Members Can Post Anonymously On This Site
Work continues to deploy Juice RIME antenna
-
Similar Topics
-
By NASA
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
A crane lowers the steel reflector framework for Deep Space Station 23 into position Dec. 18 on a 65-foot-high (20-meter) platform above the antenna’s pedestal that will steer the reflector. Panels will be affixed to the structure create a curved surface to collect radio frequency signals.NASA/JPL-Caltech After the steel framework of the Deep Space Station 23 reflector dish was lowered into place on Dec. 18, a crew installed the quadripod, a four-legged support structure that will direct radio frequency signals from deep space that bounce off the main reflector into the antenna’s receiver.NASA/JPL-Caltech Deep Space Station 23’s 133-ton reflector dish was recently installed, marking a key step in strengthening NASA’s Deep Space Network.
NASA’s Deep Space Network, an array of giant radio antennas, allows agency missions to track, send commands to, and receive scientific data from spacecraft venturing to the Moon and beyond. NASA is adding a new antenna, bringing the total to 15, to support increased demand for the world’s largest and most sensitive radio frequency telecommunication system.
Installation of the latest antenna took place on Dec. 18, when teams at NASA’s Goldstone Deep Space Communications Complex near Barstow, California, installed the metal reflector framework for Deep Space Station 23, a multifrequency beam-waveguide antenna. When operational in 2026, Deep Space Station 23 will receive transmissions from missions such as Perseverance, Psyche, Europa Clipper, Voyager 1, and a growing fleet of future human and robotic spacecraft in deep space.
“This addition to the Deep Space Network represents a crucial communication upgrade for the agency,” said Kevin Coggins, deputy associate administrator of NASA’s SCaN (Space Communications and Navigation) program. “The communications infrastructure has been in continuous operation since its creation in 1963, and with this upgrade we are ensuring NASA is ready to support the growing number of missions exploring the Moon, Mars, and beyond.”
This time-lapse video shows the entire day of construction activities for the Deep Space Station 23 antenna at the NASA Deep Space Network’s Goldstone Space Communications Complex near Barstow, California, on Dec. 18. NASA/JPL-Caltech Construction of the new antenna has been under way for more than four years, and during the installation, teams used a crawler crane to lower the 133-ton metal skeleton of the 112-foot-wide (34-meter-wide) parabolic reflector before it was bolted to a 65-foot-high (20-meter-high) alidade, a platform above the antenna’s pedestal that will steer the reflector during operations.
“One of the biggest challenges facing us during the lift was to ensure that 40 bolt-holes were perfectly aligned between the structure and alidade,” said Germaine Aziz, systems engineer, Deep Space Network Aperture Enhancement Program of NASA’s Jet Propulsion Laboratory in Southern California. “This required a meticulous emphasis on alignment prior to the lift to guarantee everything went smoothly on the day.”
Following the main lift, engineers carried out a lighter lift to place a quadripod, a four-legged support structure weighing 16 1/2 tons, onto the center of the upward-facing reflector. The quadripod features a curved subreflector that will direct radio frequency signals from deep space that bounce off the main reflector into the antenna’s pedestal, where the antenna’s receivers are housed.
In the early morning of Dec. 18, a crane looms over the 112-foot-wide (34-meter-wide) steel framework for Deep Space Station 23 reflector dish, which will soon be lowered into position on the antenna’s base structure.NASA/JPL-Caltech Engineers will now work to fit panels onto the steel skeleton to create a curved surface to reflect radio frequency signals. Once complete, Deep Space Station 23 will be the fifth of six new beam-waveguide antennas to join the network, following Deep Space Station 53, which was added at the Deep Space Network’s Madrid complex in 2022.
“With the Deep Space Network, we are able to explore the Martian landscape with our rovers, see the James Webb Space Telescope’s stunning cosmic observations, and so much more,” said Laurie Leshin, director of JPL. “The network enables over 40 deep space missions, including the farthest human-made objects in the universe, Voyager 1 and 2. With upgrades like these, the network will continue to support humanity’s exploration of our solar system and beyond, enabling groundbreaking science and discovery far into the future.”
NASA’s Deep Space Network is managed by JPL, with the oversight of NASA’s SCaN Program. More than 100 NASA and non-NASA missions rely on the Deep Space Network and Near Space Network, including supporting astronauts aboard the International Space Station and future Artemis missions, monitoring Earth’s weather and the effects of climate change, supporting lunar exploration, and uncovering the solar system and beyond.
