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  • February 24, 2017
  • 11:06 AM
  • 198 views

What if black holes were not... holes? A Los Alamos physicist explains his alternative theory behind these mysterious objects.

by EE Giorgi in CHIMERAS

© Elena E. GiorgiThe concept of a “black hole” — a celestial body so dense and massive that not even light can escape its gravitational field — dates back to the 18th century, with the theoretical work of Pierre-Simon Laplace and John Michell. But it wasn’t until the early 20th century that these mysterious dark objects were first described mathematically by German physicist Karl Schwarzschild. Schwarzschild’s work predicted the existence of a finite distance around the black hole (........ Read more »

Mazur, P., & Mottola, E. (2004) Gravitational vacuum condensate stars. Proceedings of the National Academy of Sciences, 101(26), 9545-9550. DOI: 10.1073/pnas.0402717101  

Emil Mottola. (2010) New Horizons in Gravity: The Trace Anomaly, Dark Energy and Condensate Stars. Acta Physica Polonica B (2010) Vol.41, iss.9, p.2031-2162. arXiv: 1008.5006v1

  • November 1, 2016
  • 09:01 AM
  • 464 views

Multiwavelength study of 20 jets that emanate from the periphery of active regions by Sargam M. Mulay et al.*

by CESRA in Solar Radio Science

Solar jets are transient phenomena observed in the solar atmosphere. They appear as sharp-edged, impulsive, and collimated flows of plasma that move outwards with a bright spot at the footpoint, which forms an ‘inverted-Y’ topology of magnetic field lines. They are observed throughout the atmosphere i.e. in the photosphere (Hα, Ca II K [...]... Read more »

Mulay et al. (2006) Multiwavelength study of 20 jets that emanate from the periphery of active regions. Astronomy . info:/

  • October 18, 2016
  • 09:02 AM
  • 487 views

Decameter type III bursts with changing frequency drift-rate signs by V. Melnik et al.*

by CESRA in Solar Radio Science

We discuss properties of type III bursts that change the sign of their drift rate from negative to positive and vice versa. Moreover, these bursts may change the sign of their drift rates more than once. These particular type III bursts were observed simultaneously by the radio telescopes UTR-2, URAN-2, [...]... Read more »

V. Melnik et al. (2015) Decameter type III bursts with changing frequency drift-rate signs . Solar Physics. info:/

  • October 4, 2016
  • 09:05 AM
  • 486 views

Propagation of Coronal Mass Ejections: Aerodynamic Drag by Nishtha Sachdeva and Prasad Subramanian

by CESRA in Solar Radio Science

Coronal Mass Ejections (CMEs) are hot, massive blobs of plasma and magnetic fields that erupt from the Sun, and are sometimes Earth-directed. Depending on their speed and mass these transients can strongly effect the space weather, causing geomagnetic storms and damage to space bound technologies. It is therefore imperative to [...]... Read more »

Sachdeva, N., Subramanian, P., Colaninno, R., et al.,. (2015) Propagation of Coronal Mass Ejections: Aerodynamic Drag. Astrophysical Journal, 158. info:/

  • September 13, 2016
  • 09:02 AM
  • 472 views

An Analysis of Interplanetary Solar Radio Emissions Associated with a Coronal Mass Ejection by V. Krupar et al.*

by CESRA in Solar Radio Science

Type II and type III bursts are generated, via the plasma emission mechanism, when beams of suprathermal electrons interact with the ambient plasma generating radio emissions at the plasma frequency fp (the fundamental emission) or at its second harmonic 2fp (the harmonic emission) [see also previous CESRA highlights here and [...]... Read more »

V. Krupar et al. (2016) An Analysis of Interplanetary Solar Radio Emissions Associated with a Coronal Mass Ejection. Astrophys. J. Lett., 823, L5. info:/

  • August 30, 2016
  • 09:04 AM
  • 386 views

On the thermal nature of 140 GHz emission from the 4 July 2012 solar flare by Yuriy Tsap et al.*

by CESRA in Solar Radio Science

The nature of the solar flare sub-THz emission (Kaufmann, 2012) with a positive spectral slope at 200-400 GHz is still not clear..... Read more »

Yuriy Tsap et al.*. (2016) On the thermal nature of 140 GHz emission from the 4 July 2012 solar flare. Advances in Space Research, 2016, 57, 1449. info:/

