Universe Today

January 14, 2008April 26, 2016 by Nancy Atkinson

MESSENGER and other Significant Mission Events in 2008

Today, the MESSENGER spacecraft will perform a significant task in its mission by making its first flyby of Mercury (see more info below). Additionally, other spacecraft that are out doing their jobs in various locations of our solar system will have significant mission events occur in 2008. Let’s take a look at the big events coming up this year.

January 14: MESSENGER Flyby of Mercury

Messenger, the MEercury Surface Space ENvironment GEochemistry and Ranging spacecraft, will be the first spacecraft to visit Mercury in almost 33 years. It will explore and take close-up images of parts of the planet that we’ve never seen before. This is the first of three flybys of Mercury the spacecraft will take before settling into orbit in 2011. MESSENGER’s cameras and other instruments will collect more than 1,200 images and make other observations during this approach, encounter and departure. The closest approach of the flyby will occur at 19:04:42 UTC (2:04:42 EST), but mission managers said pictures from the event may not be released for up to a week.

March 12: Cassini flies through the plume of Enceladusâ€™ geyser

The Cassini spacecraft will fly extremely close to Saturn’s moon Enceladus at an altitude of only 23 km (14 mi), and actually fly through the plume of an active geyser on the moon’s south pole. How such a cold moon could host an area warm enough to have erupting water vapor is a mystery. Scientists are pondering if Enceladus has active ice volcanism, and if so, is it due to ice sublimating, like a comet, or due to a different mechanism, like boiling water as in Old Faithful at Yellowstone. This flyby will help answer those questions.

Cassini will also have several relatively close flybys this year of the moon Titan. The flybys will occur on Feb. 22, March 25, and May 12.

May 25: Phoenix lands on Mars

Phoenix will land in the north polar region of Mars and will help characterize the climate and geology of the Red Planet, as well as possibly determine if live ever arose on Mars. Pursuing NASA’s “Follow the Water” strategy, the lander will dig through soil to reach water ice with its robotic arm and perform numerous scientific experiments. Phoenix launched on Aug. 4, 2007. University of Arizona’s Phoenix page

September 5: Rosetta flyby of Asteroid Steins

The Rosetta spacecraft is on its way to orbit comet 67P Churyumov-Gerasimenko in 2014, but in the meantime it will pass by Asteroid 2867 Steins. During the flyby, Rosetta will study Steins to determine and characterize the asteroid’s surface composition and morphology. Asteroid Steins is roughly 10 km in diameter.

January 14, 2008December 26, 2015 by Nancy Atkinson

2008 Launch Calendar and Preview

2008 will be a busy year throughout the world and our solar system as various robotic and human missions are slated to begin their journeys of exploration and science. One of the most exciting and nail biting times of a mission is the launch, and following is a list of mission launches that will occur in 2008. Included is information about each mission and links to mission homepages, as well as launch locations, just in case youâ€™ll be in the area. Of course, as the year rolls along, weâ€™ll be covering each of the missions in Universe Today.

2008 Launches:

All launch dates are subject to change. The launches listed are non-military scientific robotic and human missions.

January 30: THEOS (Thailand Earth Observing System) (GISTDA)
Launch site: Yasny, in Orenburg Oblast, Russia Dombarovsky Cosmodrome, Russia
Launch vehicle: Kosmotras Dniepr rocket
THOES will be used for cartography, agricultural monitoring, forestry management, coastal zone monitoring and flood risk management in Thailand. The spacecraft was built by EADS Astrium in France.

Feb. 5: Progress 28P (Roskosmos)
Launch site: Baikonur Cosmodrome, Kazakhstan
Launch Vehicle: Soyuz
The 28th Progress cargo delivery ship to the International Space Station (ISS).

Feb. 7: Space Shuttle Mission: STS-122 (NASA)
Launch Site: Kennedy Space Center – Launch Pad 39A
Launch Vehicle: Space Shuttle Atlantis
STS-122 will deliver the Columbus European Laboratory Module to the ISS, and is the twenty-fourth mission to the space station.

February 22: ESAâ€™s ATV Jules Verne (ESA)
Launch site: ELA-3, Kourou, French Guiana
Launch vehicle: Ariane 5
The European Space Agencyâ€™s first Automated Transfer Vehicle â€œJules Verneâ€? will dock with the ISS to bring supplies and equipment to the station.