For more information about the Deep Space Network, visit:
https://www.nasa.gov/communicating-with-missions/dsn
News Media Contact
Ian J. O’Neill
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-2649
ian.j.oneill@jpl.nasa.gov
2024-179
Share
Details
Last Updated Dec 20, 2024 Related Terms
Deep Space Network Jet Propulsion Laboratory Space Communications & Navigation Program Space Operations Mission Directorate Explore More
4 min read Lab Work Digs Into Gullies Seen on Giant Asteroid Vesta by NASA’s Dawn
Article 8 hours ago 5 min read Avalanches, Icy Explosions, and Dunes: NASA Is Tracking New Year on Mars
Article 9 hours ago 8 min read NASA’s Kennedy Space Center Looks to Thrive in 2025
Article 2 days ago Keep Exploring Discover Related Topics
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
By NASA
NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Known as flow formations, these channels could be etched on bodies that would seem inhospitable to liquid because they are exposed to the extreme vacuum conditions of space.
Pocked with craters, the surfaces of many celestial bodies in our solar system provide clear evidence of a 4.6-billion-year battering by meteoroids and other space debris. But on some worlds, including the giant asteroid Vesta that NASA’s Dawn mission explored, the surfaces also contain deep channels, or gullies, whose origins are not fully understood.
A prime hypothesis holds that they formed from dry debris flows driven by geophysical processes, such as meteoroid impacts, and changes in temperature due to Sun exposure. A recent NASA-funded study, however, provides some evidence that impacts on Vesta may have triggered a less-obvious geologic process: sudden and brief flows of water that carved gullies and deposited fans of sediment. By using lab equipment to mimic conditions on Vesta, the study, which appeared in Planetary Science Journal, detailed for the first time what the liquid could be made of and how long it would flow before freezing.
Although the existence of frozen brine deposits on Vesta is unconfirmed, scientists have previously hypothesized that meteoroid impacts could have exposed and melted ice that lay under the surface of worlds like Vesta. In that scenario, flows resulting from this process could have etched gullies and other surface features that resemble those on Earth.
To explore potential explanations for deep channels, or gullies, seen on Vesta, scientists used JPL’s Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE, to simulate conditions on the giant asteroid that would occur after meteoroids strike the surface.NASA/JPL-Caltech But how could airless worlds — celestial bodies without atmospheres and exposed to the intense vacuum of space — host liquids on the surface long enough for them to flow? Such a process would run contrary to the understanding that liquids quickly destabilize in a vacuum, changing to a gas when the pressure drops.
“Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said project leader and planetary scientist Jennifer Scully of NASA’s Jet Propulsion Laboratory in Southern California, where the experiments were conducted. “But for how long? Most liquids become unstable quickly on these airless bodies, where the vacuum of space is unyielding.”
The critical component turns out to be sodium chloride — table salt. The experiments found that in conditions like those on Vesta, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour. “That’s long enough to form the flow-associated features identified on Vesta, which were estimated to require up to a half-hour,” said lead author Michael J. Poston of the Southwest Research Institute in San Antonio.
Launched in 2007, the Dawn spacecraft traveled to the main asteroid belt between Mars and Jupiter to orbit Vesta for 14 months and Ceres for almost four years. Before ending in 2018, the mission uncovered evidence that Ceres had been home to a subsurface reservoir of brine and may still be transferring brines from its interior to the surface. The recent research offers insights into processes on Ceres but focuses on Vesta, where ice and salts may produce briny liquid when heated by an impact, scientists said.
Re-creating Vesta
To re-create Vesta-like conditions that would occur after a meteoroid impact, the scientists relied on a test chamber at JPL called the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE. By rapidly reducing the air pressure surrounding samples of liquid, they mimicked the environment around fluid that comes to the surface. Exposed to vacuum conditions, pure water froze instantly. But salty fluids hung around longer, continuing to flow before freezing.
The brines they experimented with were a little over an inch (a few centimeters) deep; scientists concluded the flows on Vesta that are yards to tens of yards deep would take even longer to refreeze.
The researchers were also able to re-create the “lids” of frozen material thought to form on brines. Essentially a frozen top layer, the lids stabilize the liquid beneath them, protecting it from being exposed to the vacuum of space — or, in this case the vacuum of the DUSTIE chamber — and helping the liquid flow longer before freezing again.
