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In this image from April 12, 1981, the first space shuttle, STS-1, launches from NASA’s Kennedy Space Center in Florida with NASA astronauts John W. Young, commander, and Robert L. Crippen, pilot, aboard.

STS-1 was meant to demonstrate a safe launch into orbit and a safe return of the orbiter and crew, as well as verify the combined performance of the entire shuttle vehicle – orbiter, solid rocket boosters and external tank.

The first space shuttle landed at Edwards Air Force Base in California on April 14, 1981, after having successfully tested its major systems.

Image Credit: NASA

The hatching of the 250th California condor chick at the San Diego Zoo marks a notable milestone for a species that narrowly evaded extinction

The hatching of the 250th California condor chick at the San Diego Zoo marks a notable milestone for a species that narrowly evaded extinction

NASA will host a media teleconference at 1 p.m. EDT, Monday, April 15, to discuss the agency’s response to a Mars Sample Return Independent Review Board report from September 2023, including next steps for the program.

The teleconference will livestream at:

https://www.nasa.gov/nasatv

Mars Sample Return has been a major long-term goal of international planetary exploration for the past two decades. NASA’s Perseverance rover is collecting compelling science samples that will help scientists understand the geological history of Mars, the evolution of its climate, and prepare for future human explorers. The return of the samples will also help NASA’s search for signs of ancient life.

The media teleconference will share the agency’s recommendations regarding a path forward for Mars Sample Return within a balanced overall science program. The speakers include:

• NASA Administrator Bill Nelson
• Nicky Fox, associate administrator, Science Mission Directorate

Media who wish to participate in the teleconference should RSVP by 11 a.m. on April 15 by emailing dewayne.a.washington@nasa.gov.

For more information on NASA’s Mars exploration, visit:

http://nasa.gov/mars

-end-

Dewayne Washington / Karen Fox
Headquarters, Washington
202-358-1100
dewayne.a.washington@nasa.gov / karen.fox@nasa.gov  

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Details Last Updated Apr 12, 2024 LocationNASA Headquarters Related Terms

• Missions
• Mars Sample Return (MSR)

Most satellites share the same fate at the end of their lives. Their orbits decay, and eventually, they plunge through the atmosphere toward Earth. Most satellites are destroyed during their rapid descent, but not always

Heavy pieces of the satellite, like reaction wheels, can survive and strike the Earth. Engineers are trying to change that.

Satellite debris can strike Earth and is a potential hazard, though the chances of debris striking anything other than ocean or barren land are low. Expired satellites usually just re-enter the atmosphere and burn up. But there are a lot of satellites, and their number keeps growing.

In February 2024, the ESA’s European Remote Sensing 2 (ERS2) satellite fell to Earth. The ESA tracked the satellite and concluded that it posed no problem. “The odds of a piece of satellite falling on someone’s head is estimated at one in a billion,” ESA space debris system engineer Benjamin Bastida Virgili said.

That would be fine if ERS 2 was an isolated incident. But, according to the ESA, an object about as massive as ERS 2 reenters Earth’s atmosphere every one to two weeks. The statistics may show there’s no threat to people, but statistics are great until you’re one of them.

The ESA’s ERS-2 Earth observation satellite was destroyed when it re-entered Earth’s atmosphere on February 21st, 2004. Heavy parts of satellites, like reaction wheels, don’t always burn up in the atmosphere and can pose a hazard. ESA engineers are working on reaction wheels that will break into pieces to reduce the hazard. Image Credit: Fraunhofer FHR

The risk of being struck by chunks of a satellite isn’t zero. In 1997, a piece of mesh from a Delta II rocket struck someone’s shoulder in Oklahoma. It was a light piece of debris, so the person was okay. But it was an instructive event.

The heaviest parts of satellites, like reaction wheels, can be hazardous because they may not be destroyed during re-entry. Reaction wheels provide three-axis control for satellites without the need for rockets. They give satellites fine pointing accuracy and are useful for rotating satellites in very small amounts.

Reaction wheels can be quite massive. The Hubble Space Telescope has four reaction wheels weighing 45 kg (100 lbs) each. Other satellites don’t have such massive wheels, but the Hubble’s hefty wheels indicate the extent of the hazard. ESA engineers are designing reaction wheels that will break up during re-entry to reduce the hazard of one striking Earth.

“… the need is becoming urgent as more and more satellites are placed in space.”

Kobyé Bodjona, Mechanisms Engineer at the ESA

As part of the design process, they’re testing their wheels in a plasma wind tunnel at the University of Stuttgart Institute of Space Systems. The heated plasma in the tunnel moves at several km/sec, mimicking the friction a satellite is exposed to when it plunges through Earth’s atmosphere. The wheel is rotated inside the tunnel as if tumbling through the atmosphere.

At a recent Space Mechanisms Workshop at ESA’s ESTEC technical center in the Netherlands, engineers showed a clip of the blow-torch effect that the atmosphere has on falling debris.

“Space mechanisms cover everything that enables movement aboard a satellite, from deployment devices to reaction wheels,” explains workshop co-organizer Geert Smet.

“But these mechanisms often use materials such as steel or titanium that are more likely to survive reentry into the atmosphere. This is a problem because our current regulations say reentering satellites should present less than one in 10,000 risks of harming people or property on the ground or even one in 100 000 for large satellite constellations. ESA’s Clean Space group is reacting by D4D—devising methods to make total disintegration of a mission more likely, including mechanisms.”