Mid to Late March: Space Shuttle Mission: STS-123 (NASA)
Launch Vehicle: Space Shuttle Endeavour
Launch Site: Kennedy Space Center – Launch Pad 39A
Mission STS-123 will deliver the pressurized section of the Kibo Japanese Experiment Logistics Module (ELM-PS) on the twenty-fifth mission to the ISS.

April 8: Soyuz ISS 16S (Roskosmos)
Launch site: Baikonur Cosmodrome, Kazakhstan
Launch vehicle: Soyuz
Flight of the manned Soyuz TMA-12 spacecraft to the International Space Station with members of the Expedition 17 crew. The capsule will remain at the station for about six months, providing an escape vehicle for the crew.

April 9: Chandrayaan-1 (ISRO)
Launch site: Satish Dhawan Space Centre, India
Launch vehicle: Indiaâ€™s PSLV (Polar Satellite Launch Vehicle)
Indiaâ€™s lunar orbiter mission will create a 3-D atlas of the moon, as well as conduct chemical and mineral mapping of the entire lunar surface. NASA’s Chandrayaan webpage

April 24: Space Shuttle Mission STS-124 (NASA)
Launch Site: Kennedy Space Center – Launch Pad 39A
Launch Vehicle: Space Shuttle Discovery
Space Shuttle Discovery on mission STS-124 will transport the Kibo Japanese Experiment Module – Pressurized Module (JEM-PM) and the Japanese Remote Manipulator System (JEM-RMS) to the International Space Station.

May 14: Progress 29P (Roskosmos)
Launch site: Baikonur Cosmodrome, Kazakhstan
Launch Vehicle: Soyuz
The 29th Progress cargo delivery ship to the International Space Station (ISS).

May 15: GOCE satellite (Gravity field and steady state Ocean Circulation Explorer)(ESA)
Launch site: Plesetsk, Russia
Launch vehicle: Rokot / Briz KM
GOCE will measure the Earth’s gravity field and model the geoid, or hypothetical surface of the Earth, with extremely high accuracy and spatial resolution. It also will provide insight into the physics and dynamics of the Earth’s interior, such as volcanism and earthquakes.

May 16: GLAST (Gamma-ray Large Area Space Telescope) (NASA)
Launch Site: Cape Canaveral Air Force Station – Launch Complex 17 – Pad 17-B
Launch Vehicle: United Launch Alliance Delta II
GLAST the will have the ability to detect gamma rays in a range of energies from thousands to hundreds of billions of times more energetic than the light visible to the human eye. Radiation of such magnitude can only be generated under the most extreme conditions, thus GLAST will focus on studying the most energetic objects and phenomena in the universe, such as black holes, gamma ray bursts, neutron stars and cosmic rays. GLAST follows in the footsteps of the Compton Gamma Ray Observatory.

June 15: OSTM/Jason 2 (Ocean Surface Topography Mission)
Launch Site: Vandenberg Air Force Base – Launch Pad SLC-2
Launch Vehicle: United Launch Alliance Delta II
This will be a follow-on to the Jason mission to measure sea surface height and determine the variability of ocean circulation at decadal time scales with combined data from the Topex/Poseidon mission and Jason . This is a joint U.S., Canadian and European project.

July 15: IBEX (Interstellar Boundary Explorer)
Launch Site: Reagan Test Site, Kwajalein Atoll
Launch Vehicle: Orbital Sciences Pegasus XL Rocket
IBEX’s science objective is to discover the global interaction between the solar wind and the interstellar medium. It will take a set of global energetic neutral atom images to determine the strength and structure of the termination shock, and study the properties of the solar wind flow beyond the termination shock and in the heliotail.

July 20: GOES-O Geostationary Operational Environmental Satellite
Launch Site: Cape Canaveral Air Force Station – Launch Complex 17
Launch Vehicle: United Launch Alliance Delta IV
NASA and the National Oceanic and Atmospheric Administration (NOAA) are actively engaged in a cooperative program, the multimission series N-P. This series will be a vital contributor to weather, solar and space operations, and science. The weather satellite will orbit 22,300 miles above the planet to monitor conditions across the U.S.

July 31: Herschel–Planck (ESA)
Launch site: CSG, Kourou, French Guiana
Launch vehicle: Ariane 5
One rocket will launch two different spacecraft, the Herschel infrared space observatory and the Planck mission to study the cosmic microwave background radiation. Herschel is a 3.5 meter diameter reflecting telescope with instruments cooled to close to absolute zero to observe at wavelengths that not been previously explored. After a four-month journey from Earth, Herschel will spend at least three years in orbit around the second Lagrange point of the Sun-Earth system. Planck will image the anisotropies of the Cosmic Background Radiation Field over the whole sky.