This phenomenon is similar to how on Earth lava flows farther in lava tubes than when exposed to cool surface temperatures. It also matches up with modeling research conducted around potential mud volcanoes on Mars and volcanoes that may have spewed icy material from volcanoes on Jupiter’s moon Europa.
“Our results contribute to a growing body of work that uses lab experiments to understand how long liquids last on a variety of worlds,” Scully said.
Find more information about NASA’s Dawn mission here:
https://science.nasa.gov/mission/dawn/
News Media Contacts
Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
818-287-4115
gretchen.p.mccartney@jpl.nasa.gov
Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
2024-178
Share
Details
Last Updated Dec 20, 2024 Related Terms
Dawn Asteroids Ceres Jet Propulsion Laboratory Vesta Explore More
5 min read Avalanches, Icy Explosions, and Dunes: NASA Is Tracking New Year on Mars
Article 1 hour ago 5 min read Cutting-Edge Satellite Tracks Lake Water Levels in Ohio River Basin
Article 3 days ago 5 min read NASA Mars Orbiter Spots Retired InSight Lander to Study Dust Movement
Article 4 days ago Keep Exploring Discover More Topics From NASA
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
By NASA
Curiosity Navigation Curiosity Home Mission Overview Where is Curiosity? Mission Updates Science Overview Instruments Highlights Exploration Goals News and Features Multimedia Curiosity Raw Images Images Videos Audio Mosaics More Resources Mars Missions Mars Sample Return Mars Perseverance Rover Mars Curiosity Rover MAVEN Mars Reconnaissance Orbiter Mars Odyssey More Mars Missions The Solar System The Sun Mercury Venus Earth The Moon Mars Jupiter Saturn Uranus Neptune Pluto & Dwarf Planets Asteroids, Comets & Meteors The Kuiper Belt The Oort Cloud 2 min read
Sols 4393-4395: Weekend Work at the Base of Texoli Butte
Caption: NASA’s Mars rover Curiosity acquired this image using its Left Navigation Camera on Dec. 12, 2024, at 23:15:47 UTC — sol 4391, or Martian day 4,391, of the Mars Science Laboratory mission. NASA/JPL-Caltech Earth planning date: Friday, Dec. 13, 2024
Curiosity continues to make great progress over the Mount Sharp bedrock and will spend the weekend investigating the northern base of the “Texoli” butte. The science team back on Earth enjoyed taking in the beautiful views of nearby “Wilkerson” butte and “Gould Mesa” while digging into the workspace in front of us to create a hefty to-do list for our roving geologist on Mars.
The rocks at the rover’s wheels today consisted of dusty, pale-colored bedrock that had a range of textures. We used the dust removal tool (DRT), MAHLI, and APXS instruments to characterize lighter, smooth bedrock at “Calabasas Peak,” and slightly darker, rougher bedrock at “Triunfo Canyon.” The ChemCam team used the Laser-Induced Breakdown Spectroscopy (LIBS) to analyze the composition of the rougher bedrock at “Chilao” and a vein that cuts through the bedrock at “Ojai,” and Mastcam provided the supporting documentation images of each target.
The Mastcam team assembled a variety of images and mosaics in the workspace and beyond. Two stereo mosaics documented the network of fractures in the bedrock at “Fern Dell” while a stereo mosaic of “Amir’s Garden” will be used to observe possible deformation in the rocks. A few single-frame images of troughs in the workspace will be used to investigate active surface processes. Further in the distance, Mastcam created a stereo mosaic of “Jawbone Canyon” to image potential aeolian ripples, and supported a ChemCam long-distance RMI image of a crater in the drive direction called “Grant Lake.” Lastly, ChemCam planned a long-distance RMI image to get a closer look at the structures within Gould Mesa.
Curiosity will drive 44 meters (about 144 feet) to the west over the weekend as we continue to close in on the intriguing boxwork structures. Lastly, the environmental group rounded out the plan with activities including cloud observations, dust-devil monitoring, and surveys of the amount of dust in the atmosphere.
