Does Voyager 1 Have A Camera

Ian Regan • Apr 16, 2019

Voyager Wide-Bending Views of Jupiter

Terminal month marked the 40th anniversary of the historic Voyager one encounter with Jupiter in 1979. Voyager 1 was not the first robotic visitor to Jupiter; Pioneers 10 and 11 flew by the gas behemothic in 1973 and 1974. But while the Pioneers' primitive spin-browse photopolarimeters took very skillful, groundbreaking images of the planet, they couldn't compete with the Idiot box cameras of the Voyagers.

The cameras, while not at the forefront of technology in the belatedly-1970s, were even so a reliable and proven method of capturing images in deep infinite. They had a pedigree stretching dorsum to the early Mariner probes—non surprising, given that the Voyager program was essentially a continuation of Mariner (the ii Voyager probes were developed nether the moniker 'Mariner-Jupiter-Saturn').

Each Voyager carried a pair of TV cameras, mounted behind telescopes of differing focal length, giving the operators the choice of taking images spanning 0.4 degrees (the NAC or narrow-angle camera), or 3 degrees (the WAC or broad-angle camera). In traditional photographic terms, both systems are squarely in the telephoto category.

Most of the valuable photographic data came from the NAC, given the greater resolution it offered. Notwithstanding, the overlooked WAC had two principal roles: to provide context views of the highly localized NAC shots, while as well providing continuous photographic surveillance of global-scale features on Jupiter and its moons near the menstruum effectually closest approach.

Voyager 1

Jupiter is huge. On 17 February 1979, Voyager one was no longer able to fit the planet into a single frame of the narrow-angle camera, even though the spacecraft was nonetheless a staggering 11 million miles away.

The broad-angle photographic camera was similarly overwhelmed on 3 March 1979, when the planet was 1.4 1000000 miles distant.

Jupiter and Callisto from Voyager 1 This color composite of Jupiter was the final image captured by Voyager 1 earlier its broad-angle camera could no longer fit the whole of the planet inside its 3.2 degree field of view. Even so, due to pointing inaccuracies, nigh images that Voyager 1 acquired from this distance were truncated on one edge. Therefore, this is actually a mosaic of 2 sets of frames taken through orange, green, and violet filters, all taken on March 3, 1979, from a distance of ii.iii million km. Callisto is visible only off to the right of Jupiter'due south eastern limb, while the Smashing Red Spot and a large white oval dominate the southern hemisphere. *Image: NASA / JPL / Ian Regan*

All Voyager images of Jupiter captured on approach were usually taken with the NAC, and evidence a about fully illuminated globe, with the morning terminator visible merely shy of the planet's unlit, western limb. As Voyager 1 grew closer to the planet, its trajectory gave its cameras a view of a fully illuminated Jupiter. On 2 March, the phase angle dwindled to every bit fiddling every bit 0.ii degrees, analogous to a typical full Moon every bit seen from Earth.

From that indicate onward, with closest approach just a few days away, Jupiter presented a markedly different confront to the spacecraft—one where the nighttime terminator now became visible on the eastern extent of the gaseous sphere.

I wondered if it would exist possible to reconstruct this seldom seen face up of Jupiter: a global portrait with the night terminator hugging the eastern limb. At this distance, narrow-angle imagery was all but useless for this purpose and data gathered by the lesser-celebrated wide-bending camera offered the just possibility.

For Voyager one, the broad-bending images captured over a 24-hour menses prior to closest approach were not sufficient, both in spatial and spectral coverage, to compile a representative colour mosaic of the planet. A great quantity of frames were trained (understandably) upon the Great Ruby-red Spot, leaving rather meager coverage of everything else.

However, I plant information technology possible to combine information collected through the orange, light-green, bluish, and occasionally violet, filters to produce the following mosaic of Jupiter's western limb, as seen past Voyager on the evening of March 4th, 1979:

Io above Jupiter The innermost Galliean satellite, Io, coasts higher up the russet cloud decks of Jupiter. This Voyager one mosaic principally consists of three color composites made of orange-, dark-green-, and blue-filtered images, all taken with the wide-bending photographic camera on 4 March 1979. Gaps in coverage were filled by other 3-filter composites taken earlier or subsequently the same day. North is to the right. Planet-spacecraft distance was some 1 million km. *Image: NASA / JPL / Ian Regan*

Io above Jupiter with shadow below The innermost Galliean satellite, Io, coasts above the russet cloud decks of Jupiter, marking Jupiter with its shadow. This Voyager 1 mosaic principally consists of iii color composites made of orangish-, green-, and blueish-filtered images, all taken with the wide-bending photographic camera on 4 March 1979. Gaps in coverage were filled by other 3-filter composites taken before or later the same twenty-four hours. North is to the correct. Planet-spacecraft distance was some 1 one thousand thousand km. *Image: NASA / JPL / Ian Regan*

Io can be seen transiting the planet, as the Smashing Reddish Spot comes into view. Given that the iii principle WAC colour composites used were captured at 17:xi, 21:21, and 21:37 (all times UTC), the view is somewhat of a Frankenstein creation, equally Jupiter'southward rapid rotation ensures that atmospheric features seen here at different latitudes are non shown in proper relation to 1 some other. Despite this drawback, this mosaic gives a very effective if somewhat illusory impression of the face that Jupiter presented to Voyager 1, merely 14 hours earlier closest approach.