Aug. 7: Space Shuttle Mission: STS-125 (NASA)
Launch Site: Kennedy Space Center – Launch Pad 39A
Launch Vehicle: Space Shuttle Atlantis
Space Shuttle Atlantis will fly seven astronauts into space for the fifth and final servicing mission to the Hubble Space Telescope. During the 11-day flight, the crew will repair and improve the observatory’s capabilities through 2013.

Aug. 12: Progress 30P (Roskosmos)
Launch site: Baikonur Cosmodrome, Kazakhstan
Launch vehicle: Soyuz rocket
The 30th Progress cargo delivery ship to the International Space Station.

Sept. 18: Space Shuttle Mission STS-126 (NASA)
Launch Site: Kennedy Space Center – Launch Pad 39A
Launch Vehicle: Space Shuttle Endeavour
ISS assembly flight ULF2 will deliver a Multi-Purpose Logistics Module to the International Space Station.

Oct. 12: Soyuz ISS 17S (Roskosmos)
Launch site: Baikonur Cosmodrome, Kazakhstan
Launch vehicle: Soyuz
The manned Soyuz TMA-13 spacecraft flies to the International Space Station with members of the Expedition 18 crew. The capsule will remain at the station for about six months, providing an escape vehicle for the crew

October TBD: SMOS (Soil Moisture and Ocean Salinity) & Proba-2 microsatellite (ESA)
Launch site: Plesetsk, Russia
Launch vehicle: Rokot
SMOS will measure microwave radiation emitted from the Earth’s surface at L-band (1.4 GHz) using an interferometric radiometer. Proba-2 is a technology demonstration satellite.

Oct. 28: LRO (Lunar Reconnaissance Orbiter) & LCROSS (Lunar Crater Observation and Sensing Satellite) (NASA)
Launch Site: Cape Canaveral Air Force Station – Launch Complex 41
Launch Vehicle: United Launch Alliance Atlas V
LRO will spend at least a year mapping the surface of the moon to help select safe landing sites for astronauts, identify lunar resources and study how the moon’s environment will affect humans. LCROSS will study the poles of the moon to confirm the presence or absence of water ice in a permanently shadowed craters.

Dec 1: SDO (Solar Dynamics Observatory) (NASA)
Launch Site: Cape Canaveral Air Force Station – Launch Complex 41
Launch Vehicle: United Launch Alliance Atlas V
SDO will help to understand the Sun’s influence on Earth and Near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously. This is the first Space Weather Research Network mission in the Living With a Star Program of NASA.

Dec 15: OCO (Orbiting Carbon Observatory) (NASA)
Launch Site: Vandenberg Air Force Base, California – Launch Pad SLC 576-E
Launch Vehicle: Orbital Sciences Taurus Rocket
OCO will collect precise global measurements of carbon dioxide (CO2) in the Earth’s atmosphere to improve our understanding of the natural processes and human activities that may have an influence on this greenhouse gas. OCO is a new Earth orbiting mission sponsored by NASA’s Earth System Science Pathfinder Program.

January 12, 2008December 26, 2015 by Ian O'Neill

Radioactive Hot Spots on Earth’s Beaches May Have Sparked Life

We’ve heard about life being created in a puddle of primordial chemical soup, sparked by lightning strikes, or organic molecules falling to Earth from comets or planets, such as Mars. But now, there is an alternative. Early Earth was radioactive; the Moon also had a lower orbit, generating strong tidal forces. Due to the close proximity to abundant water, radioactive beaches may have possessed all the essential ingredients for organic compounds, and eventually life, to thrive.

Research by the University of Washington, Seattle, suggests that perhaps the highly radioactive environment of Earth some 4 billion years ago may have been the ideal time for life to form. The orbit of the Moon also had a part to play in this offbeat theory.

Through strong tidal forces by a Moon that orbited far closer to the Earth than it does today, radioactive elements accumulated on the beaches could be gravitationally sorted. The chemical energy in these beach hot spots was probably high enough to allow self-sustaining fission processes (which occurs in natural concentrations of uranium). The main product from fission is heat, therefore powering chemical processes and the generation of organic, life-giving compounds.