  • August 29, 2016
  • 10:38 AM
  • 424 views

Ancient Mars was warm and wet, suggest UCL-led research team

by vitul in Think, Ask and Resolve

After the recent discovery of extensive fossilised riverbeds on Mars, the idea that the Red Planet could have been habitable 4 billion years ago has gained more traction.... Read more »

  • August 23, 2016
  • 09:02 AM
  • 403 views

Bright 30 THz impulsive solar bursts by Pierre Kaufmann et al.*

by CESRA in Solar Radio Science

Impulsive 30 THz continuum bursts have been recently observed in solar flares, utilizing small telescopes with a unique and relatively simple optical setup concept (Kaufmann et al. 2015). The most intense burst was observed together with a GOES X2 class event on October 27, 2014, also detected at two sub-THz [...]... Read more »

Pierre Kaufmann et al. (2016) Bright 30 THz impulsive solar bursts . Journal of Geophys. Res. info:/

  • August 16, 2016
  • 09:04 AM
  • 369 views

Decameter U-burst Harmonic Pair from a High Loop by Dorovskyy, Melnik, Konovalenko, Bubnov , Gridin, Shevchuk, Rucker, Poedts and Panchenko

by CESRA in Solar Radio Science

We discuss the results of recent observations of a solar U-burst harmonic pair in the frequency range 10-70 MHz, performed by the radio telescope UTR-2 ...... Read more »

Dorovskyy et al. (2016) Decameter U-burst Harmonic Pair from a High Loop by Dorovskyy et al. Solar Physics. info:/

  • August 9, 2016
  • 09:24 AM
  • 383 views

Particle Acceleration and heating by turbulent reconnection by L. Vlahos, T. Pisokas, H. Isliker, V. Tsiolis and A. Anastasiadis

by CESRA in Solar Radio Science

Fermi (1949) introduced a fundamental stochastic process to solve the problem of particle energization (heating and/or acceleration) in space and astrophysical plasmas. The initial idea of Fermi with randomly moving scatterers (magnetic clouds), was soon replaced with a spectrum of low amplitude (δΒ/Β... Read more »

by L. Vlahos, T. Pisokas, H. Isliker, V. Tsiolis and A. Anastasiadis. (2016) Particle Acceleration and heating by turbulent reconnection. ApJ. info:/

  • May 13, 2016
  • 09:21 AM
  • 770 views

Using Supercomputers to Probe the Early Universe

by EE Giorgi in CHIMERAS

Artist's depiction of the WMAP satellite gathering data to understand the Big Bang. Source: NASA.For decades physicists have been trying to decipher the first moments after the Big Bang. Using very large telescopes, for example, scientists scan the skies and look at how fast galaxies move. Satellites study the relic radiation left from the Big Bang, called the cosmic microwave background radiation. And finally, particle colliders, like the Large Hadron Collider at CERN, allow researchers to smas........ Read more »

  • February 14, 2016
  • 07:00 PM
  • 518 views

Quixotic Science

by Paco Jariego in Mind the Post

Almost all science stems from a need to explain what we see. Not general relativity. What comes first, theory or technology? a reflection after LIGO has detected gravitational waves.... Read more »

The LIGO Scientific Collaboration, & the Virgo Collaboration. (2016) Observation of Gravitational Waves from a Binary Black Hole Merger. Phys. Rev. Lett. 116, 061102 (2016). arXiv: 1602.03837v1

  • February 13, 2016
  • 05:02 AM
  • 986 views

Now we can hear the Universe

by TakFurTheKaffe in Tak Fur The Kaffe

The detection of gravitational waves produced by the collision of two black holes over 1 billion light years away confirms Einstein's vision of our Universe.... Read more »

Abbott, B., Abbott, R., Abbott, T., Abernathy, M., Acernese, F., Ackley, K., Adams, C., Adams, T., Addesso, P., Adhikari, R.... (2016) Observation of Gravitational Waves from a Binary Black Hole Merger. Physical Review Letters, 116(6). DOI: 10.1103/PhysRevLett.116.061102  

  • September 17, 2015
  • 09:00 AM
  • 1,560 views

The Martian: Getting Home Is Just Half The Problem

by Mark Lasbury in The 'Scope

"The Martian" movie opens soon! It's about an astronaut stranded on Mars who is trying to survive and find a way to get back home. But today, we humans here on Earth still have to think of clever ways to survive a trip to the red planet in the first place.... Read more »

  • August 6, 2015
  • 01:22 AM
  • 956 views

Best evidence yet for active volcanism on Venus?

