Questions tagged [juno]

Questions regarding the JUNO spacecraft, a NASA mission to Jupiter.

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85
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4answers
22k views

Why destroy Juno at the end of the mission?

As follows from the mission timeline: Launch - August 5, 2011 Deep Space Maneuvers - August/September 2012 Earth flyby gravity assist - October 2013 Jupiter arrival - July 2016 Spacecraft will orbit ...
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4answers
6k views

Why wasn't an RTG used on the Juno spacecraft?

When I first heard about the Juno spacecraft, I was surprised that it would be using solar panels to generate power throughout the mission. Why wasn't a radioisotope thermoelectric generator (RTG) ...
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4answers
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Is Jupiter bright enough to be seen in color by the naked eye from Jupiter orbit?

After seeing spectacular photographs of Jupiter, especially this one: I wondered if this would be visible with the naked eye from Jupiter orbit? Is the sunlight at Jupiter bright enough to see this ...
35
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1answer
7k views

Why are photos from Juno such low resolution?

NASA recently published this photo taken by Juno, at a distance of about 700,000kms from Jupiter: The overall quality (very grainy around the darker regions, a bit washed-out in the brighter areas, ...
33
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1answer
3k views

Why does this image of Jupiter look so strange?

The Universe Today's Yes, This is Actually the Shadow of Io Passing Across the Surface of Jupiter shows several images of Jupiter taken by JunoCam. Why does this image look so strange? Instead of an ...
22
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7answers
6k views

How does a spacecraft know that it is in orbit?

After a 5 year long journey in space, Juno finally reached and started orbiting Jupiter. How does the probe actually know that it is in orbit, so that it can send confirmation message like 'Welcome to ...
19
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5answers
27k views

How long does it take for a signal to travel between Earth, and Juno at Jupiter?

How long would it take for Juno's communication to reach the Earth? In other words: what is the time delay between perception by Juno and perception by NASA researchers?
18
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1answer
3k views

Why does NASA's Juno spacecraft only have a one year primary mission?

For many years, Juno has been touted as NASA's "low cost" mission to the Jovian system. As a New Frontiers mission, it is cost capped at only $1 billion. From its launch in August 2011 to its ...
15
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1answer
763 views

Resilience to data transmission errors of the Juno spacecraft

What techniques have been employed for the Juno spacecraft to successfully transmit data packets back to Earth once she's in a polar orbit around Jupiter? Jupiter is a strong source of radio ...
15
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1answer
715 views

Will Juno record its deorbit?

I'm really interested about the Juno mission launched in 2011. The spacecraft will reach Jupiter on July 4, 2016, in couple days from when I write this question. It will orbit Jupiter 37 times ...
14
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1answer
1k views

How is JunoCam different from a normal CCD camera?

JunoCam has tweeted us! More background from the BBC. It is supposed to have several features that help allow it to work in the high radiation and magnetic fields it will experience during each ...
14
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2answers
3k views

How will Juno establish existence of solid core within Jupiter and determine its size?

One of the set goals for NASA's New Frontiers Juno mission is studying Jupiter's interior and determining if this gas giant has a solid core and if, how large it is. This is mentioned several times on ...
13
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1answer
401 views

What are the implications if Juno finds that Jupiter has a solid core?

Juno has arrived at Jupiter, and will begin taking measurements to determine if the gas giant has a solid core. But what I cannot seem to find is the implications such a discovery would have. This ...
12
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1answer
424 views

What is the typical power redundancy built into a spacecraft?

NASA's Juno page says The Juno spacecraft launched aboard an Atlas V-551 rocket from Cape Canaveral, Fla., on Aug. 5, 2011, and will reach Jupiter in July 2016. The spacecraft will orbit Jupiter 32 ...
11
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2answers
621 views

Will JUNO be able to return any photographs?

Looking at the scientific instruments of JUNO, there doesn't appear to be a camera. Furthermore, no mention is made of any photos being returned in the scientific objectives. Will anything resembling ...
10
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1answer
349 views

Are any software updates scheduled for Juno?

So Juno approaches seeking her gravity assist. During the course of the maneuver several on-board systems shall be powered up - in all probability they are nominal, having already been checked-out ...
10
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1answer
380 views

Does NASA use Newtonian model of gravity for plotting the course of Juno or general relativity?

With the huge mass of Jupiter and its fast, approximately 10 hours daily rotation, there may be substantial twisting of space-time around it. A distortion of such magnitude that may call for ...
10
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2answers
244 views

Will Juno be visible during its flyby?

