Showing posts with label NEOWISE. Show all posts
Showing posts with label NEOWISE. Show all posts

Monday, January 19, 2015

NASA's NEOWISE captures Comet C/2014 Q2 (Lovejoy)

Credit: NASA/JPL-Caltech

Comet C/2014 Q2 (Lovejoy) is one of more than 32 comets imaged by NASA's NEOWISE mission from December 2013 to December 2014.

This image of comet Lovejoy combines a series of observations made in November 2013, when comet Lovejoy was 1.7 astronomical units from the sun. (An astronomical unit is the distance between Earth and the sun.)

The image spans half of one degree. It shows the comet moving in a mostly west and slightly south direction. (North is 26 degrees to the right of up in the image, and west is 26 degrees downward from directly right.)

The red colour is caused by the strong signal in the NEOWISE 4.6-micron wavelength detector, owing to a combination of gas and dust in the comet's coma.

Comet Lovejoy is the brightest comet in Earth's sky in early 2015. A chart of its location in the sky during dates in January 2015 is at photojournal.jpl.nasa.gov/catalog/PIA19103 .

Thursday, July 24, 2014

NASA Neowise: A comet that looked like an asteroid

Comet C/2013 UQ4 (Catalina) appeared to be a highly active comet one day past perihelion on July 7, 2014.

Credit: NASA/JPL-Caltech

Comet C/2013 UQ4 (Catalina) has been observed by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft just one day after passing through its closest approach to the sun.

The comet glows brightly in infrared wavelengths, with a dust tail streaking more than 62,000 miles (100,000 kilometers) across the sky.

Its spectacular activity is driven by the vapourisation of ice that has been preserved from the time of planet formation 4.5 billion years ago.

"The tail forms a faint fan as the smaller dust particles are more easily pushed away from the sun by the radiation pressure of the sunlight," said James Bauer, researcher at NASA's Jet Propulsion Laboratory in Pasadena, California.

C/2013 UQ4 takes more than 450 years to orbit the sun once and spends most of its time far away at very low temperatures.

Its orbit is also retrograde, which means that the comet moves around the sun in the opposite direction to the planets and asteroids.

The comet was originally thought to be an asteroid, as it appeared inactive when discovered by the Catalina Sky Survey on October 23, 2013.

NEOWISE also observed the comet to be inactive on New Year's Eve, 2013, but since then the comet has become highly active, allowing astronomers around the world to observe it.

The comet's activity should decline as it once again returns to the cold recesses of space.

Monday, June 9, 2014

NASA NEOWISE: Asteroid 2014 HQ124 to Pass Earth Safely

This diagram shows the orbit of asteroid 2014 HQ124, and its location relative to Earth on June 8.

Image Credit: NASA/JPL-Caltech

A newfound asteroid will safely pass Earth on June 8 from a distance of about 777,000 miles (1.25 million kilometers), more than three times farther away than our moon.

Designated 2014 HQ124, the asteroid was discovered April 23, 2014, by NASA's NEOWISE mission, a space telescope adapted for scouting the skies for asteroids and comets.

The telescope sees infrared light, which allows it to pick up the infrared glow of asteroids and obtain better estimates of their true sizes.

The NEOWISE data estimate asteroid 2014 HQ124 to be between 800 and 1,300 feet (250 and 400 meters).

More than one hundred follow-up observations from NASA-funded, ground-based telescopes and amateur astronomers were used to pin down the orbit of the asteroid out to the year 2200, during which time it poses no risk to Earth.

Its trajectory will continue to be recalculated past that time frame as additional observations are received.

"There is zero chance of an impact," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, California.

"In fact, it's fairly common for asteroids to pass near Earth. You'd expect an object about the size of 2014 HQ124 to pass this close every few years."

Yeomans said that 2014 HQ124 is a good target for radar observations using NASA's Deep Space Network antenna at Goldstone, California, and the Arecibo Observatory in Puerto Rico, shortly after the closest approach on June 8.

Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than otherwise known.

2014 HQ124 is designated a "potentially hazardous asteroid," or PHA, which refers to those asteroids 460 feet (140 meters) in size or larger that pass within 4.6 million miles (7.4 million kilometers) of Earth's orbit around the sun.

There are currently 1,484 known PHAs, but none pose a significant near-term risk of impacting Earth.

"Because NEOWISE is a space telescope observing the dawn and twilight sky at infrared wavelengths, it is particularly good at finding large NEOs that make relatively close passes to Earth," said Amy Mainzer, the principal investigator of NEOWISE at JPL.

"Using infrared light, we can estimate the object’s size, and we can tell that it reflects a fair amount of light. That means it’s most likely a stony object.”

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes.

The Near-Earth Object Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and identifies their orbits to determine if any could be potentially hazardous to our planet.

To date, U.S. assets have discovered more than 98 percent of the known near-Earth objects.

Monday, April 21, 2014

Asteroid Impacts on Earth Obstructed by Red Tape

Artist's view of last year’s fireball explosion over Chelyabinsk, Russia – termed a "superbolide" event.

Credit: Don Davis

Red tape is making it tougher for researchers to study and characterize asteroid strikes on Earth, which are apparently more common than previously thought, experts say.

The bureaucratic snafu affects the use of U.S. government space assets that help scientists study "airbursts" like the meteor that exploded without warning over Russia last year.

At issue is the ability to combine space data with outputs from a global network of seismic, infrasound and hydroacoustic sensors that have been deployed worldwide to provide treaty verification for a nuclear test ban.

This network is the International Monitoring System (IMS) overseen by the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO).

In recent years, the IMS has detected shock waves from many airbursts, providing further evidence that asteroid impacts are more frequent than previously thought.

Ideally, matching observations from spacecraft with measurements from CTBTOs infrasound detectors would give scientists more of a heads-up on what's raining down on Earth, experts say.



Memorandum of agreement
Last year, the Air Force Space Command signed a memorandum of agreement with NASA's Science Mission Directorate.

That document, inked on Jan. 18, 2013, spelled out specifics for the public release of meteor data from sources such as high-flying, secretive U.S. government space sensors.

With that agreement in place, NASA's Near Earth Object (NEO) Observation Program started receiving information on fireball events based on analysis of data collected by U.S. government sensors.

Details of atmospheric meteor explosions, as recorded by U.S. military spacecraft sensors, were posted on a publicly accessible NASA website run by the Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

In fact, the military-civil cooperation was spurred by the details of the February 2013 fireball explosion over Chelyabinsk, Russia, termed a "superbolide" event.

The website postings are designed to assist the scientific community's investigation of bolides, or exceptionally bright fireballs.

However, multiple scientists noted that the JPL website had not been updated recently. That presumably meant that there was some sort of delay, as some fairly big events were detected by infrasound in the last year.

"Because of budget and personnel reductions on our military partner, they ran into workforce issues to accomplish this task," said Lindley Johnson, NEO program executive within the Planetary Science Division of NASA's Science Mission Directorate in Washington, D.C.

"We are already in discussions with them about what it will take to get it restarted," Johnson told reporters

Saturday, March 8, 2014

NASA WISE survey finds thousands of new stars, but no 'Planet X'

A nearby star stands out in red in this image from the Second Generation Digitized Sky Survey (DSS). 

Image credit: DSS /NASA/JPL-Caltech

After searching hundreds of millions of objects across our sky, NASA's Wide-Field Infrared Survey Explorer (WISE) has turned up no evidence of the hypothesized celestial body in our solar system commonly dubbed "Planet X."

Researchers previously had theorized about the existence of this large, but unseen celestial body, suspected to lie somewhere beyond the orbit of Pluto.

In addition to "Planet X," the body had garnered other nicknames, including "Nemesis" and "Tyche."

This recent study, which involved an examination of WISE data covering the entire sky in infrared light, found no object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (au), and no object larger than Jupiter exists out to 26,000 au.

