Temperature Plots on Mobile: are only available on devices 500px or wider. Try using your mobile device in landscape orientation.
Final Temp Plots. Applicable Blogs: Hot and Cold | Final Temperature? Plots are interactive: Hover/tap on traces to see (Launch+Day, TempKelvin) pairs. Use tools in upper right to zoom/screenshot.
From concept to blueprint, through years of extensive development and testing, a successful launch and deployment, carefully managed cooldown, precise mirror alignment and instrument calibration, and finally the stunning release of its first full-color images, Webb begins its science mission.
The release of Webb’s first images and spectra kicks off the beginning of Webb’s science operations, where astronomers around the world will have their chance to observe anything from objects within our solar system to the early universe using Webb’s four instruments.
The James Webb Space Telescope is the world's premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
Webb in 3d Solar System
About Where Is Webb
WhereIsWebb tracked and visually presented, on a constantly updated daily basis, the state of Webb from its launch (12/25/21) until its first science images were released (7/12/22). It gave the Webb audience a depth, breadth and frequency of information into Webb's status well beyond the mission norm. It tracked:
Webb's flight (speed, distance, arrival) to L2,
its state of deployment (with images, animations, links to current status blogs, press conferences, etc), in concert its partner page, the Webb Deployment Explorer which outlined the entire process and archived all status annotations.
its cool down to operational temperatures (with interactive temp plots),
the entire mirror alignment process,
the commissioning of its instruments and modes
the presentation of Webb's first science images
its location in our solar system in 3d (thanks to NASA Eyes)
This process is now complete but much can be learned from exploring this page and its companion page, the Webb Deployment Explorer.
For information on the design thinking, user feedback and statistics on WhereIsWebb's success see Webb Launch Rewind.
More Detail
During launch and commissioning, the page constantly updated in near realtime as Webb traveled, deployed, cooled to operating temperature and as instruments were turned on, tested and verified. An icon/thumbnail representing the most recently completed deployment/commissioning step for Webb was displayed on the timeline/schedule that indicates all the major deployment/commissiong phases. Below the timeline, Webb's current state was expanded with regularly updated status information, blog posts, tracker images etc as well a links to relevant media. This same state was highilighted in the sequence of all detailed states on the Webb Deployment Explorer. WhereIsWebb (via NASA Eyes) also provides users with a 3d model of Webb showing its location in our 3d solar system where users can also compare Webb to Hubble and other spacecraft in 3d.
What you see now is the final state of Webb as it entered 'Ongoing Science Operations Mode'. The temperatures displayed show that they have reached and are maintained at a narrow band steady state. You can explore the entire annotated deployment and commissioning process on the Webb Deployment Explorer.
The remainder of this page is written in the present tense matching the original documentation.
If you have any issues with the page, hold the CTRL or CMD key and hit the F5 key which will reload the page and should clear any issues. (cntl/cmd shift R works too).
Tracking
While Webb is in flight to L2, its journey is tracked numerically at the top of the page showing its progress in time, distance, speed, percentage of trip complete to L2. Below those numbers, is a timeline switchable between DAYS/DISTANCE since launch, a thumbnail of Webb's MOST RECENTLY COMPLETED deployment step marking its place in TIME or DISTANCE on its 30 day journey to L2 followed by details of the current deployment step shown with a larger image, info and links.
Once Webb has reached L2, this page will transition to tracking Webb's commissioning steps including the vital process of cooling to operating temperatures and mirror alignment, followed by instrument commissioning. At this point the top of the page will show a set of bellweather current daily temperature obsevations followed by plots of those temperatures.
Deployment Phases and Steps
The most recently completed (unless noted as "Status:Ongoing" ) deployment/commissioning step for Webb is displayed along a time/distance line that also indicates the major deployment/commisioning phases. A phase may have many steps. Note that the timing, duration and/or order of these phases and steps may change. This page shows the default/nominal timing and order. The phases mark the start and end of major groups of deployment steps. The most recently completed deployment/commissioning step is shown as an icon on the ltime/distance ine and is detailed below with a larger image and links. Deployment/commissioning phases and steps are shown on the line in a light blue overlay on screens large enough to display this info, otherwise hidden.
