Ralph (New Horizons)

Last updated
Composite image from Ralph-MVIC of Jupiter PIA10098 Atmospheric Structure.jpg
Composite image from Ralph-MVIC of Jupiter
Ralph's MVIC-channel image of Jupiter's moon Io PIA10249.jpg
Ralph's MVIC-channel image of Jupiter's moon Io

Ralph is a science instrument aboard the robotic New Horizons spacecraft, which was launched in 2006. [1] Ralph is a visible and infrared imager and spectrometer to provide maps of relevant astronomical targets based on data from that hardware. [1] Ralph has two major subinstruments, LEISA and MVIC. [2] MVIC stands for Multispectral Visible Imaging Camera and is a color imaging device, while LEISA originally stood for Linear Etalon Imaging Spectral Array and is an infrared imaging spectrometer for spaceflight. [2] LEISA observes 250 discrete wavelengths of infrared light from 1.25 to 2.5 micrometers. [3] MVIC is a pushbroom scanner type of design with seven channels, including red, blue, near-infrared (NIR), and methane. [4]

Contents

Overview

Ralph is one of seven major instruments aboard New Horizons which was launched in 2006 and flew by the dwarf planet Pluto in 2015. [5] [6]

At Pluto, Ralph enables the observation of many aspects including: [7]

Ralph and Alice were used to characterize the atmosphere of Pluto in 2015. [8] Ralph was previously used to observe the planet Jupiter and its moons in 2006 and in 2007 when it flew-by en route out of the Solar System and past Pluto. [9] [10] Observations of Jupiter were taken with Ralph in February 2007, when New Horizons was about 6 million kilometers (nearly 4 million miles) from the giant. [10]

Ralph took color images of Arrokoth during the New Horizons flyby on January 1, 2019. [11] Ralph, in conjunction with the LORRI telescope, was used to make a digital elevation map of the body.

A version of Ralph is carried on Lucy, which is visiting six Jupiter trojans and an asteroid in the 2020s. [12] The developers of that spacecraft noted in particular Ralph's ability to observe visible and infrared light by splitting the light stream, and then analyze two spectrums of light at the same time. [12]

Naming

Ralph New Horizons - Ralph.png
Ralph

Ralph is named after a character in the 1950s television show The Honeymooners , [13] along with another New Horizons instrument, Alice. [14]

LEISA's acronym was retitled from Linear Etalon Imaging Spectral Array to Lisa Hardaway Infrared Mapping Spectrometer by NASA in June 2017, after Ralph's program manager. [15] Lisa Hardaway was an aerospace engineer and New Horizons Ralph instrument program manager who died in January 2017 at the age of 50. [16] Hardaway was honored with Engineer of the Year for 2015–2016 by the American Institute of Aeronautics and Astronautics (Rocky Mountain Section) and Women in Aerospace organization awarded her a leadership award in 2015. [17] In the summer of 2017, NASA renamed the LEISA channel in her honor. [18]

Lisa made incredible contributions to New Horizons and our success in exploring Pluto, and we wanted to celebrate those contributions in a special way by dedicating the LEISA spectrometer in her honor.

New Horizons principal investigator [18]

Methane observations

An example of Ralph's abilities is shown by this detection of methane on the surface of Pluto (left), overlaid on an image from LORRI on the right:

Ralph methane detections (left) overlaid onto a LORRI image of dwarf planet Pluto (right) NH-Pluto-MethaneIce-20150924.jpg
Ralph methane detections (left) overlaid onto a LORRI image of dwarf planet Pluto (right)
LEISA channel data, showing its lower definition infrared image of Pluto but with recorded infrared spectra of the dwarf planet in false color. Two infrared spectra are shown, from the outlined regions in the global map to the left. 1 Micron is 1000 nm, and visible light is below 1 Micron. NH-Pluto-MethaneIce-20150715.png
LEISA channel data, showing its lower definition infrared image of Pluto but with recorded infrared spectra of the dwarf planet in false color. Two infrared spectra are shown, from the outlined regions in the global map to the left. 1 Micron is 1000 nm, and visible light is below 1 Micron.