Juno is flying by by the planet Earth on October 9, 2013. Will it be visible to the naked eye anywhere on Earth, and if so, where and when?
9
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6answers
666 views

How was Juno's arrival set up to be on the evening of July 4th?

Presumable it is largely a coincidence that Juno arrives at the perfect moment for American pride in NASA's achievements, but not entirely. The video below of the trajectory, released in July 2011 ...
9
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2answers
507 views

Can safe mode on a spacecraft be bypassed?

A sort of followup to Are any software updates scheduled for Juno? For the purpose of illustration, seeing that Juno has most recently encountered such an issue, I mention Juno here. However the ...
9
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1answer
275 views

Is there any publicly available logging, or “Wayback Machine” for DSN Now activity?

This question and especially this comment address activity associated with the Juno mission, both circa arrival, and the relatively quiet transit period to Jupiter. The idea is that there may have ...
8
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3answers
224 views

When can we (public) expect to see the first optical images of Jupiter from the Juno spacecraft?

As many of us know, Juno spacecraft achieved orbit of Jupiter yesterday (July 4, 2016). Does anyone have an educated guess on approximately when we might see the first optical images from Juno in ...
8
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2answers
132 views

How can I figure out the distance to Juno at any point in time?

Juno will fly by Earth on October 9, 2013. There is an event to encourage Amateur Radio Operators to say high to the satellite. What I'm trying to do is figure out if I have any chance of pulling it ...
8
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1answer
208 views

What is the difference in resolution between the cameras in Voyager and Juno?

Both Voyager I and the Juno spacecraft photographed Jupiter (among other things). What is the difference in camera resolution between the two spacecraft? Did we receive larger photos from Juno?
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1answer
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How is gravitational time dilation experienced by spacecraft near Jupiter such as Juno

I understand (I think) that a vehicle on or near a planet with greater mass - such as the Juno probe entering Jupiter's orbit soon- will experience time slightly slower relative to us on Earth. ...
8
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1answer
258 views

Does Juno use MPPT?

MPPT aka Maximum Power Point Tracking is an active mechanism to collect maximum power a PV cell may deliver. This is typically achieved by varying the resistive load connected to a cell. Juno will ...
8
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0answers
335 views

What exactly is the interaction that blocked Juno's data downlink near solar conjunction?

According to Space.com's article Juno Phones Home: Jupiter Probe Reconnects with Earth After 8th Flyby, Juno's recent close flyby of Jupiter and data collection happened while Jupiter was too close to ...
7
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1answer
212 views

Will Earth, ISS, or Tiangong be the first habitat closest to Juno during Earth Flyby 2013?

Just a fun question (+: Juno is approaching Earth for a gravity assist on her way to Jupiter. Her approach will bring her, at the nearest point, a mere 559KM above Earth's surface. ISS orbits just ...
6
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2answers
2k views

Why does the Juno spacecraft flyby Earth on the way to Jupiter?

Hohmann transfer to Jupiter is about 2 years 8 months. Juno spends 5 years getting there, almost twice as long. I note that it takes Juno 2 years 8 months to get to Jupiter after the Earth flyby, does ...
6
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2answers
2k views

When will Juno send us some pictures from it's tight orbit?

Juno probe has sent few pictures as it approached Jupiter from afar, but Jupiter looks as large as Moon on our sky on those photos. After that it went into (intentional) silence while it was trying to ...
6
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1answer
217 views

Who built Juno's chipsets?

Lockheed Martin was responsible for the construction of Juno. But I was wondering who built the chips Juno uses for its onboard computers, and whether or not they are radiation hardened. I would ...
6
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1answer
292 views

What theories is Juno expected to confirm?

According to the Wikipedia article on Juno, the data that Juno returns will sift through multiple competing theories for Jupiter's formation. However the more theories that one has, the more likely ...
6
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1answer
339 views

How did the upper stage of the Juno 1 rocket change its orientation while it was spinning?

The upper stage of the Juno 1 rocket was spun up to a high speed prior to launch so it would be spin stabilized and not require a guidance system. After the upper stage separated from the 1st stage it ...
6
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2answers
199 views

Why do Juno's solar panels narrow toward the core?

