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  • May 9, 2017
  • 12:54 AM
  • 352 views

Quick Look: The Thermal Structure of the Venus Atmosphere

by Paul Wren in Venus Dispatches

SummaryFor two years beginning in 2013, a large team led by Sanjay Limaye set out to combine and compare the following:Venusian atmospheric data collected by probes in the 1970s and 1980s (used to create the Venus International Reference Atmosphere, or VIRA)Venus Express data on the vertical and horizontal structure of the atmosphereEarth-based observations of the upper atmosphere temperature structure of Venus made since VIRAFigure 1a: Vertical coverage of post-VIRA atmospheric structure experi........ Read more »

  • April 27, 2017
  • 12:33 AM
  • 264 views

Recently Active Lava Flows on Idunn Mons

by Paul Wren in Venus Dispatches

OverviewCombined VIRTIS emissivity and Magellan SAR image of Idunn MonsIn Idunn Mons on Venus: Location and extent of recently active lava flows, Piero D'Incecco and his colleagues looked closer at 1 µm thermal emissivity anomalies on the eastern flank of Idunn Mons, as observed by the VIRTIS instrument on Venus Express. Hypothesizing that recent lava flows were responsible, they overlayed the VIRTIS emissivity data with SAR images from the Magellan mission to look for lava flows that may have ........ Read more »

D'Incecco, P., Müller, N., Helbert, J., & D'Amore, M. (2017) Idunn Mons on Venus: Location and extent of recently active lava flows. Planetary and Space Science, 25-33. DOI: 10.1016/j.pss.2016.12.002  

  • April 21, 2017
  • 01:02 PM
  • 255 views

Spectral Guide for Earth-based Observers to Complement Akatsuki Mission

by Paul Wren in Venus Dispatches

OverviewMeant as a guide for Earth-based observers of Venus (professional and amateur), Overview of useful spectral regions for Venus: An update to encourage observations complementary to the Akatsuki mission provides detailed information regarding the wavelengths at which observations should be made to complement the Akatsuki mission at Venus.Two tables (one for day side observing, the other for night side) provide opportunities across a "spectrum" of wavelengths, indicating what products are l........ Read more »

  • April 18, 2017
  • 01:43 PM
  • 254 views

Bright highlands in equatorial Venus likely ferro-electric. What's up with the high-latitude highlands?

by Paul Wren in Venus Dispatches

OverviewA lot of papers have been written about the highly reflective highlands (in radar) on Venus, with several different hypotheses (e.g. high porosity, metal frost).  Allan Treiman, Elise Harrington, and Virgil Sharpton look specifically at high-latitude highlands in comparison to highlands in the equatorial regions.  Both areas feature high reflectivity, but the reflectance patterns are distinct, as they describe in Venus' radar-bright highlands: Different signatures and mate........ Read more »

  • April 17, 2017
  • 01:20 AM
  • 220 views

Discovery of a 150 day period in the Venus condensational clouds

by Paul Wren in Venus Dispatches

OverviewUsing near infrared (NIR) data from the VIRTIS instrument that once traveled aboard the Venus Express spacecraft, Kevin McGouldrick and Constantine C. C. Tsang found a periodic variation in radiance, most intense at the mid-latitudes.  The paper is here.What Did They Find?They identified A 150-day periodic variation in radiance within the 1.74 µm and 2.30 µm windows, which is most pronounced between 30° and 60° latitude.  They also found that in these mid-latitudes, ra........ Read more »

  • February 24, 2017
  • 12:06 PM
  • 537 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
  • 10:01 AM
  • 713 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
  • 10:02 AM
  • 747 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
  • 10:05 AM
  • 705 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
  • 10:02 AM
  • 673 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
  • 10:04 AM
  • 554 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
  • 11:38 AM
  • 589 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
  • 10:02 AM
  • 565 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
  • 10:04 AM
  • 524 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
  • 10:24 AM
  • 547 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
  • 10:21 AM
  • 1,086 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
  • 08:00 PM
  • 654 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
  • 06:02 AM
  • 1,172 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
  • 10:00 AM
  • 1,790 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
  • 02:22 AM
  • 1,091 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  

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