by Paul Wren in Venus Dispatches

OverviewIn an article from Geophysical Research Letters, a team led by Eugene Shaygin used images taken by the Venus Monitoring Camera (VMC) aboard Venus Express to identify transient hot spots on the surface. These hot spots are located near very young (~10 Mya) volcanoes and rifts, and are suggestive of active lava flows.Even though the surface is generally obscured from view by the thick clouds, there is a transparent window through which light can pass in the near infrared wavelengths, and t........ Read more »

Shalygin, E., Markiewicz, W., Basilevsky, A., Titov, D., Ignatiev, N., & Head, J. (2015) Active volcanism on Venus in the Ganiki Chasma rift zone. Geophysical Research Letters, 42(12), 4762-4769. DOI: 10.1002/2015GL064088  

  • August 5, 2015
  • 12:51 AM
  • 893 views

Quick Look: Vertical profiles of H2O, H2SO4, and sulfuric acid concentration at 45–75 km on Venus

by Paul Wren in Venus Dispatches

An improved model for vertical profiles of water and sulfuric acid vapors as well as sulfuric acid concentrations in the Venus clouds is presented. From the April 2015 edition of Icarus:Title:Vertical profiles of H2O, H2SO4, and sulfuric acid concentration at 45–75 km on VenusAbstract:A method developed by Krasnopolsky and Pollack (Krasnopolsky, V.A., Pollack, J.B. [1994]. Icarus 109, 58–78) to model vertical profiles of H2O and H2SO4 vapors and sulfuric acid concentration in the Venus cloud........ Read more »

  • July 20, 2015
  • 11:05 AM
  • 968 views

Quick Look: Touchdown on Venus: Analytic Wind Models and a Heuristic Approach to Estimating Landing Dispersions

by Paul Wren in Venus Dispatches

I'm working through a lot of recent Venus-related papers, so here's another morsel for you that I will not have time to read in depth (I'm prioritizing articles relating to the Venusian surface). The author created a straightforward model of winds on Venus (using data from the VEGA Balloons and the Pioneer descent probes) to determine entry and descent dispersions for future Venus landers. From the April 2015 edition of Planetary and Space Science:Title:Touchdown on Venus: Analytic wind models ........ Read more »

  • July 10, 2015
  • 01:23 AM
  • 745 views

Quick Look: Computer model shows imaging of Venus surface possible from balloon

by Paul Wren in Venus Dispatches

From the April 2015 edition of Solar System Research:Title:Resolving the surface details on Venus in the balloon- or lander-borne images with a computer modeling methodAbstract:Due to the presence of opaque clouds at high altitudes, it is difficult to survey the surface of Venus in the optical spectral range. At the same time, in the under-cloud layer, there are transparency windows at the wavelengths λ = 1.08, 0.85, and 0.65 μm. At these wavelengths, the gaseous absorption (in the whole atmos........ Read more »

  • July 9, 2015
  • 01:22 AM
  • 869 views

Impact Crater Ejecta Mantling on Venusian Tesserae? Earth-based Radar Seems to Say Yes

by Paul Wren in Venus Dispatches

OverviewThe Smithsonian's Bruce Campbell and his colleagues (Campbell et al., 2015) combined radar imagery captured in 1988 and 2012 by the Arecibo and Greenbank radio telescopes to better detect the parabola-shaped deposits of impact crater ejecta on Venus. They were looking for such deposits on the highly-deformed terrain of tessera regions, which are suspected of having formed at a time when there was still water on the surface.Previous researchers had identified large parabolic deposits of ........ Read more »

  • June 14, 2015
  • 12:05 AM
  • 962 views

Pluto and Planetary Pinball

by Angela Reisetter in Steeped in Science

A description of the formation of the solar system and how we think it got to be how it is today, with a focus on Pluto and Kuiper belt.... Read more »

Thayne Currie, Carey M. Lisse, Marc J. Kuchner, Nikku Madhusudhan, Scott J. Kenyon, Christian Thalmann, Joseph Carson, & John H. Debes. (2015) Direct Imaging and Spectroscopy of a Young Extrasolar Kuiper Belt in the Nearest OB Association. Astrophysical Journal Letters. arXiv: 1505.06734v1

Konstantin Batygin, & Gregory Laughlin. (2015) Jupiter's Decisive Role in the Inner Solar System's Early Evolution. Proceedings of the National Academy of Sciences. arXiv: 1503.06945v2

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