I'm no engineer, but if I was making a vessel with extending sails, solar panels, mast, antennae, etc. I would make them widest close to the core. But Juno's solar panels narrow toward the core as ...
5
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4answers
663 views

The plane of the orbit of Juno around Jupiter is not the ecliptic plane. How did it get into this plane?

Did Juno start off its course on the ecliptic plane from the earth orbit and then left it at insertion to Jupiter's orbit over its north pole or it was always in that plane?
5
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1answer
173 views

Why did Cassini have reaction wheels but Galileo, Juno and New Horizons don't?

Three gas giant planet orbiters are mentioned in this answer: Cassini - Uses Reaction Wheels and thrusters Galileo - Primarily managed via spinning the spacecraft and thrusters. Juno - Just ...
5
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1answer
619 views

Why are these multi-junction solar cells 40% efficient on earth but 30% in space?

This video about Spectrolab's spacecraft power systems mentions Juno several times and it looks like the Juno panels are shown at several points in the video. Multi-junction cells are discussed, they ...
5
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1answer
188 views

Will JUNO do any science of Jupiter's Moons?

It seems like the primary focus of JUNO is to get a better idea of how Jupiter works. The Science Objectives listed on Wikipedia don't seem to include anything about Jupiter's moons, other than a ...
5
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1answer
119 views

Given that JunoCam is mainly for outreach, how bad is it as a scientific instrument?

According to Wikipedia's article on JunoCam (and I have seen other corroborating sources): JunoCam is not one of the probe's core scientific instruments; it was put on board primarily for public ...
5
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0answers
94 views

When did deep-space probes start getting wrapped in germanium-coated film?

The NASA video Juno Engineering: Precision Matters shows the Juno spacecraft on what look like it might be a spin balance table after about 02:50 and there one can ...
4
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2answers
1k views

Why does Juno use “mixed oxides of nitrogen” oxidizer for propulsion? Which ones?

In the recent Spaceflight 101 article Rocket Burn postponed for NASA’s Juno, to remain in elongated Jupiter Orbit until December it says: Juno uses a bi-propellant main propulsion system with ...
4
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1answer
147 views

Why was the image sensor design for Juno so… odd? [duplicate]

I attended the North Eastern Astronomy Forum this year and one of the speakers was mentioning that JunoCam will not be working because of the angle of the spacecraft. He was giving a lecture on what ...
4
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1answer
309 views

JPL Horizons original reference orbit data for Juno - how to retrieve now that it's been updated?

Because of the slow helium valve responses, Juno was not instructed to execute the large delta-v maneuver to drop from the ~53 day orbit to the ~14 day orbit originally scheduled for 2016-Oct-19. I'd ...
4
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1answer
151 views

Will there be joint observations from earth and the Juno spacecraft when it reaches Jupiter?

This is a comparison of a visible light image and a radio image of the area around Jupiter's great red spot from an article in Science News. The radio data is from the VLA, and the frequency is chosen ...
4
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1answer
79 views

Does Juno's UVS have any chance to spot Europa plumes?

JIRAM has recently been proven to be useful to monitor the volcanic activity on Io, from a considerable distance. Europa Clipper will have an ultraviolet spectrograph which be pretty much a copy of ...
3
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1answer
122 views

Juno Mission. How better resolution will the optical images be to previous missions?

Resolution in km/pixel at: (i) the closest approach and (ii) typical when in close to Jupiter part of the eccentric orbit.
3
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2answers
362 views

Juno's original orbit around Jupiter - is this apsidal precession? If so, need expression

Below is a plot of Juno's originally planned orbit around Jupiter, extracted from JPL Horizons. It's shown in J2000 ecliptic coordinates, centered on the Jupiter barycenter. It turns out the orbit is ...
3
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1answer
303 views

When Juno finally de-orbits into Jupiter, will metal sink to the core, or remain in the atmosphere?

The answer would have to be best scientific guess or theory, rather than fact, but has any thought been given to what actually happens to the metallic elements of a spacecraft de-orbited into Jupiter? ...
3
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1answer
143 views

Jupiter's impact on Juno's solar panels

Juno has large solar panels on it. I was curious about their effectiveness when Juno is closest to Jupiter. Does Jupiter have a significant impact on the solar panels? Can the solar panels ...
3
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1answer
234 views

If Juno will experience lower levels of radiation than Galileo did why it will fail so much faster?

In the section about Orbit and Environment the Wikipedia article about the Juno spacecraft says: In comparison, Juno will receive much lower levels of radiation than the Galileo orbiter at its ...