One astronomical unit equals 93 million miles. Earth is 1 au, and Pluto about 40 au, from the Sun.

Kevin Luhman
"The outer solar system probably does not contain a large gas giant planet, or a small, companion star," said Kevin Luhman of the Center for Exoplanets and Habitable Worlds at Penn State University, author of a paper 'A SEARCH FOR A DISTANT COMPANION TO THE SUN WITH WISE' in the Astrophysical Journal describing the results.

But searches of the WISE catalogue are not coming up empty. A second study reveals several thousand new residents in our Sun's "backyard," consisting of stars and cool bodies called brown dwarfs.

Ned Wright
"Neighbouring star systems that have been hiding in plain sight just jump out in the WISE data," said Ned Wright of the University of California, Los Angeles (UCLA), the principal investigator of the mission.

WISE survey finds thousands of new stars, but no 'Planet X'

Data from NASA's WISE, has found no evidence for a hypothesized body sometimes referred to as "Planet X." 

Credit: Penn State University

The second WISE study, which concentrated on objects beyond our solar system, found 3,525 stars and brown dwarfs within 500 light-years of our Sun.

Davy Kirkpatrick
"We're finding objects that were totally overlooked before," said Davy Kirkpatrick of NASA's Infrared and Processing Analysis Center (IPAC) at the California Institute of Technology, Pasadena, Calif.

Kirkpatrick is lead author of the second paper, also in the Astrophysical Journal.

Some of these 3,525 objects also were found in the Luhman study, which catalogued 762 objects.

The WISE mission operated from 2010 through early 2011, during which time it performed two full scans of the sky, with essentially a six-month gap between scans.

The survey captured images of nearly 750 million asteroids, stars and galaxies. In November 2013, NASA released data from the AllWISE program, which now enables astronomers to compare the two full-sky surveys to look for moving objects.

In general, the more an object in the WISE images appears to move over time, the closer it is. This visual clue is the same effect at work when one observes a plane flying low to the ground versus the same plane flying at higher altitude.

Though traveling at the same speed, the plane at higher altitude will appear to be moving more slowly.

Searches of the WISE data catalogue for these moving objects are uncovering some of the closest stars.

The discoveries include a star located about 20 light-years away in the constellation Norma, and as reported last March, a pair of brown dwarfs only 6.5 light-years away, making it the closest star system to be discovered in nearly a century.

Despite the large number of new solar neighbors found by WISE, "Planet X" did not show up.

Previous speculations about this hypothesized body stemmed in part from geological studies that suggested a regular timing associated with mass extinctions on Earth.

The idea was that a large planet or small star hidden in the farthest reaches of our solar system might periodically sweep through bands of outer comets, sending them flying toward our planet.

The Planet X-based mass extinction theories were largely ruled out even prior to the new WISE study.

WISE survey finds thousands of new stars, but no 'Planet X'

The third closest Binary star system to the sun, called WISE J104915.57-531906, is at the center of the larger image, which was taken by NASA's WISE. 

Credit: NASA /JPL /Gemini Observatory /AURA /NSF

Other theories based on irregular comet orbits had also postulated a Planet X-type body.

The new WISE study now argues against these theories as well.

Both of the WISE searches were able to find objects the other missed, suggesting many other celestial bodies likely await discovery in the WISE data.

"We think there are even more stars out there left to find with WISE. We don't know our own sun's backyard as well as you might think," said Ned Wright.

WISE was put into hibernation upon completing its primary mission in 2011.

In September 2013, it was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects.

NEOWISE will also characterise previously known asteroids and comets to better understand their sizes and compositions.

Monday, March 3, 2014

NASA NEOWISE Image: First Comet observed

Comet NEOWISE was first observed by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft on Valentine's Day, 2014.

NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft has spotted a never-before-seen comet—its first such discovery since coming out of hibernation late last year.

