Questions tagged [juno]

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

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43
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4answers
9k views

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 ...
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105 views

Did Juno just do a plane change?

There are several reports in the news that the Juno spacecraft executed a very long propulsive maneuver so that it wouldn't pass through Jupiter's shadow. Apparently it would be in dark so long that ...
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 ...
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1answer
172 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
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 ...
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 ...
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2answers
334 views

If Juno's long orbit means a lower rate of radiation damage, why the planned short orbit?

The Juno Spacecraft (also Wikipedia, launch 05-Aug-2011, Jupiter orbit insertion 05-Jul-2016) was scheduled for a burn to reduce it's period from about 54 days to 14 days, while maintaining a ...
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 ...
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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 ...
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0answers
51 views

Discrepancy between Launch Vehicle Performance website on Atlas V 551 with Juno

I was looking at the Juno space probe which was launched in August 2011 onboard an Atlas V 551. In particular I was looking at https://elvperf.ksc.nasa.gov/Pages/News.aspx and using the performance ...
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2answers
139 views

How, and How Well will Juno measure the effects of frame dragging? (GR effect due to Jupiter's mass & rotation)

This answer links to Spaceflight 101's One Week to Jupiter – NASA’s Juno Spacecraft en-route to Gas Giant after five-year Journey which says Also, Juno will put Einstein’s General Theory of ...
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 ...
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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, ...
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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) ...
3
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0answers
109 views

Has budgetary support for Juno been extended, or is it running out?

The Yahoo news article NASA’s Juno snapped another photo of Jupiter that looks like a watercolor painting is a reminder that Juno is generating plenty of data and beautiful images. The Juno ...
2
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1answer
232 views

Why would Juno's originally planned orbit lowering partially mitigate radiation damage?

I'm trying to understand where Juno will pick up most of the slow, cumulative radiation damage within it's orbit. Currently it is in the higher, 53 day orbit. The original plan was that tomorrow (...
2
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1answer
171 views

Juno RF power output

What is the RF Power Output from Juno into its Parabolic dish, and the RF radiated out from the dish and the eventual power received say at the dish in Canberra which obviously then would need to be ...
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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 ...
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?
6
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1answer
338 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 ...
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 ...
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3answers
721 views

Why does a spacecraft's attitude become stable when it rotates?

What is the logic behind spacecraft spinning to increase stability? How does angular momentum play a role in this?
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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 ...
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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?
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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 ...
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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 ...
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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
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 ...
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2answers
130 views

Juno possible retirement adjustment

Notice: I deeply apologize if I'm missing a Logical Issue to this Plan. Instead of ending Juno's mission in 2018 by deorbiting it into Jupiter why not follow these steps. Allow the amount of time ...
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1answer
54 views

Juno launch to aphelion

I would like to calculate the length of the semi-major axis of Juno's initial heliocentric ellipse from launch to aphelion based on the time from launch to aphelion. Do I use the full 394 days from ...
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1answer
139 views

How to know when JPL Horizons is updated with new Juno spacecraft trajectory?

I "watched" Juno's flyby of Jupiter using the simulation in the NASA's Eyes app on my laptop, and later saw the good news in this tweet. Now I want to do a "flyby in Python". Using the setup (shown ...
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4answers
662 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?
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1answer
618 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 ...
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0answers
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How slingshot is used to increase the speed of Juno [duplicate]

I have gone through the slingshot for the Juno with the earth. I have also seen the train and ball example as given by NASA. [http://solarsystem.nasa.gov/basics/grav/primer.php] But, I am still ...
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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 ...
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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 ...
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 ...
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 ...
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 ...
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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 ...
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 ...
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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 ...
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3answers
622 views

Has Juno now gone faster than - and braked harder than - any other human-made object ever?

Juno just passed its closest approach to Jupiter, going 58 km/s because it was so deep in Jupiter's gravity well. Ironically, it did this while retrofiring its engines, to slow down. That sounds ...
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 ...
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1answer
1k views

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. ...
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3answers
181 views

Juno to Jupiter Budget

Would the Juno program be more cost effective if the spacecraft took a direct flight to Jupiter rather than using gravitational pull from planets, which took nearly 5 years instead of say, 2 years? ...
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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 ...
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 ...
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2answers
330 views

How to understand this NASA animation of Juno's passes near Jupiter?

I don't understand! Rotating frame? I see Orion pass by around 00:30 to 00:36, that's a clue. Why the first two passes are on the same side (in this view) but the rest alternate? edit: This is ...