In 2018 it was announced, based on New Horizons high resolution data, that some of the plains of Pluto have dunes made of methane ice granules. [19] The dunes are thought to have been formed by the blowing winds of Pluto, which are not as dense as those of Earth, and were compared to Dunes elsewhere in the Solar System such as on Saturn's moon Titan. [20]

Specifications

Water ice identified on Pluto with Ralph spectral signatures of water ice from LEISA noted in blue on top of MVIC imaging NH-Pluto-WaterIceDetected-BlueRegions-Released-20151008.jpg
Water ice identified on Pluto with Ralph spectral signatures of water ice from LEISA noted in blue on top of MVIC imaging
This extremely low-light image is a view of the dark side of Pluto's moon Charon, lit by starlight and Plutoshine. Ralph-MVIC channel data PIA11708 - Charon in 'Plutoshine'.jpg
This extremely low-light image is a view of the dark side of Pluto's moon Charon, lit by starlight and Plutoshine. Ralph-MVIC channel data
Arrokoth image taken by Ralph-MVIC (January 2, 2019 release) First color image of Ultima Thule (MVIC crop).png
Arrokoth image taken by Ralph-MVIC (January 2, 2019 release)

Specifications: [21]

The one telescope feeds light to both LEISA and MVIC channels, with light split by a dichroic beamsplitter. [21] [22]

MVIC has seven CCDs that are wide but short, utilizing time-delay integration to read the imaging area. [23] These channels have a resolution of 5024×32 pixels, with the larger direction providing the swath of the image. [23] There are seven channels, with 6 used for time delay integration imaging and the seventh with an array of 5024×128 for navigation framing. [23] MVIC has a field of view that is 5.8 degrees wide [23] The framing channel, with 5024×128 pixel size, is panchromatic and a field of view of 5.7 degrees × 0.15 degrees. [24] Unlike the other six channels, it can stare at one target and take an image. [25] The purpose of this channel is to support optical navigation. [22] The Navigation channel is a Frame array that operates as a single frame, rather than the other channels which generate an image by time delay integration. [25]

MVIC Bands: [23] There are six channels that use Time Delay Integration and another that takes a frame and is for navigation. [22]

LEISA achieved its highest resolution data of Pluto of about 3 km/pixel at New Horizon's closest approach to Pluto on July 14, 2015, when it was 47,000 km distant. [26]

Images

During the flyby of Pluto on July 14, 2015, Ralph was able to collect data on Pluto and its moons yielding various image results. In addition, the MVIC color channels were often the source of color on the otherwise panchromatic LORRI images.

This image of Pluto from July 2015 flyby includes Ralph-MVIC red, blue, and NIR color data. Nh-pluto crop.png
This image of Pluto from July 2015 flyby includes Ralph-MVIC red, blue, and NIR color data.
Ralph-MVIC view's a 250 miles (400 kilometers) section of Pluto on July 14, 2015 Pluto's Heart - Like a Cosmic Lava Lamp.jpg
Ralph-MVIC view's a 250 miles (400 kilometers) section of Pluto on July 14, 2015
Attempted natural color view using only data from MVIC channel Pluto in True Color - High-Res.jpg
Attempted natural color view using only data from MVIC channel
An example of an image from LORRI, a view of Pluto's terrain from its 2015 flyby of the dwarf planet with Ralph-MVIC data from Red, Blue, and Near IR channels. This image is about 330 miles (530 kilometers) across "Snakeskin" Terrain on Pluto.jpg
An example of an image from LORRI, a view of Pluto's terrain from its 2015 flyby of the dwarf planet with Ralph-MVIC data from Red, Blue, and Near IR channels. This image is about 330 miles (530 kilometers) across

486958 Arrokoth

UltimaThule-ColorVariation-20190318 (cropped).png
UltimaThule-MVIC-color-20190318.jpg
UltimaThule-MVIC-20190318 (cropped).png
Ralph-MVIC color and spectral images of Arrokoth, showing subtle color variations across its surface. The image on the right is the same MVIC color image superimposed on the higher resolution black and white LORRI image. [lower-alpha 1]

See also

Notes

  1. Composite of black and while and color photographs taken respectively by the LORRI and MVIC instruments aboard New Horizons on 1 January 2019. [30]

Related Research Articles

<span class="mw-page-title-main">W. M. Keck Observatory</span> Astronomical observatory in Hawaii

The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have 10 m (33 ft) aperture primary mirrors, and when completed in 1993 and 1996 were the largest optical reflecting telescopes in the world. They are currently the 3rd and 4th largest.

