3m long UHF/VHF array it could do moon bounce and some Stellar radio reception.

 

[Vertigo]

Rats. I forgot!

I wouldn't worry too much; you've been staying up to date with everything here as it's been happening and they didn't really have any privileged access other than interviews with the scientists and even they didn't really say anything more than has already been reported and discussed here. Other than that one theory about a recent collision which one of the scientists mentioned, there was little new material. They did go see a lab experiment showing how Nitrogen + methane + UV light does actually produce a reddish powder which is where they think Pluto's colour comes from but again the only thing there that was new was actually seeing the experiment and the tholin it produced.

But there were no new images or further speculation, so you've not missed much.

 

[Ray McCarthy]

Better photos of Nix and Hydra
http://www.theregister.co.uk/2015/07/22/giant_red_jelly_bean_found_orbiting_mountainous_pluto/