Explore ALL Deployment Steps
You can EXPLORE past and upcoming deployments on the way to L2 and through commissioning. The Deployment Explorer opens to the most recently completed (unless noted as "Status:Ongoing" ) deployment/commissioning step, all steps to the "left" (on the top thumbnail nav) are COMPLETED, all steps to the "right" (on the top thumbnail nav) are FUTURE.
Time vs Distance View
The graduated horizontal line tracks the progress of Webb on its journey to L2 orbit. It can be displayed in time view or as a percentage of the total distance travelled to reach L2 orbit. The display defaults to a TIME line. The units are days. We refer to deployment events in terms of launch + elapsed-time so this view is useful for tracking deployments and time progress. Webb enters its L2 orbit at approximately 29.5days on the timeline. In "distance" view, it shows the percentage of the total distance to Webb entering its L2 orbit. Note on smaller screens the labels are progressively simplified and/or removed.
Your last chosen view mode is stored in a temporary "session" (non-persistent) cookie. This cookie will last at most until you close your browser and then be deleted. NASA Privacy Policy.
Speed and Distance
The speed and distance numbers displayed track Webb's distance travelled from Earth to entry into its L2 orbit. The numbers are derived from precalculated flight dynamics data that models Webb's flight up to its entry into L2 orbit. The distance numbers displayed are the approximate distance travelled as opposed to altitude. All the speed and distance data is with respect to an Earth-centered coordinate system.
With much higher speeds early in the trip, Webb covers a large percentage of the distance to L2 orbit early in its trip. This can be seen by toggling the "time" vs "distance %" views on the "progress line". Webb's speed is at its peak while connected to the push of the launch vehicle. It begins to slow rapidly after separation as it coasts up hill climbing the gravity ridge from Earth to its orbit around L2. Note on the TIME view that Webb reaches the altitude of the moon in ~2.5 days (which is ~8% of the total trip time but ~25% of its trip distance). See the sections below on Distance to L2 and Arrival at L2 for more information on the distance travelled to L2.
Passing The Moon
As noted above, this page displays the "distance travelled" by Webb as opposed to its altitude from Earth. Webb launched on the sun-facing side of the Earth and travels on a slightly curved path so Webb's "distance travelled" is greater than its altitude. Webb passing the Moon's altitude is a good example of the difference, when Webb reached the altitude (a) of the Moon at a time of launch + ~2.5 days, Webb had already travelled a distance (d) greater than the moon's altitude.
Temperatures
This page displays 2 "hot side" and 2 "cold side" temperatures on each side of the sunshield to illustrate the incredible engineering and effectiveness of the sunshield. A set of bellwether instrument temperature observations are included that give a good indication of the temperature trends that drive commisioning activities.
Temperatures are updated once per day daily during Webb's cool down and then weekly through the end of commissiong once they are at operational levels (see blog: Final Temperature? ). In general, temperatures change slowly so this frequency is sufficient to give a snapshot of overall trends. Temperatures are rounded to the nearest whole number and displayed in the users choice of Farenheit or Celsius along with Kelvin in parentheses.
Distance to L2
L2 is approximately 1 million miles from Earth (932056 miles/1.5M km to be exact). But Webb never actually arrives at L2, it is travelling to enter an orbit around L2. Webb's L2 orbit is very large in size and it enters its orbit before it reaches the linear distance between Earth and L2. Webb's orbit around L2 is known as a halo orbit which, rather than a single path, is an orbit that periodically varies through a series of paths around L2.
Arrival at L2 Orbit
By design, the launch vehicle and Webb's trajectory put Webb on a path to an L2 orbit with only small inputs needed to refine it. As it separates from the upper stage of the launch vehicle, Webb is climbing the gravity ridge from Earth up into a halo orbit around L2. Once Webb is in its halo orbit it will be riding up and down and over and along the shallow saddle contour at L2. Read more about L2 in this blog entry.