<i>New Horizons</i> NASA probe that visited Pluto and Kuiper belt object 486958 Arrokoth

New Horizons is an interplanetary space probe launched as a part of NASA's New Frontiers program. Engineered by the Johns Hopkins University Applied Physics Laboratory (APL) and the Southwest Research Institute (SwRI), with a team led by Alan Stern, the spacecraft was launched in 2006 with the primary mission to perform a flyby study of the Pluto system in 2015, and a secondary mission to fly by and study one or more other Kuiper belt objects (KBOs) in the decade to follow, which became a mission to 486958 Arrokoth. It is the fifth space probe to achieve the escape velocity needed to leave the Solar System.

<span class="mw-page-title-main">132524 APL</span> Asteroid visited by New Horizons

132524 APL, provisional designation 2002 JF56, is a small background asteroid in the intermediate asteroid belt. It was discovered by Lincoln Near-Earth Asteroid Research in May 2002, and imaged by the New Horizons space probe on its flyby in June 2006, when it was passing through the asteroid belt. The stony S-type asteroid measures approximately 2.5 kilometers (1.6 miles) in diameter.

<span class="mw-page-title-main">Imaging spectrometer</span>

An imaging spectrometer is an instrument used in hyperspectral imaging and imaging spectroscopy to acquire a spectrally-resolved image of an object or scene, often referred to as a datacube due to the three-dimensional representation of the data. Two axes of the image correspond to vertical and horizontal distance and the third to wavelength. The principle of operation is the same as that of the simple spectrometer, but special care is taken to avoid optical aberrations for better image quality.

<span class="mw-page-title-main">Wide Field Camera 3</span> Astronomical camera on the Hubble Space Telescope

The Wide Field Camera 3 (WFC3) is the Hubble Space Telescope's last and most technologically advanced instrument to take images in the visible spectrum. It was installed as a replacement for the Wide Field and Planetary Camera 2 during the first spacewalk of Space Shuttle mission STS-125 on May 14, 2009.

JunoCam is the visible-light camera/telescope onboard NASA's Juno spacecraft currently orbiting Jupiter. The camera is operated by the JunoCam Digital Electronics Assembly (JDEA). Both the camera and JDEA were built by Malin Space Science Systems. JunoCam takes a swath of imaging as the spacecraft rotates; the camera is fixed to the spacecraft, so as it rotates, it gets one sweep of observation. It has a field of view of 58 degrees with four filters.

<span class="mw-page-title-main">ADEOS I</span> Japanese Earth observation satellite

ADEOS I was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori means "green". The mission ended in July 1997 after the satellite sustained structural damage to the solar panel. Its successor, ADEOS II, was launched in 2002. Like the first mission, it ended after less than a year, also following solar panel malfunctions.

<span class="mw-page-title-main">Astronomical filter</span> Telescope accessory used to improve details of viewed objects

An astronomical filter is a telescope accessory consisting of an optical filter used by amateur astronomers to simply improve the details and contrast of celestial objects, either for viewing or for photography. Research astronomers, on the other hand, use various band-pass filters for photometry on telescopes, in order to obtain measurements which reveal objects' astrophysical properties, such as stellar classification and placement of a celestial body on its Wien curve.

<span class="mw-page-title-main">Jovian Infrared Auroral Mapper</span>

Jovian Infrared Auroral Mapper (JIRAM) is an instrument on the Juno spacecraft in orbit of the planet Jupiter. It is an image spectrometer and was contributed by Italy. Similar instruments are on ESA Rosetta, Venus Express, and Cassini-Huygens missions. The primary goal of JIRAM is to probe the upper layers of Jupiter's atmosphere down to pressures of 5–7 bars at infrared wavelengths in the 2–5 μm interval using an imager and a spectrometer. The Jupiter's atmosphere and auroral regions are targeted for study. In particular it has been designed to study the dynamics and chemistry in the atmosphere, perhaps determining the how Jovian hot spots form.

<span class="mw-page-title-main">Sentinel-5 Precursor</span> Earth observation satellite

Sentinel-5 Precursor (Sentinel-5P) is an Earth observation satellite developed by ESA as part of the Copernicus Programme to close the gap in continuity of observations between Envisat and Sentinel-5.

<i>Lucy</i> (spacecraft) NASA mission to fly by eight asteroids

Lucy is a NASA space probe on a twelve-year journey to eight different asteroids. It is slated to visit two main belt asteroids as well as six Jupiter trojans – asteroids that share Jupiter's orbit around the Sun, orbiting either ahead of or behind the planet. All target encounters will be flyby encounters. The Lucy spacecraft is the centerpiece of a US$981 million mission. It was launched on 16 October 2021.