“Amino acids, sugars and [soluble] phosphate can all be produced simultaneously in a radioactive beach environment.” – Zachary Adam, an astrobiologist at the University of Washington Seattle.

This is a hard theory to understand, it is well known that radioactivity breaks down organic molecules and causes a whole host of problems for us carbon-based creatures. But in the early Earth, devoid of plants and animals, radioactive processes may have provided energy for life to begin in the first place.

This theory also partially explains why life may be a very rare occurrence in the universe: there must be the correct concentration of radioactive elements, on the surface of a water-dominated developing planet, with tidal forces supplied by a closely orbiting stellar body. The Earth may, after all, be unique.

Source: Telegraph.co.uk

January 11, 2008December 26, 2015 by Fraser Cain

Red Dwarfs Have Teeny Tiny Habitable Zones

As space telescopes get larger and more sensitive, the search for Earth-sized worlds surrounding other stars is about to get rolling. But astronomers are going to need to know where to look. A team of researchers are working on a survey of nearby stars, calculating the habitable zones around them. When the search begins, astronomers are going to want to study these regions.

The Research Consortium on Nearby Stars (RECONS) is a survey using relatively small telescopes to study the habitable zones in the nearby stars. The team uses measurements of various stars brightnesses at optical and infrared wavelengths matched with their distances to get a sense of the stars’ habitability.

After gathering together a big list of potential candidate stars, the researchers can then categorize stars by size and temperature to find ones that might harbour life.

“Once we have good values for the temperatures and sizes of the nearby stars, we can estimate how hot planets will be at different distances from the stars,” explains Justin Cantrell, a Doctoral Candidate in Astronomy at Georgia State University. “We consider those stars that would have surface temperatures suitable for liquid water to be in the traditional habitable zone.”

The researchers were looking for habitable zones around red dwarf stars, which can be 50-90% smaller than the Sun and much cooler. The comprise 70% of the stars in the Milky Way, but they’re harder to spot because they put out less light.

They were surprised to learn that these red dwarf stars have tiny habitable zones. When they added up the habitable zones of 44 red dwarf stars nearby the Sun, they found they didn’t add up to equal the habitable zone of a single Sun like star.

So even though these red dwarfs are common, they’re not great candidates for life. Earth-type stars would need to be perfectly positioned in their tiny habitable zones to be good candidates for life.

Original Source: Georgia State University News Release

January 11, 2008December 26, 2015 by Fraser Cain

Gas Cloud on Collision Course with the Milky Way

Don’t panic, but there’s a giant cloud of hydrogen gas on a collision course with the Milky Way. When it hits, 40 million years from now, it should generate vast regions of star formation. In fact, we don’t even need to wait; the leading edge of this gas cloud is already starting to interact with our galaxy. The fireworks are about to begin.

The cloud is called Smith’s Cloud, after the astronomer who discovered it in 1963. It’s 11,000 light-years long and 2,500 light-years wide, and contains enough hydrogen to make a million stars with the mass of the Sun.

Felix J. Lockman, of the National Radio Astronomy Observatory (NRAO) announced their latest observations of Smith’s Cloud at the Winter meeting of the American Astronomical Society in Austin, Texas. According to Lockman, the cloud is located 8,000 light-years from the Milky Way’s disk, and hurtling towards us at 240 km/second (150 miles/second).

“This is most likely a gas cloud left over from the formation of the Milky Way or gas stripped from a neighbor galaxy. When it hits, it could set off a tremendous burst of star formation. Many of those stars will be very massive, rushing through their lives quickly and exploding as supernovae. Over a few million years, it’ll look like a celestial New Year’s celebration, with huge firecrackers going off in that region of the galaxy,” Lockman said.

Until this latest research, astronomers were never sure if Smith’s Cloud was actually part of the Milky Way, being blown out of the galaxy, or something falling in.

Lockman and his colleagues made 40,000 individual pointings of the Green Bank radio telescope to pull together the data for their observations. This was necessary because the cloud is so vast.

“If you could see this cloud with your eyes, it would be a very impressive sight in the night sky,” Lockman said. “From tip to tail it would cover almost as much sky as the Orion constellation. But as far as we know it is made entirely of gas – no one has found a single star in it.”