Written by: Sharon Wilson Purdy, Planetary Geologist at the Smithsonian National Air and Space Museum
Share
Details
Last Updated Dec 16, 2024 Related Terms
Blogs Explore More
3 min read Sols 4391-4392: Rounding the Bend
Article
4 days ago
3 min read Sols 4389-4390: A Wealth of Ripples, Nodules and Veins
Article
5 days ago
2 min read Looking Out for ‘Lookout Hill’
Article
6 days ago
Keep Exploring Discover More Topics From NASA
Mars
Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited…
All Mars Resources
Explore this collection of Mars images, videos, resources, PDFs, and toolkits. Discover valuable content designed to inform, educate, and inspire,…
Rover Basics
Each robotic explorer sent to the Red Planet has its own unique capabilities driven by science. Many attributes of a…
Mars Exploration: Science Goals
The key to understanding the past, present or future potential for life on Mars can be found in NASA’s four…
View the full article
-
By NASA
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
When it comes to NASA’s ASTRO CAMP®, the numbers – and impact – of the initiative to help students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics) just continue to grow and grow and grow.
As in recent years, the NASA ASTRO CAMP® Community Partners (ACCP) program surpassed previous milestone marks in fiscal year 2024 by partnering with 373 community sites, including 50 outside the United States, to inspire youth, families, and educators. Participants included students from various population segments, focusing on students from underrepresented groups, accessibility for differently-abled students, and reaching under-resourced urban and rural settings.
“This year has been extremely impactful for the students at ACCP collaborating partner sites,” said Kelly Martin-Rivers, principal investigator for NASA’s ACCP. “A particular highlight was being a part of NASA’s focus on the solar eclipses of 2024, supporting over 42,000 students at 52 NASA ACCP events. Supporting more and more exciting research and activities by the Science Activation grantees and Globe citizen scientists also continues to bring hands-on experiences directly to students across the country and around the world.”
NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® NASA’s ASTRO CAMP® continued its success in fiscal year 2024 as students across the nation and world learn about NASA and STEM (science, technology, engineering, and mathematics. The NASA ASTRO CAMP® Community Partners program partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine.NASA ASTRO CAMP® In the most recent year, the NASA ACCP partnered with 323 sites in 29 states and the District of Columbia. It also reached beyond the borders to partner with 50 sites in six countries, including Mexico, India, Turkey, Canada, Spain, and Ukraine. Overall, almost 150,000 students took part in the program, a 30% increase from fiscal year 2023. In addition, almost 107,000 students took part in special STEM activities, an increase of 43.6% from the previous year’s total of more than 74,000. ACCP trained 1,454 facilitators during Educator Professional Development sessions as well, representing an increase of 25.3% from the prior year.
Taken together, the total NASA ACCP impact exceeded a quarter of a million (257,765) people.
As part of the NASA Science Mission Directorate Science Activation program, ACCP continues to make strides in bridging disparities and breaking barriers in STEM. Demographically, the initiative reached a range of ethnic and multiethnic groups. One-third of participants were African American, with another 13% identified as Hispanic. Participants were almost equally divided between male (52%) and female (48%).
In terms of age, 38% of participants were elementary school students. Another 30% were middle school aged, with the remaining 38% high school students. In a final breakdown, more than 42,000 of the participants were impacted during 52 NASA ACCP solar eclipse events in the spring of 2024.
ACCP activities offer real-world opportunities for students to enhance scientific understanding and contribute to NASA science missions, while also inspiring lifelong learning. The ACCP theme was “NASA Science … Fire to Water to Ice and Beyond!” The program featured materials and activities related to NASA science missions, astrophysics, heliophysics, Earth science, and planetary science.
The unique methodology teaches students to work collaboratively to complete missions and provides trained community educators to implement the themed NASA modules, developed by the ACCP team, seated at NASA’s Stennis Space Center near Bay St. Louis, Mississippi.
ASTRO CAMP began at NASA Stennis as a single one-week camp in the 1990s. Since then, it has developed into several adaptable models for schools, museums, universities, libraries, and youth service organizations, enabling a worldwide expansion.
For more information about becoming a NASA ASTRO CAMP Collaborative Community Partner, contact: Kelly Martin-Rivers at kelly.e.martin-rivers@nasa.gov or 228-688-1500; or Maria Lott at maria.l.lott@nasa.gov or 228-688-1776.
For more on the ASTRO CAMP Collaborative Community Partner Program, visit:
https://www.nasa.gov/stennis/stem-engagement-at-stennis/nasa-accp/.
