87 votes
Accepted

How was New Horizons able to direct data so precisely back to Earth?

The high gain antenna of New Horizon as an opening angle of its beam of about 0.6°. That means, it has to be pointed at Earth with an error margin of 0.3°. As a practical example, this is more like ...
asdfex's user avatar
  • 15k
38 votes
Accepted

Why no recent information about or photos of Ultima Thule?

New Horizons was hidden behind the Sun a few days after the flyby, from January 4th to January 7th. Almost as soon as the encounter and earliest downlinks are over, New Horizons will go into solar ...
Hobbes's user avatar
  • 128k
37 votes

Could one of the interstellar probes discover Planet IX by accident?

Any hypothetical planet (or other object) even further out would be very dark, so few photos are taken for any reason other than to look inward. (And in any case, the cameras on the Voyagers are shut ...
GremlinWranger's user avatar
31 votes

Where will the Pioneer, Voyager and New Horizons spacecraft be after one galactic orbit?

Oversimplifying by taking the current velocity of each probe and multiplying it by 250 million years, I get: Voyager 1 - 10,000 light years away Voyager 2 - 9,600 light years away New Horizons - 9,...
Eugene Styer's user avatar
  • 1,852
27 votes

Why no recent information about or photos of Ultima Thule?

In addition to the limited downlink time due to it being hidden behind the Sun, it should be noted that the New Horizons team is prioritizing downlinking the metadata of each of the images. This will ...
PearsonArtPhoto's user avatar
  • 121k
25 votes

Could one of the interstellar probes discover Planet IX by accident?

There are five probes leaving the Solar System. Pioneer 10 and 11 are no longer functioning. Voyager 1 and 2 are functioning but their cameras have not been used since the early 1990s, and it is ...
Andrew is gone's user avatar
24 votes
Accepted

How much longer would New Horizons take to reach Pluto without the Jupiter slingshot?

It was said in here that the time to reach Pluto was shortened by 3 years. It's also said that after the Jupiter flyby the probe gained ~ 4 km/s accelerating to the speed of 23 km/s relative to the ...
OON's user avatar
  • 1,684
23 votes

How come there are so few TNOs the Voyager probes and New Horizons can visit?

It's a small matter of propulsion, or rather a matter of small propulsion. Pluto orbits just over 5 billion kilometers from the sun, if you look at the volume of the space between 5 billion km and 8 ...
GdD's user avatar
  • 20.3k
21 votes

Where will the Pioneer, Voyager and New Horizons spacecraft be after one galactic orbit?

We don't know as there's no way to calculate it exactly. To do so we'd have to have extremely accurate data on every gravitational interaction these space probes will ever be exposed to. This would ...
GdD's user avatar
  • 20.3k
20 votes
Accepted

How tall are Pluto's mountains? Are they the tallest ice features in the Solar System?

How tall are these things? Are they made of ice? Are they the tallest things on Pluto? Are these the tallest ice features in the Solar System? "New close-up images of a region near Pluto’s ...
ceejayoz's user avatar
  • 1,278
20 votes
Accepted

Could New Horizons take a "Pale Blue Dot"-like image this year?

From the Johns Hopkins University page: It is possible that another flyby target can be found and reached with New Horizons' remaining fuel supply. And after that? Another exciting possibility ...
Uwe's user avatar
  • 49k
18 votes
Accepted

Why did New Horizons have to be spin-balanced to grams-level precision? (With quarters!)

I am familiar with the spin dynamics of both New Horizons and Ladee, since I performed nutation fuel slosh tests on models of the spacecraft in my drop tower facility, Applied Dynamics Laboratories, ...
jon harrison's user avatar
16 votes

What time will news from New Horizons' Arrokoth (2014 MU69) encounter become available to the public?

In simple explanation, we won't able to know what's up with New Horizons right away. The probe will be busy collecting all the science data during the high-speed flyby. Closest approach will be at ...
not_Prince's user avatar
  • 1,507
16 votes

Could one of the interstellar probes discover Planet IX by accident?

Planet Nine semi-major axis is estimated to be 400 AU to 800 AU. New Horizons is now about 50 AU away from the Sun and travels about 3 AU per year. So in about 120 years New Horizons will be 400 AU ...
Uwe's user avatar
  • 49k
16 votes

Could one of the interstellar probes discover Planet IX by accident?