To get the exact orbit needed, Webb's trajectory is fine tuned by a number of "burns" along the way. You can learn more about these Mid Course Correction (MCC) burns on the Deployment Explorer page. The final burn, MCC2, inserts Webb into the desired L2 halo orbit. The MCC2 burn is now planned for L+30 days. At the end of that burn we can say Webb is "In L2 Orbit" and so has "arrived at L2".
Therefore, this page, for purposes of calculations uses a distance to L2 orbit entry number ( and timing ) that is a sufficient distance and time after the MCC2 burn to say "Webb is in L2 Orbit". Once in L2 orbit, this page will no longer track distance, but will track temperatures. The spacecraft will continue to cool to operating temperatures and numerous tests and calibrations occur to ready it for operations and its first images over the months that follow.
Page Display Units
By default the page loads and displays distances in miles, temperatures in Fahrenheit, ie English units (also known as Imperial or USCS system units). If you wish to have the page load and display in kilometers and temperatures in Celsius, ie metric system units use the urls below to select your preferred units. We do not use persistent cookies; so these urls 'store' your units preference. Once chosen, bookmark the urls with your preferred units and use it instead of the default website link. NOTE: the page units toggle button English<>Metric now reloads the page with these urls.
The following sections discuss a few issues with using this page.
Page Display Units
By default the page loads and displays distances in miles, temperatures in Fahrenheit, ie English/US units (also known as Imperial or USCS system units). If you wish to have the page load and display in kilometers and temperatures in Celsius, ie metric system units use the urls below to select your preferred units. We do not use cookies; these urls 'store' your units preference. Once chosen, bookmark the urls with your preferred units and use it instead of the default website link. NOTE: the page units toggle button English<>Metric now reloads the page with these urls.
The graduated horizontal line on the display is a TIME line. The units are days. There are 30days on the timeline. Webb enters its L2 orbit at approimately 29.5days on the timeline. Note on smaller screens the labels are progressively removed. On portrait mobile screens of 300-600px wide only the units "days" is displayed.
About Temperature Observations
Temperatures are updated once per day during Webb's cool down and then weekly through the end of commissiong once they are at operational levels (see blog: Final Temperature? ). In general, temperatures change slowly so this frequency is sufficient to give a snapshot of overall trends. Temperatures are rounded to the nearest whole number and displayed in the users choice of Farenheit or Celsius along with Kelvin in parentheses.
Temperature control is a vital aspect of Webb's design, engineering and operations. Of the many temperature monitoring points on the observatory, this page displays 2 "hot side" and 2 "cold side" temperatures and a set of bellwether instrument temperatures that are a good indication of overall temperature status and trends.
Instrument Temperatures ( 1-5 )
The instruments are located within the ISIM: Integrated Science Instrument Module and the Fine Steering Mirror is located within the protrusion in the center of the primary mirror as shown in the location diagram. Each temperature sensor is located on the "bench" of the instrument which is the main structure that holds the instrument's optics and components. Instruments are labelled with the following numbers (note: these labels will pop up if you hover your mouse over the display):
The temperatures displayed on the hot side of the observatory are located on the sunshield structure and spacecraft bus. . The temperatures displayed on the cold side of the observatory are located on the primary mirror and instrument (ISIM) module radiator. They are labelled with the following letters (note: these labels will pop up if you hover your mouse over the display):
b) Spacecraft Equipment Panel Average Temperature (hot side: Spacecraft Bus)
c) Primary Mirror Average Temperature (cold side: Mirrors)
d) Instrument Radiator Temperature (cold side: ISIM)
+
Units
By default the page loads and displays distances in miles, temperatures in Fahrenheit, ie English/US units (also known as Imperial or USCS system units). If you wish to have the page load and display in kilometers and temperatures in Celsius, ie metric system units use the urls below to select your preferred units. We do not use cookies; these urls 'store' your units preference. Once chosen, bookmark the urls with your preferred units and use it instead of the default website link. NOTE: the page units toggle button English<>Metric now reloads the page with these urls.