<span class="mw-page-title-main">Mid-Infrared Instrument</span> Camera and spectrometer on the James Webb Space Telescope

MIRI, or the Mid-Infrared Instrument, is an instrument on the James Webb Space Telescope. MIRI is a camera and a spectrograph that observes mid to long infrared radiation from 5 to 28 microns. It also has coronagraphs, especially for observing exoplanets. Whereas most of the other instruments on Webb can see from the start of near infrared, or even as short as orange visible light, MIRI can see longer wavelength light.

UVS (<i>Juno</i>) Spectrometer instrument on the Juno orbiter

UVS, known as the Ultraviolet Spectrograph or Ultraviolet Imaging Spectrometer is the name of an instrument on the Juno orbiter for Jupiter. The instrument is an imaging spectrometer that observes the ultraviolet range of light wavelengths, which is shorter wavelengths than visible light but longer than X-rays. Specifically, it is focused on making remote observations of the aurora, detecting the emissions of gases such as hydrogen in the far-ultraviolet. UVS will observes light from as short a wavelength as 70 nm up to 200 nm, which is in the extreme and far ultraviolet range of light. The source of aurora emissions of Jupiter is one of the goals of the instrument. UVS is one of many instruments on Juno, but it is in particular designed to operate in conjunction with JADE, which observes high-energy particles. With both instruments operating together, both the UV emissions and high-energy particles at the same place and time can be synthesized. This supports the Goal of determining the source of the Jovian magnetic field. There has been a problem understanding the Jovian aurora, ever since Chandra determined X-rays were coming not from, as it was thought Io's orbit but from the polar regions. Every 45 minutes an X-ray hot-spot pulsates, corroborated by a similar previous detection in radio emissions by Galileo and Cassini spacecraft. One theory is that its related to the solar wind. The mystery is not that there are X-rays coming Jupiter, which has been known for decades, as detected by previous X-ray observatories, but rather why with the Chandra observation, that pulse was coming from the north polar region.

<span class="mw-page-title-main">Cathy Olkin</span> American planetary scientist

Cathy Olkin is a planetary scientist at the Southwest Research Institute, focusing on the outer Solar System. She is deputy principal investigator for NASA's Lucy mission examining the Trojan asteroids around Jupiter, which launched in 2021 and will fly past its targets between 2025 and 2033.

Lisa Hardaway (1966–2017) was an American aerospace engineer and program manager for an instrument on the New Horizons spacecraft to Pluto and Beyond. Among her awards, she was named Engineer of the Year for 2015–2016 by the Colorado American Institute of Aeronautics and Astronautics.

Nadir and Occultation for MArs Discovery (NOMAD) is a 3-channel spectrometer on board the ExoMars Trace Gas Orbiter (TGO) launched to Mars orbit on 14 March 2016.

<span class="mw-page-title-main">Long Range Reconnaissance Imager</span> Telescope aboard the New Horizons spacecraft for imaging

Long Range Reconnaissance Imager (LORRI) is a telescope aboard the New Horizons spacecraft for imaging. LORRI has been used to image Jupiter, its moons, Pluto and its moons, and Arrokoth since its launch in 2006. LORRI is a reflecting telescope of Ritchey-Chrétien design, and it has a main mirror diameter of 208 mm across. LORRI has a narrow field of view, less than a third of a degree. Images are taken with a CCD capturing data with 1024 × 1024 pixels. LORRI is a telescopic panchromatic camera integrated with the New Horizons spacecraft, and it is one of seven major science instruments on the probe. LORRI does not have any moving parts and is pointed by moving the entire New Horizons spacecraft.

<span class="mw-page-title-main">Pluto Energetic Particle Spectrometer Science Investigation</span> Instrument on the New Horizons space probe

Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI), is an instrument on the New Horizons space probe to Pluto and beyond, it is designed to measure ions and electrons. Specifically, it is focused on measuring ions escaping from the atmosphere of Pluto during the 2015 flyby. It is one of seven major scientific instruments aboard the spacecraft. The spacecraft was launched in 2006, flew by Jupiter the following year, and went onto flyby Pluto in 2015 where PEPSSI was able to record and transmit back to Earth its planned data collections.

<span class="mw-page-title-main">Alice (spacecraft instrument)</span>

Alice is an ultraviolet imaging spectrometer, with one used on the New Horizons spacecraft, and another on the Rosetta spacecraft. Alice is a small telescope with a spectrograph and a special detector with 32 pixels each with 1024 spectral channels detecting ultraviolet light. The instrument has a mass of 4.4 kg and draws 4.4 watts of power. Its primary role is to determine the relative concentrations of various elements and isotopes in Pluto's atmosphere.