The effort to make satellites disintegrate completely goes back a few years. The ESA program Design for Demise (D4D) is helping satellite manufacturers comply with the Space Debris Mitigation (SDM) requirements. It’s aimed at eliminating debris falling to Earth, removing debris already in orbit, and designing satellites that don’t linger in orbit after their missions have ended.

At the recent workshop, the ESA revealed more of its plans for active debris removal. There’s a push to develop dedicated spacecraft that can attach themselves to derelict satellites and force them into reentry. This will help remove dead satellites from the congested Low Earth Orbit.

“The idea behind this event is to present the mechanisms community with the latest research on space debris to see how they might contribute to the work going on,” said Kobyé Bodjona, Mechanisms Engineer at the ESA. “It’s important because large system integrators—the big companies that lead satellite projects—are going to need systems that are fully compliant with debris mitigation regulations. And the need is becoming urgent as more and more satellites are placed in space.”

The post Watch a Satellite Reaction Wheel Melt in a Simulated Orbital Re-Entry appeared first on Universe Today.

The closest extreme magnetic dead star or magnetar to Earth suddenly burst back to life to give astronomers a sight of unexpected and unexplained phenomena that are unlike anything seen before.

Bonobos have long been regarded as the peaceful ape, in sharp contrast with violent chimpanzees, but a study based on thousands of hours of observations suggests the real story is more nuanced

Bonobos have long been regarded as the peaceful ape, in sharp contrast with violent chimpanzees, but a study based on thousands of hours of observations suggests the real story is more nuanced

The arms of a grand design spiral galaxy 60,000 light-years across are

Compound events in which coastal flooding and heat waves occur at the same time are happening more often as the planet warms

CNN is set to conclude airing a four-part series on space shuttle Columbia's ill-fated last return to Earth. "Space Shuttle Columbia: The Final Flight" airs on Sunday (April 14).

A SpaceX Falcon 9 rocket stage lifted off for a record-setting 20th time on Friday (April 12), sending 23 Starlink internet satellites to orbit.

New discoveries demystify the bizarre force that binds atomic nuclei together

Ancient prophecies of worlds destroyed by fire are becoming realities. How will we respond?

An Arctic-wide survey has found that the permafrost region is emitting more carbon into the atmosphere than it absorbs, causing the planet to heat even further

An Arctic-wide survey has found that the permafrost region is emitting more carbon into the atmosphere than it absorbs, causing the planet to heat even further

Several media outlets have incorrectly claimed that explosive solar flares were spotted during the April 8 total solar eclipse. But there were no flares during totality, so what did people see?

In just one year of observations, a program that is creating the largest 3D map of the universe to date has sniffed out hints that dark energy may be stranger than scientists supposed

3 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater) Though the art of origami is centuries old, until the late 20th century it was considered virtually impossible to make insects or other figures with many long, complex protrusions. That changed with the introduction of math-based origami design, which Lang helped pioneer. Today, he’s still drawn to the challenges presented by insects and other arthropods, and they are well-represented in the menagerie of his origami gallery.

After uncovering the mathematical underpinnings of origami, Robert Lang left a 20-year engineering career, including over four years at NASA’s Jet Propulsion Laboratory in Southern California, to pursue his lifelong passion. However, while he was working at JPL, Lang picked up an important key to computational design, allowing him to turn paper into impossibly intricate 3D forms.

In the center’s Micro Devices Laboratory in the late 1980s and early ’90s, Lang worked on building an optical computer that uses light rather than electricity to carry out calculations. This work introduced him to the concept of nonlinear constrained optimization.

Lang explained that a simple nonlinear constrained optimization problem is like packing different-sized balls into a box. The constraint is that the balls can’t overlap, and the solutions are nonlinear because the balls can be any direction or distance from each other. The optimization is making the box as small as possible.

System design optimization for lasers and other components requires minimizing energy consumption, semiconductor materials, and other costs. In origami, optimization means creating the most extensive form possible using a single sheet of paper.

In the mid-1990s, he took his expertise gain at JPL and created an open-source software called TreeMaker, the first program available to design complex origami figures. Lang’s design software uses an equation to map the points that will become features like a head and limbs. It helps decide exactly how far apart any two points have to be, depending on their location in the final shape.

In 2001, he left his last engineering job to become a full-time origamist, and he remains one of the world’s leading figures at the intersection of math and paper folding. Lang’s work ranges from small paper sculptures to huge public art made from metal and other materials, which he co-creates with other artists.

Since Lang left NASA, the agency has called him back in to consult on a few projects that capitalized on his dual background in engineering and origami. One of those was the Starshade concept, a design for a baseball diamond-sized disk that would fold up tightly to fit in a rocket fairing and then unfurl in space. There, it would block the light from a given star so a space telescope could photograph its planets. Credit: NASA

The art of folding has even crept into space technology in recent years. Commercial companies now seek out Lang for his origami and engineering backgrounds to consult on folding hardware, including a collapsible radio antenna and Lawrence Livermore National Laboratory’s Eyeglass space telescope. He’s also returned to NASA to help figure out how to fold large objects for launch inside rocket fairings.

“The irony is that, when I was employed full-time at NASA, I was not working on origami, but after I left, I’ve been invited back a couple of times to work on origami-related projects,” he said.

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Details Last Updated Apr 12, 2024 Related Terms

• General
• Jet Propulsion Laboratory
• Spinoffs
• Technology Transfer
• Technology Transfer & Spinoffs

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