Share
Details
Last Updated Dec 06, 2024 EditorNASA Stennis CommunicationsContactC. Lacy Thompsoncalvin.l.thompson@nasa.gov / (228) 688-3333LocationStennis Space Center Related Terms
Stennis Space Center Explore More
4 min read Lagniappe for December 2024
Article 2 days ago 5 min read NASA Stennis – An Ideal Place for Commercial Companies
Article 3 weeks ago 4 min read NASA Stennis Propulsion Testing Contributes to Artemis Missions
Article 3 weeks ago View the full article
-
By NASA
Curiosity Navigation Curiosity Home Mission Overview Where is Curiosity? Mission Updates Science Overview Instruments Highlights Exploration Goals News and Features Multimedia Curiosity Raw Images Images Videos Audio Mosaics More Resources Mars Missions Mars Sample Return Mars Perseverance Rover Mars Curiosity Rover MAVEN Mars Reconnaissance Orbiter Mars Odyssey More Mars Missions The Solar System The Sun Mercury Venus Earth The Moon Mars Jupiter Saturn Uranus Neptune Pluto & Dwarf Planets Asteroids, Comets & Meteors The Kuiper Belt The Oort Cloud 3 min read
Sols 4382-4383: Team Work, Dream Work
NASA’s Mars rover Curiosity acquired this image using its Right Navigation Camera on sol 4373 — Martian day 4,373 of the Mars Science Laboratory mission — on Nov. 24, 2024, at 08:32:59 UTC. NASA/JPL-Caltech Earth planning date: Monday, Dec. 2, 2024
Today, after a weeklong holiday break, the team was eager to take a look at Curiosity’s new workspace. After driving 51 meters (about 167 feet) alongside Texoli butte (pictured) we had a whole host of new rocks to examine, and it was one of those curiously perfect planning days where everything falls into place. Our team of geologists here on Earth was busy studying the images our Martian geologist had downlinked to Earth prior to planning, and we scheduled 1.5 hours of science activities on the first sol of this plan. An interesting and varied workspace today saw lots of instruments working together to study the rocks in-depth — teamwork really does make the dream work.
To begin, we are targeting a vertical rock face called “Coronet Lake” near the rover. Coronet Lake has a cluster of nodules on show and we are getting information on the composition of these nodules with APXS and a ChemCam LIBS, as well as a close-up image with our MAHLI instrument. We also have a second MAHLI activity scheduled on a flat rock called “Excelsior Mountain.” Our observant team spotted an interesting-looking rock named “Admiration Point.” This rock may have fallen from the nearby Texoli butte, or could be a meteorite. To test these hypotheses further, we are targeting Admiration Point with a Mastcam mosaic and a ChemCam passive. ChemCam and Mastcam work together again on a target named “Olancha,” an area of rocks that could contain evidence of deformation from when the rocks first formed. Olancha will be targeted with a ChemCam long-distance RMI and a Mastcam mosaic.
Mastcam is finishing off the geological observations here with mosaics of “Angels Camp,” a rock containing veins where water may have once flowed, “Bare Island Lake,” a gray rock containing interesting polygonal ridges, and a trough feature close to Coronet Lake. ChemCam is taking another look back at Gediz Vallis channel to see a transition between light- and dark-toned rocks with a long-distance RMI, and we are rounding off this plan with our standard environmental observations.
As the Geology and Mineralogy theme group Keeper of the Plan for today’s planning, I made sure that this sol was packed full of science activities that the team wanted to schedule. After this busy first sol, Curiosity will be driving about 50 meters (about 164 feet), continuing to make our way out of Gediz Vallis, and we are all very excited to see what the rest of the sulfate-bearing unit has to offer us.
Written by Emma Harris, graduate student at Natural History Museum, London
Share
Details
Last Updated Dec 03, 2024 Related Terms
Blogs Explore More
3 min read 4375-4381: A Stuffed Holiday Plan
Article
19 hours ago
3 min read Sols 4732-4735: I’ll Zap You, My Pretty, and Your Pebble Too
Article
20 hours ago
2 min read You Are Now Arriving at ‘Pico Turquino’
Article
1 day ago
Keep Exploring Discover More Topics From NASA
Mars
Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited…
All Mars Resources
Explore this collection of Mars images, videos, resources, PDFs, and toolkits. Discover valuable content designed to inform, educate, and inspire,…
Rover Basics
Each robotic explorer sent to the Red Planet has its own unique capabilities driven by science. Many attributes of a…
Mars Exploration: Science Goals
The key to understanding the past, present or future potential for life on Mars can be found in NASA’s four…
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.