References

  1. 1 2 Talbert, Tricia (2015-03-25). "Spacecraft and Instruments". NASA. Retrieved 2018-10-11.
  2. 1 2 Weaver, et al – Overview of the New Horizons Science Payload
  3. FEATURED IMAGE: A Look From LEISA
  4. Stockton, Nick. "The Camera Adding Color to Your Pluto Pics Has Bigger Plans". Wired.
  5. "Pluto | New Horizons | Exploring the Planets | National Air and Space Museum". airandspace.si.edu. Retrieved 2018-10-11.
  6. "New Horizons' Dramatic Journey to Pluto Revealed in New Book". Space.com. Retrieved 2018-10-11.
  7. "Meet Ralph, the New Horizons Camera Bringing Pluto into Sharp Focus – SpaceNews.com". SpaceNews.com. 2015-07-11. Retrieved 2018-10-11.
  8. "New Horizons begins Pluto observations ahead of July flyby – NASASpaceFlight.com". www.nasaspaceflight.com. 19 January 2015. Retrieved 2018-10-11.
  9. "NASA – Jupiter Ahoy!". www.nasa.gov. George Diller : KSC. Retrieved 2018-10-11.{{cite web}}: CS1 maint: others (link)
  10. 1 2 "NASA – A Look From LEISA". www.nasa.gov. Retrieved 2018-10-11.
  11. New Horizons explores the Kuiper Belt
  12. 1 2 "Aboard the first spacecraft to the trojan asteroids—NASA Ralph's next adventure". phys.org. Retrieved 2018-12-19.
  13. "Honeymooners, The". Encyclopedia of Television. The Museum of Broadcast Communications. Archived from the original on 2014-10-06. Retrieved 2018-10-11.
  14. Gipson, Lillian (2017-06-23). "NASA's New Horizons Mission Honors Memory of Engineer Lisa Hardaway". NASA. Retrieved 2018-10-11.
  15. Gipson, Lillian, ed. (June 23, 2017). "NASA's New Horizons Mission Honors Memory of Engineer Lisa Hardaway". NASA. Retrieved June 27, 2017.
  16. "Lisa Hardaway, pioneering Ball Aerospace engineer in Boulder, dies at 50". 26 January 2017.
  17. "Lisa Hardaway, pioneering Ball Aerospace engineer in Boulder, dies at 50". Daily Camera. 26 January 2017. Retrieved 2018-12-19.
  18. 1 2 Gipson, Lillian (2017-06-23). "NASA's New Horizons Mission Honors Memory of Engineer Lisa Hardaway". NASA. Retrieved 2018-12-19.
  19. Koren, Marina (2018-05-31). "What Pluto and California Have in Common". The Atlantic. Retrieved 2018-10-18.
  20. "A brief history of Pluto". Nature. 439 (7075): 378–9. January 2006. Bibcode:2006Natur.439..378.. doi: 10.1038/439378b . ISSN   0028-0836. PMID   16437073.
  21. 1 2 Ralph: A Visible/Infrared Imager for the New Horizons Pluto/Kuiper Belt Mission
  22. 1 2 3 4 Ralph: A Visible/Infrared Imager for the New Horizons Pluto/Kuiper Belt Mission
  23. 1 2 3 4 5 "Meet Ralph, the New Horizons probe imaging tool responsible for Pluto photos". DPReview. Retrieved 2018-10-18.
  24. "PDS: Instrument Information". Planetary Data System. NASA. Retrieved 2018-12-19.
  25. 1 2 "PDS: Instrument Information".
  26. "Highest Spatial Resolution New Horizons Leisa Spectral-Imaging Scan of Pluto"
  27. Talbert, Tricia (2015-10-15). "New Horizons Publishes First Research Paper in 'Science'". NASA. Retrieved 2018-10-24.
  28. "Catalog Page for PIA20726". photojournal.jpl.nasa.gov. Retrieved 2018-10-24.
  29. "New Horizons". pluto.jhuapl.edu. Retrieved 2018-10-24.
  30. Johns Hopkins University Applied Physics Laboratory (1 January 2019). "First color image of Ultima Thule". Applied Physics Laboratory . Archived from the original on 2 January 2019. Retrieved 2 January 2019.