Original Source: NRAO News Release

January 11, 2008December 26, 2015 by Fraser Cain

Fat Black Holes Can Lurk in Thin Galaxies

Supermassive black holes are thought to lurk at the heart of most galaxies. Scientists have long believed that only the galaxies with thick central bulges could pull together enough mass for a supermassive black hole to form. But NASA’s Spitzer Space Telescope has turned up evidence that even skinny galaxies, with no central bulge, can still form these galactic monsters.

Astronomers used the Spitzer Space Telescope to survey 32 flat and bulgeless galaxies, and still turned up supermassive black holes in their central cores. This means that galaxy bulges aren’t necessary to build up these black holes; instead, the mysterious and invisible dark matter might be necessary to bring them together.

“This finding challenges the current paradigm. The fact that galaxies without bulges have black holes means that the bulges cannot be the determining factor, said Shobita Satyapal of George Mason University, presenting her research at the American Astronomical Society’s Winter meeting in Austin. “It’s possible that the dark matter that fills the halos around galaxies plays an important role in the early development of supermassive black holes.”

Seen from edge on, our own Milky Way’s bulge would be clearly visible, with the thin spiral arms trailing away to the sides. And researchers know we have a supermassive black hole. Researchers used to think there was a direct connection between the size of the bulge, and the mass of the black hole.

But in 2003, astronomers discovered a relatively lightweight black hole in a galaxy without a bulge. And then earlier this year, Satyapal and her team found another example of this bulgeless black hole.

Since bulges don’t seem to matter, Satyapal suggests that a galaxy’s dark matter halo is the deciding factor to determine how massive a black hole can get.

“Maybe the bulge was just serving as a proxy for the dark matter mass – the real determining factor behind the existence and mass of a black hole in a galaxy’s center,” said Satyapal.

Original Source: Spitzer News Release

January 11, 2008December 26, 2015 by Nicholos Wethington

MESSENGER Flyby of Mercury January 14th

If you thought you were good at pool, think again: in a game of interplanetary billiards, the MESSENGER team has guided its spacecraft to pass by Mercury for the first time on Monday, after a dizzying path that has already taken it past the Earth once and Venus twice.

The MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) spacecraft will make its very first flyby of the planet on January 14th at 2:04 EST. It will pass within 200 kilometers (124 miles) of the surface. During the flyby it will be taking images and scientific measurements of the planet’s features.

The data it will be taking this time around will complement the measurements it will make when finally in orbit. MESSENGER will map the composition of Mercury’s surface, capture images at a resolution of hundreds of meters, and measure the structure of the planet’s magnetosphere and magnetic and gravitational fields.

Monday’s flyby will be the first time a spacecraft has visited Mercury in 33 years, since Mariner 10 did a series of flybys in the mid-1970s. During that mission, the spacecraft only imaged one hemisphere of the planet. MESSENGER will complete the picture, so to speak, by taking close-up images for the very first time of the other hemisphere.

The flyby will allow the spacecraft to map several features of Mercury that it will not be able to measure when in orbit, such as the magnetotail â€“ the drawn out tail of the planet’s magnetosphere as it travels through space. It will also take over 1,200 images of the planet.

MESSENGER was launched in August of 2004, and has been making its way to Mercury by a number of different flybys of the Earth and Venus. The journey, though, is far from over. The spacecraft will make two more flybys of Mercury in October 2008 and September 2009, finally settling into orbit of the planet in March 2011.

It will then start a yearlong comprehensive study with its seven scientific instruments. When the journey is over, it will have traveled 4.9 billion miles (7.9 billion kilometers).

For more information and photos of the flyby, visit the official MESSENGER website.

Source: Johns Hopkins University Applied Physics Laboratory Press Release

January 11, 2008December 26, 2015 by Fraser Cain

Super-Neutron Stars are Possible

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When a star like our Sun dies, it’ll end up as a white dwarf. And if a star contains 1.4 times the mass of the Sun, it’ll have enough gravity to turn into a neutron star. Much bigger stars turn into black holes. But now it turns out, neutron stars can be much more massive than astronomers previously believed – and making black holes might be much more difficult.

Astronomers working with the Arecibo Observatory in Puerto Rico have increased the mass limit you need for a neutron star to turn into a black hole.

Paulo Freire, an astronomer from Arecibo presented his latest research at the Winter meeting of the American Astronomical Society, “the matter at the center of a neutron star is highly incompressible. Our new measurements of the mass of neutron stars will help nuclear physicists understand the properties of super-dense matter. It also means that to form a black hole, more mass is needed than previously thought. Thus, in our universe, black holes might be more rare and neutron stars slightly more abundant.