Io transiting Jupiter's equatorial zone Voyager ane took the images for this blended through orange, light-green, and bluish filters on 4 March 1979 at 21:37 UTC. It was 999,000 kilometers from Jupiter at the time. *Image: NASA / JPL / Ian Regan*

Brown barge — Brown clomp A brown barge in Jupiter'southward north equatorial belt as seen by Voyager 1 at 23:29 on 4 March 1979 from a distance of 889,000 km. Three photos taken through orange, green, and blue filters were combined and adjusted to appear approximately natural color. *Image: NASA / JPL / Ian Regan*

Great Red Spot and white ovals from Voyager 1 — Dandy Red Spot and white ovals from Voyager 1 Voyager 1 took the images for this composite through orangish, green, and bluish filters on iv March 1979 at 17:11 UTC. It was 1,254,000 kilometers from Jupiter at the time. *Image: NASA / JPL / Ian Regan*

Jupiter belts and zones This Voyager 1 view spans both of Jupiter's orange-tinted equatorial belts and includes a portion of the loftier northern latitudes. Images composing it were taken through orange, greenish, and blueish filters from a distance of 1,302,000 kilometers. *Image: NASA / JPL / Ian Regan*

Voyager 2

Sixteen months later, the second Voyager (wielding a Television set camera with marginally greater sensitivity), focused on the Jovian system.

Callisto's shadow on Jupiter This was one of the concluding wide-angle views of Jupiter that Voyager 2 snapped before the planet became likewise large to exist photographed in a single frame. Although Jupiter would have fit in one view, the Voyager scan platform did non always achieve perfect pointing, so in this blended Jupiter is truncated where it vicious off the edge of the detector. The fuzzy nighttime spot is the shadow of Jupiter's outermost big moon, Callisto. Voyager 2 took the photos for this blended through orange, green, and violet filters on eight July 1979 from a distance of 2.17 million kilometers. *Prototype: NASA / JPL / Ian Regan*

In the evening of eight July 1979, a mere 25 hours before closest arroyo, Voyager 2's WAC captured a more comprehensive array of images of Jupiter than its twin, assuasive a full globe portrait of the planet to be equanimous, from vi 3-filter colour composites (either OGB or OGV).

Ganymede and Jupiter Global Voyager 2 Mosaic — Ganymede and Jupiter Global Voyager ii Mosaic The images for this blended were taken over a menses of four hours on viii July 1979 through orangish, light-green, and blue or violet filters. Considering of the long time span and Jupiter's rapid (10-hour) rotation, the deject positions don't represent any real instantaneous view of Jupiter. Ganymede'due south shadow falls on the disk of Jupiter. Ganymede was actually much farther from Jupiter as seen by Voyager 2 during this ascertainment; the altitude betwixt the two worlds has been reduced for artful expediency. Voyage 2 was about ane.5 million kilometers away from Jupiter during this ascertainment, only only 430,000 kilometers from Ganymede, which is why Ganymede appears so much larger than its shadow. *Image: NASA / JPL / Ian Regan*

Once more, these observations spanned a non-trivial time period (from 18:32 to 22:35 UTC), so the relative longitudinal positions of various cloud features cannot exist trusted.

Equally an added bonus, the shadow of Ganymede was captured crossing the confront of Jupiter; it is shown here equally seen by the WAC at xx:04 hrs. In fact, afterwards these images were taken, Voyager 2 turned its suite of instruments toward the moon itself, capturing many images through both camera systems. A wide-angle color composite of Ganymede, taken as context for the higher resolution mosaics, has been added to the Jupiter mosaic to complete this panoramic vista.

Near-global high-resolution color view of Ganymede from Voyager 2 This high-resolution colour mosaic of the anti-Jovian hemisphere of Ganymede was created using orange, blue and violet images (in the RGB channels respectively) from Voyager 2 at a resolution of 2 kilometers per pixel. *Image: NASA / JPL / Constantine Thomas*

Ganymede's shadow The shadow of Ganymede transverses the Jovian cloud decks. Voyager 2 took the photos for this blended with its wide-angle camera through orangish, green, and bluish filters at 18:32 on viii July 1979 from a altitude of 1.53 million km. *Image: NASA / JPL / Ian Regan*

Equatorial anticyclone on Jupiter Voyager two looked at the region eastward of the Great Red Spot to take the photos for this blended through orange, green, and violet filters at 21:40 on 8 July 1979 from a distance of 1.iv one thousand thousand km. *Image: NASA / JPL / Ian Regan*

Great Red Spot and a white oval from Voyager 2 — Great Red Spot and a white oval from Voyager ii The Great Red Spot moves toward the dusk terminator in this Voyager 2 view from a distance of 1.25 million km at 22:57 UTC on viii July 1979. Images taken through orange, green, and blue filters were combined to create this color view. *Image: NASA / JPL / Ian Regan*

While later emissaries to Jupiter, nigh notably Cassini and New Horizons, captured views of Jupiter from this particular bending, these unique Voyager perspectives have been buried in archived information until at present. Long live the Voyagers!