It is actually pretty likely we have seen Planet 9, but just don't know that it is in fact moving. The problem is to know something is an object in the solar system, we have to see it move, and an ...
PearsonArtPhoto's user avatar
  • 121k
15 votes
Accepted

Are there any accurate velocity plots of all spacecraft that achieved escape velocity from the solar system? (Pioneers, Voyagers, & New Horizons)

Wikimedia has the following graph for the heliocentric velocities of both Pioneer probes: (SVG) As far as I can tell it's accurate, since it clearly shows the velocity change of Pioneer 10 during its ...
SE - stop firing the good guys's user avatar
14 votes

How much longer would New Horizons take to reach Pluto without the Jupiter slingshot?

Depending on the time of launch, there were 4 different major plans for the NH mission profile. The first 3 involved Jupiter flybys, and would have an arrival date of 2015, 2016, or 2017. The last was ...
PearsonArtPhoto's user avatar
  • 121k
12 votes

Did New Horizons also demonstrate the "Pioneer Anomaly"?

I found this reference in a 2015 Reddit interview of the New Horizons team: Has the team had any success looking for Pioneer Anomaly type effects in New Horizon's position and trajectory data? Thanks ...
Hobbes's user avatar
  • 128k
10 votes
Accepted

What's after the Kuiper Belt for New Horizons?

RTG power will drop below the level needed to run the transmitter sometime in the 2030s. We can still communicate with the Voyagers, which are 3 times further away than New Horizons. NH is more ...
Hobbes's user avatar
  • 128k
10 votes
Accepted

What caused New Horizon's so-called "40-year glitch"?

I found a bit more detail by googling for "New Horizons Anomaly Review Board Report". The best writeup was from here. By 4 p.m., the mission's Anomaly Review Board had convened to be briefed on ...
Organic Marble's user avatar
10 votes
Accepted

Why is New Horizons' data transmission speed so slow compared to Voyager?

The phrase "limited by ability to capture 1.4 kbit/s data using a 70 m/34 m antenna array" indicates they used 2 large dishes to receive Voyager's signal, which takes up a lot of DSN resources (only a ...
Hobbes's user avatar
  • 128k
10 votes

How come there are so few TNOs the Voyager probes and New Horizons can visit?

Try to imagine a planetary walk. All distances and diameters are scaled down by a factor of 1E-9 or 1 to 1 billion. On such a walk the Sun is a sphere of 1.4 m diameter. From Sun to Earth you have to ...
Uwe's user avatar
  • 49k
7 votes

How does New Horizons handle unexpected gravitational effects near Ultima Thule?

Course changes from unknown objects will be tiny. We detected MU69 from Earth, and it's only 30 km across. So 'matter we cannot observe' is going to be smaller than that and be too light to make much ...
Hobbes's user avatar
  • 128k
7 votes
Accepted

What angular resolution is expected during New Horizon's flyby of Ultima Thule?

Update 2019-01-01: I've calculated detailed resolution and range values for the encounter's imaging schedule. The chart can be found in this answer (scroll down to Resolution during capture in meters ...
Alex Hajnal's user avatar
  • 1,971
7 votes
Accepted

Did New Horizons also demonstrate the "Pioneer Anomaly"?

There are at least three independent models for the thermal recoil force that were applied to the Pioneer spacecraft. The results of all of them are compatible with the observed anomaly, which is a ...
Paulo Gil's user avatar
  • 330
7 votes
Accepted

How are precision trajectory measurements made of trans-Neptunian spacecraft?

Doppler and ranging are used routinely. They are both two-way, with the Doppler turning the frequency around and the ranging turning around a pseudo-noise signal. This is complicated, only for these ...
Mark Adler's user avatar
  • 58.2k
7 votes

Is New Horizons' transmission of data from the Arrokoth flyby completed?

From http://pluto.jhuapl.edu/News-Center/PI-Perspectives.php "Once New Horizons exits hibernation, our pace of activity will pick up dramatically. We’ll begin by downlinking the science data from ...
Cathryn's user avatar
  • 71
6 votes
Accepted

Timing shadows from the Kuiper belt! Any news? Did it work?

One of the scientists involved wrote a blog post for the Planetary Society dated June 16, 2017: “What about the results? Did you see the occultation?” you ask. Everyone asks this. Right now, we don’t ...
Hobbes's user avatar
  • 128k
6 votes

How does New Horizons handle unexpected gravitational effects near Ultima Thule?

What are the navigation techniques used to handle the aggregated unknown effect of gravity from local and distant matter for the New Horizons space probe when it intercepted Ultima-Thule ? ...
David Hammen's user avatar
  • 74.8k
6 votes
Accepted

Does JPL's Horizons have better MU69 state vectors for the New Horizons flyby somewhere?

Thanks to Jon. D. Giorgini at NASA JPL for pointing out that there is indeed a much newer solution in Horizons. The trick is to use the newer, though unofficial designation Ultima Thule when ...
uhoh's user avatar
  • 149k

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