Next week’s night sky:
Wednesday marks the new moon. This is a great time for stargazing because the moon will not blot out any stars! Look out for the Pleiades high in the sky, one of the most beautiful star clusters of the night sky.
Hubble’s Beautiful Galaxy collisions
To celebrate a new year, the NASA/ESA Hubble Space Telescope has published a montage of six beautiful galaxy mergers. Each of these merging systems was studied as part of the recent HiPEEC survey to investigate the rate of new star formation within such systems. These interactions are a key aspect of galaxy evolution and are among the most spectacular events in the lifetime of a galaxy.
It is during rare merging events that galaxies undergo dramatic changes in their appearance and in their stellar content. These systems are excellent laboratories to trace the formation of star clusters under extreme physical conditions.
Most Complete type la supernova
Type Ia supernovae, as cosmological distance indicators, have led to the discovery of the accelerating expansion of the Universe. Nevertheless, the nature of their progenitors and explosion mechanisms remain unsolved mysteries.
An international team led by Dr. Wang Lingzhi from the Chinese Academy of Sciences South America Center for Astronomy (CAS-SACA)/China-Chile Joint Center for Astronomy (CCJCA) investigated a nearby Type Ia supernova SN 2017cbv and obtained the most complete light curve template and spectral template of a single supernova.
With this unique data set, researchers are able to set constraints on the nickel mass synthesized during the explosion, construct the SN explosion model that best fit the data, as well as to derive an upper limit of 0.1 solar mass for the mass of hydrogen. This simply means that researchers will understand star-forming much better.
To learn more, go here: https://iopscience.iop.org/article/10.3847/1538-4357/abba82
An extraordinary magnetar
Magnetars are a type of neutron star, an incredibly dense object mainly made up of tightly packed neutron, which forms from the collapsed core of a massive star during a supernova.
What sets magnetars apart from other neutron stars is that they also have the most powerful known magnetic fields in the universe. For context, the strength of our planet’s magnetic field has a value of about one Gauss, while a refrigerator magnet measures about 100 Gauss. Magnetars, on the other hand, have magnetic fields of about a million billion Gauss. If a magnetar was located a sixth of the way to the Moon (about 40,000 miles), it would wipe the data from all of the credit cards on Earth.
Chandra’s observations of J1818.0-1607 obtained less than a month after the discovery with Swift gave astronomers the first high-resolution view of this object in X-rays. The Chandra data revealed a point source where the magnetar was located, which is surrounded by diffuse X-ray emission, likely caused by X-rays reflecting off dust located in its vicinity. (Some of this diffuse X-ray emission may also be from winds blowing away from the neutron star.)
The explosion that created a magnetar of this age would be expected to have left behind a detectable debris field. To search for this supernova remnant, Safi-Harb and Blumer looked at the X-rays from Chandra, infrared data from Spitzer, and the radio data from the VLA. Based on the Spitzer and VLA data they found possible evidence for a remnant, but at a relatively large distance away from the magnetar. In order to cover this distance, the magnetar would need to have traveled at speeds far exceeding those of the fastest known neutron stars, even assuming it is much older than expected, which would allow more travel time.
To learn more, go here: https://iopscience.iop.org/article/10.3847/2041-8213/abc6a2
Do you have any cool astronomy research news from this week? Share it in the comments below!