"We are so pleased to have discovered this frozen visitor from the outermost reaches of our solar system," said Amy Mainzer, the mission's principal investigator from NASA's Jet Propulsion Laboratory in Pasadena, Calif.

"This comet is a weirdo - it is in a retrograde orbit, meaning that it orbits the sun in the opposite sense from Earth and the other planets."

Officially named "C/2014 C3 (NEOWISE)", the first comet discovery of the renewed mission came on Feb. 14 when the comet was about 143 million miles (230 million kilometers) from Earth.

Although the comet's orbit is still a bit uncertain, it appears to have arrived from its most distant point in the region of the outer planets.

The mission's sophisticated software picked out the moving object against a background of stationary stars.

As NEOWISE circled Earth, scanning the sky, it observed the comet six times over half a day before the object moved out of its view.

The discovery was confirmed by the Minor Planet Center, Cambridge, Mass., when follow-up observations were received three days later from the Near Earth Object Observation project Spacewatch, Tucson, Ariz.

Other follow-up observations were then quickly received. While this is the first comet NEOWISE has discovered since coming out of hibernation, the spacecraft is credited with the discovery of 21 other comets during its primary mission.

Originally called the Wide-field Infrared Survey Explorer (WISE), the spacecraft was shut down in 2011 after its primary mission was completed.

In September 2013, it was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects.

NEOWISE will also characterize previously known asteroids and comets to better understand their sizes and compositions.

Friday, January 24, 2014

NEOWISE celebrates first month of operations after reactivation

In its first 25 days of operations, the newly reactivated NEOWISE mission has detected 857 minor bodies in our solar system, including 22 near-Earth objects (NEOs) and four comets. 

Three of the NEOs are new discoveries; all three are hundreds of meters in diameter and dark as coal.

The mission has just passed its post-restart survey readiness review, and the project has verified that the ability to measure asteroid positions and brightness is as good as it was before the spacecraft entered hibernation in early 2011.

At the present rate, NEOWISE is observing and characterizing approximately one NEO per day, giving astronomers a much better idea of the objects' sizes and compositions.

Out of the more than 10,500 NEOs that have been discovered to date, only about 10 percent have had any physical measurements made of them; the reactivated NEOWISE will more than double that number.

Friday, December 13, 2013

NASA WISE Image: Helix Nebula

A dying star, called the Helix nebula, is shown surrounded by the tracks of asteroids in an image captured by NASA's Wide-field Infrared Survey Explorer (WISE)

Image Credit: NASA/JPL-Caltech/UCLA

In an unexpected juxtaposition of cosmic objects that are actually quite far from each other, a newly released image from NASA's Wide-Field Infrared Survey Explorer (WISE) shows a dying star, called the Helix nebula, surrounded by the tracks of asteroids.

The nebula is far outside our solar system, while the asteroid tracks are inside our solar system.

The portrait, discovered by chance in a search for asteroids, comes at a time when the mission's team is celebrating its fourth launch anniversary -- and new lease on life.

In August, NASA decided to bring WISE out of hibernation to search for more asteroids. The mission was rechristened NEOWISE, formerly the name of the asteroid-hunting portion of WISE.

"I was recently looking for asteroids in images collected in 2010, and this picture jumped out at me," said Amy Mainzer, the NEOWISE principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "I recognized the Helix nebula right away."

WISE launched into the morning skies above Vandenberg Air Force Base in central California on Dec. 14, 2009.

By early 2011, it had finished scanning the entire sky twice in infrared light, snapping pictures of nearly one billion objects, including remote galaxies, stars and asteroids.

Upon completing its main goals, WISE was put to sleep. Now, engineers are bringing the spacecraft out of slumber, as it cools back down to the chilly temperatures required for infrared observations.

The spacecraft no longer has onboard coolant, but two of its infrared channels still work and can be used for asteroid hunting.

"WISE is the spacecraft that keeps on giving," said Ned Wright of UCLA, the principal investigator of WISE before it transitioned into NEOWISE.