The collected data for each WhereIsWebb temperature observation point is plotted with launch+day on the X axis. Plots/temperatures are updated daily during Webb's cool down and then weekly through the end of commissioning once Webb's temperatures are at operational levels (see blog: Final Temperature? ).
Plots are interactive: you can hover (tap on touch devices) to identify the name of the trace and actual data point values. Using the tools in the upper right of the plot you can zoom in and out, drag, and reset the view, as well as download a plot image as a PNG.
Data for the Hot/Cold side comparisons started a few days after launch. Instrument temperature tracking started at day 33.
Mobile/Small Devices: due to the minimum size needed for usability, plots are not available on devices narrower than ~500px which is most mobile phones in portrait orientation due to the layout width needed. Try landscape orientation on your mobile which is usually wide enough, however they are best experienced on a tablet or larger device.
Interactive Plot Features
Trace Identification : Data traces for each obeservation point can be identifed in a number of ways: by matching color/pattern with the legend to the right of the plots, by number/letter marked at the start of each trace and matching it to the letter in the legend (on small devices you may need to zoom in to see these clearly), by hovering over the traces' letter designation or the trace itself (tap on touch devices) and the trace name is shown in a pop up.
Data Values: data values can be seen for each point plotted by hovering over the traces (tap on touch devices), the trace name and values are displayed in a pop up message.
Zoom In/Out : Use the + or - buttons in upper right to zoom the plot over all. Use the magnifying glass to select a specfic part of the plot and zoom in. Use the "home" button to reset the plot to original state.
Panning : Use the arrow tool button in upper right to pan the plot. This is especially useful once you have zoomed in.
Reset the View :Use the "home" button to reset the plot to original state. NOTE: on some devices, you may have to reload the page to get the view to reset after zooming and panning.
Locating the Observation Points : this button will open a panel to identify the locations of the temperature observation points on the spacecraft.
EXPLORE WEBB and the Solar System in 3d
NASA Eyes allows you to manipulate a 3d Webb model in our 3d solar system. It loads with Webb in the center of the 'scene'. You can then manipulate Webb/scene. Beside basic 3d manipulation of the X, Y, and Z axes and zooming in and out, there are many other features that literally allow you to EXPLORE Webb and our solar system. Many of these are detailed below.
FEATURES:
Labelled Spacecraft : Above the Eyes panel is a button to pop-up a labelled spacecraft image to help you identify Webb's subsystems as you move around it in 3d.
Spin Webb/scene in 3d : Desktop- click/drag, Mobile/Touch- tap/drag. Keyboard: ROTATE X - A/D, ROTATE Y - Q/E, ROTATE Z - Z/C. Add SHIFT for faster speed.
Zoom Out - Get to know Webb's neighbors : See its relationship with the Earth, Moon and Sun.
Compare Webb's size to other objects like a school bus or Hubble: Use the 'Compare' link at bottom of the title/ID panel to cycle through a list of objects.
Align Webb with the Sun and turn off the fill lighting: Manipulate Webb/scene with the mirror/telescope side up and then finely align it such that the Sun is behind it. Then, turn off the artificial fill lights (lower right light bulb icon) and you will understand one of the key reasons why cameras for monitoring would not be helpful on Webb. It's completely in the dark on the mirror side of the sunshield.
Zoom way out and explore the solar system surrounding Webb. Click on any object to 'ID' it and double click to load it into the center of the scene to see it in 3d and manipulate it.
Use the search to find/jump to any number of objects in our solar system : Spacecraft, planets, moons, comets, asteroids and more. Just start typing and watch the autocomplete above the search to see matches. Click a match.
More Fun Explorations: The Eyes team recommends going into HD mode (clicking the 'HD' button) and then explore the amazing textures of Earth, Mars, the Moon, and Jupiter to name a few. NOTE: Earth’s image mosaic is built from actual live data images captured the day before via Suomi NPP’s VIIRS camera! Watch the ISS cruise over Earth in HD.
See other amazing NASA Eyes products : Explore the thousands of confirmed exoplanets we’ve discovered. Explore asteroids, the Earth to see all the climate change data, and the Perseverance Entry|Descent|Landing (EDL).