When these massive stars run out of fuel, they collapse down and then explode as a supernova. The core of the star is instantly compressed into a neutron star; an extreme object with a radius of roughly 10 to 16 km across and a density of billions of tonnes per cubic centimetre. A neutron star acts like a single, giant atomic nucleus.

Astronomers used to think that neutron stars needed between 1.6 and 2.5 times the mass of the Sun to collapse – any bigger and you’d get a neutron star. But the new evidence from Arecibo pushes this limit up to 2.7 times the mass of the Sun.

Although that sounds like a slight amount, it can actually have a significant impact on the ratio of neutron stars to black holes in the Universe.

In fact, scientists don’t fully understand how dense neutron stars can really be, and when they might actually switch over to become black holes, “the matter at the center of neutron stars is the densest in the Universe. It is one to two orders of magnitude denser than matter in the atomic nucleus. It is so dense we don’t know what it is made out of,” said Freire. “For that reason, we have at present no idea of how larger or how massive neutron stars can be.”

Original Source: Cornell University

January 10, 2008December 26, 2015 by Fraser Cain

Galaxy’s Arms are Rotating Backwards

As galaxies rotate, their spiral arms usually sweep back, trailing behind the rotation of the galaxy. But astronomers have found a galaxy that defies this convention, with its arms opening outward in the same direction as the rotation of the galaxy’s disk.

The galaxy, known as NGC 4622, lies 200 million light years away in the constellation Centaurus. A team of American astronomers analyzed images of the galaxy, and discovered that it has a previously hidden inner counter clockwise pair of spiral arms.

“Contrary to conventional wisdom, with both an inner counter-clockwise pair and an outer clockwise pair of spiral arms, NGC 4622 must have a pair of leading arms,” said Dr. Gene Byrd from the University of Alabama. “With two pairs of arms winding in opposite directions, one pair must lead and one pair must trail. Which way is which depends on the disk’s rotation. Alternatively, the inner counter clockwise pair must be the leading pair if the disk turns counter clockwise.”

This isn’t the first time the team announced their findings that NGC 4622 had a leading pair of spiral arms. Other astronomers were skeptical of the result, since the galaxy disk is only tilted 19 degrees from face-on, and clumpy clouds of dust could confuse the results.

The researchers came back and used two different independent techniques to verify the direction the arms are spinning.

Further observations are coming, since images from the Hubble Space Telescope revealed a dark dust lane in the centre of the galaxy. This suggests that NGC 4622 may have consumed a smaller companion galaxy, and this could help explain where the additional spiral arms came from.

Original Source: University of Alabama News Release

January 10, 2008December 26, 2015 by Fraser Cain

Death Echos of Material Destroyed Near a Black Hole

Greedy black holes can only consume so much material. The leftover matter backs up into an accretion disk surrounding the black hole. The pull of the black hole is so strong that flashes of radiation emitted from this accretion disk might need to make several orbits around the black hole before it can actually escape the gravitational pull. And these echoes might serve as a probe, allowing astronomers to understand the nature of the black hole itself.

Keigo Fukumura and Demosthenes Kazanas from NASA’s Goddard Space Flight Center revealed their theoretical research at the Winter meeting of the American Astronomical Society.

“The light echoes come about because of the severe warping of spacetime predicted by Einstein,” said Fukumura. “If the black hole is spinning fast, it can literally drag the surrounding space, and this can produce some wild special effects.”

Black holes are surrounded by a disk of searing hot gas rotating at close to the speed of light. A black hole can only consume material so quickly, so any additional matter backs up into this accretion disk. The material in these disks can form hot spots which emit random bursts of X-rays.

When the researchers accounted for the predictions made by Einstein’s general theory of relativity, they realized that the severe warp of spacetime can actually change the path X-rays take as they escape the grasp of the black hole. The X-rays can actually be delayed, depending on the position of the black hole, the position of the flare, and Earth.

If the black hole is rotating at the most extreme speeds, photons can actually make several orbits around the black hole before escaping.

“For each X-ray burst from a hot spot, the observer will receive two or more flashes separated by a constant interval, so even a signal made up from a totally random collection of bursts from hot spots at different positions will contain an echo of itself,” says Kazanas.

Astronomers watching these flashes will have a powerful observational tool they can use to probe the nature of the black hole. The frequency of the flashes would provide astronomers with an accurate way to measure the mass of the black hole.

Original Source: NASA News Release