In the Helix nebula image, infrared wavelengths of light have been assigned different colors, with longer wavelengths being red, and shorter, blue.

The bluish-green and red materials are expelled remnants of what was once a star similar to our sun. As the star aged, it puffed up and its outer layers sloughed off.

The burnt-out core of the star, called a white dwarf, is heating the expelled material, inducing it to glow with infrared light.

Over time, the brilliant object, known as a planetary nebula, will fade away, leaving just the white dwarf.

Wednesday, December 4, 2013

NASA WISE: Massive black hole duo

Two black holes are entwined in a gravitational tango in this artist's conception. 

Supermassive black holes at the hearts of galaxies are thought to form through the merging of smaller, yet still massive black holes, such as the ones depicted here. 

NASA's Wide-field Infrared Survey Explorer (WISE), helped lead astronomers to what appears to be a new example of a dancing black hole duo. 

Called WISE J233237.05-505643.5, the suspected black hole merger is located about 3.8 billion light-years from Earth, much farther than other black hole binary candidates of a similar nature. 

Credit: NASA

Astronomers have spotted what appear to be two supermassive black holes at the heart of a remote galaxy, circling each other like dance partners.

The incredibly rare sighting was made with the help of NASA's Wide-field Infrared Survey Explorer (WISE).

Follow-up observations with the Australian Telescope Compact Array near Narrabri, Australia, and the Gemini South telescope in Chile, revealed unusual features in the galaxy, including a lumpy jet thought to be the result of one black hole causing the jet of the other to sway.

"We think the jet of one black hole is being wiggled by the other, like a dance with ribbons," said Chao-Wei Tsai of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is lead author of a paper on the findings appearing in the Dec. 10 issue of Astrophysical Journal.

"If so, it is likely the two black holes are fairly close and gravitationally entwined."

The findings could teach astronomers more about how supermassive black holes grow by merging with each other.

The WISE satellite scanned the entire sky twice in infrared wavelengths before being put into hibernation in 2011. NASA recently gave the spacecraft a second lease on life, waking it up to search for asteroids, in a project called NEOWISE.

The new study took advantage of previously released all-sky WISE data. Astronomers sifted through images of millions of actively feeding supermassive black holes spread throughout our sky before an oddball, also known as WISE J233237.05-505643.5, jumped out.

"At first we thought this galaxy's unusual properties seen by WISE might mean it was forming new stars at a furious rate," said Peter Eisenhardt, WISE project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and a co-author of the study.

"But on closer inspection, it looks more like the death spiral of merging giant black holes."

Almost every large galaxy is thought to harbor a supermassive black hole filled with the equivalent in mass of up to billions of suns.

How did the black holes grow so large? One way is by swallowing ambient materials. Another way is through galactic cannibalism.

When galaxies collide, their massive black holes sink to the center of the new structure, becoming locked in a gravitational tango. Eventually, they merge into one even-more-massive black hole.

More information: Preprint paper: arxiv.org/abs/1310.2257

Thursday, August 22, 2013

NEOWISE: NASA WISE spacecraft reactivated to hunt for asteroids

This artist's concept shows the Wide-field Infrared Survey Explorer, (WISE) spacecraft, in its orbit around Earth. 

In September of 2013, engineers will attempt to bring the mission out of hibernation to hunt for more asteroids and comets in a project called NEOWISE

Image credit: NASA/JPL-Caltech

A NASA spacecraft that discovered and characterized tens of thousands of asteroids throughout the solar system before being placed in hibernation will return to service for three more years starting in September, assisting the agency in its effort to identify the population of potentially hazardous near-Earth objects, as well as those suitable for asteroid exploration missions.

The Wide-field Infrared Survey Explorer (WISE) will be revived next month with the goal of discovering and characterizing near-Earth objects (NEOs), space rocks that can be found orbiting within 45 million kilometers (28 million miles) from Earth's path around the sun.

NASA anticipates WISE will use its 16-inch (40-centimeter) telescope and infrared cameras to discover about 150 previously unknown NEOs and characterize the size, albedo and thermal properties of about 2,000 others—including some of which could be candidates for the agency's recently announced asteroid initiative.

John Grunsfeld
"The WISE mission achieved its mission's goals and as NEOWISE extended the science even further in its survey of asteroids. NASA is now extending that record of success, which will enhance our ability to find potentially hazardous asteroids, and support the new asteroid initiative," said John Grunsfeld, NASA's associate administrator for science in Washington.

"Reactivating WISE is an excellent example of how we are leveraging existing capabilities across the agency to achieve our goal."

NASA's asteroid initiative will be the first mission to identify, capture and relocate an asteroid.

It represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet.

The asteroid initiative brings together the best of NASA's science, technology and human exploration efforts to achieve President Obama's goal of sending humans to an asteroid by 2025.

Launched December 2009 to look for the glow of celestial heat sources from asteroids, stars and galaxies, WISE made about 7,500 images every day during its primary mission from January 2010 to February 2011.

As part of a project called NEOWISE, the spacecraft made the most accurate survey to date of NEOs. NASA turned most of WISE's electronics off when it completed its primary mission.

"The data collected by NEOWISE two years ago have proven to be a gold mine for the discovery and characterization of the NEO population," said Lindley Johnson, NASA's NEOWISE program executive in Washington.

"It is important that we accumulate as much of this type of data as possible while the WISE spacecraft remains a viable asset."

Because asteroids reflect but do not emit visible light, infrared sensors are a powerful tool for discovering, cataloging and understanding the asteroid population.

Depending on an object's reflectivity, or albedo, a small, light-colored space rock can look the same as a big, dark one. As a result, data collected with optical telescopes using visible light can be deceiving.

Thursday, May 30, 2013

NASA WISE mission finds lost asteroid family members

This artist's conception shows how families of asteroids are created. 

Over the history of our solar system, catastrophic collisions between asteroids located in the belt between Mars and Jupiter have formed families of objects on similar orbits around the sun. 

Image credit: NASA/JPL-Caltech

Data from NASA's Wide-field Infrared Survey Explorer (WISE) have led to a new and improved family tree for asteroids in the main belt between Mars and Jupiter.

Astronomers used millions of infrared snapshots from the asteroid-hunting portion of the WISE all-sky survey, called NEOWISE, to identify 28 new asteroid families.

The snapshots also helped place thousands of previously hidden and uncategorized asteroids into families for the first time.

The findings are a critical step in understanding the origins of asteroid families, and the collisions thought to have created these rocky clans.

"NEOWISE has given us the data for a much more detailed look at the evolution of asteroids throughout the solar system," said Lindley Johnson, the program executive for the Near-Earth Object Observation Program at NASA Headquarters in Washington.

"This will help us trace the NEOs back to their sources and understand how some of them have migrated to orbits hazardous to the Earth."

The main asteroid belt is a major source of near-Earth objects (NEOs), which are those asteroids and comets that come within 28 million miles (45 million kilometers) of Earth's path around the sun.

Some near-Earth objects start out in stable orbits in the main asteroid belt, until a collision or gravitational disturbance flings them inward like flippers in a game of pinball.

The NEOWISE team looked at about 120,000 main belt asteroids out of the approximately 600,000 known.

They found that about 38,000 of these objects, roughly one third of the observed population, could be assigned to 76 families, 28 of which are new.

In addition, some asteroids thought to belong to a particular family were reclassified.

An asteroid family is formed when a collision breaks apart a large parent body into fragments of various sizes.

Some collisions leave giant craters. For example, the asteroid Vesta's southern hemisphere was excavated by two large impacts.

Other smash-ups are catastrophic, shattering an object into numerous fragments, as was the case with the Eos asteroid family.

The cast-off pieces move together in packs, traveling on the same path around the sun, but over time the pieces become more and more spread out.

More information: Paper: dx.doi.org/10.1088/0004-637X/770/1/7