© YouTube/Meteors
The luminous phenomenon began on the province of Jaén, at a height of about 120 km above sea level, and ended at an altitude of about 75 km.
Fireballs
The luminous phenomenon began on the province of Jaén, at a height of about 120 km above sea level, and ended at an altitude of about 75 km.
© Meteors (CAHA)
© Rolando Ligustri
New Comet ASASSN1 (C/2017 O1) already glows aqua from carbon-laced gases. The comet is currently visible in the pre-dawn sky through modest-sized telescopes.
New Comet ASASSN1 (C/2017 O1) already glows aqua from carbon-laced gases. The comet is currently visible in the pre-dawn sky through modest-sized telescopes.
The 15th-magnitude object was caught before dawn on July 19th in the constellation Cetus using data from the quadruple 14-cm "Cassius" telescope on Cerro Tololo, Chile. Don't be put off by that magnitude. The comet has brightened quickly in the past few days; visual observers are now reporting it at around magnitude +10 with a large (7′), weakly condensed coma. Chris Wyatt of Australia relates that a Swan band filter does a great job enhancing the apparent brightness and contrast of the coma, a sign this is a "gassy" comet.
© Stellarium
This wide-view map shows Comet ASASSN1's location at the Cetus–Eridanus border south of Alpha (α) Ceti (Menkar) on July 26th.
This wide-view map shows Comet ASASSN1's location at the Cetus–Eridanus border south of Alpha (α) Ceti (Menkar) on July 26th.
© Earth Sky
Artist’s concept of an asteroid passing near Earth.
Artist’s concept of an asteroid passing near Earth.
This means the asteroid's closest approach occurred 2.5 to 3 days before it was seen. Asteroid 2017 OO1 flyby had passed at about one-third the Earth-moon distance, or about 76,448 miles (123,031 km).
Although that's still a safe distance, a fact that stands out is that asteroid 2017 OO1 is about three times as big as the house-sized asteroid that penetrated the skies over Chelyabinsk, Russia in February, 2013, breaking windows in six Russian cities and causing more that 1,000 people to seek treatment for injuries, mostly from flying glass.
© NASA/JPL-Caltech
"The number of comets speaks to the amount of material left over from the solar system's formation," said James Bauer, lead author of the study and now a research professor at the University of Maryland, College Park. "We now know that there are more relatively large chunks of ancient material coming from the Oort Cloud than we thought."
Comets that take more than 200 years to make one revolution around the Sun are notoriously difficult to study. Because they spend most of their time far from our area of the solar system, many "long-period comets" will never approach the Sun in a person's lifetime. In fact, those that travel inward from the Oort Cloud -- a group of icy bodies beginning roughly 186 billion miles (300 billion kilometers) away from the Sun -- can have periods of thousands or even millions of years.
This illustration shows how scientists used data from NASA's WISE spacecraft to determine the nucleus sizes of comets. They subtracted a model of how dust and gas behave in comets in order to obtain the core size.
CBET nr. 4414, issued on 2017, July 24, announces the discovery of a comet (magnitude ~15.3) in the course of the "All-Sky Automated Survey for Supernovae" (ASASSN) program, from images taken with the 14-cm "Cassius" survey telescope at Cerro Tololo on July 19.32 UT. The new comet has been designated C/2017 O1.
I performed follow-up measurements of this object, while it was still on the neocp. Stacking of 10 unfiltered exposures, 60 seconds each, obtained remotely on 2017, July 23.7 from Q62 (iTelescope network) through 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet with a sharp central condensation surrounded by diffuse coma about 3 arcmins in diameter.
My confirmation image (click on it for a bigger version)
Below you can see the discovery image by ASASSN survey
I performed follow-up measurements of this object, while it was still on the neocp. Stacking of 10 unfiltered exposures, 60 seconds each, obtained remotely on 2017, July 23.7 from Q62 (iTelescope network) through 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer, shows that this object is a comet with a sharp central condensation surrounded by diffuse coma about 3 arcmins in diameter.
My confirmation image (click on it for a bigger version)
© Remanzacco Blogspot
YouTube/Exoss Citizen Science (screen capture)
© Zloyel/iStock
Sixty-five million years ago, just such an event killed off 75% of species on Earth. But to really wipe life off the planet, it would take an astrophysical event so powerful that Earth's oceans would literally boil away, according to a new study. The heat and cosmic radiation would make Earth inhospitable even to tardigrades, among the hardiest organisms ever discovered.
"They've taken a grand question—how resilient is life?—and turned [it] into a well-posed calculation, by focusing on the energy required to boil Earth's oceans," says Joshua Winn, an exoplanets expert at Princeton University, who was not involved in the study. "It's an awful lot of energy."
© EPTV
Photo of the Observatory of Campinas shows meteor trajectory in the sky
Photo of the Observatory of Campinas shows meteor trajectory in the sky
The Municipal Observatory of Campinas (SP) caught the passage of a meteor in the region on Thursday night (July 13th). The cameras captured the moment when a luminous ball appears in the sky. See the meteor's trajectory in the video above. Residents reported feeling the shaking walls and windows and a loud noise.
Astronomer Júlio Lobo explains that "When a meteor falls and explodes, it causes a sonic boom, which usually shakes the walls and windows. [...] When this happens, it produces a meteorite, which is the 'pebble' that will stay on the ground. So if anyone happened to see a falling meteor, communicate us because this is of great scientific importance".
According to the astronomer, the Campinas observatory currently has six cameras, and this is the largest number of cameras in a Brazilian observatory. Many other meteors were recorded on Thursday night.
"We recorded 88 meteors on the same night. There is a network that studies this officially," said the astronomer.
© American Meteor Society
The American Meteor Society received about 50 reports about a fireball seen over the Southeast late Thursday night. This map shows places that reported seeing the fireball.
The American Meteor Society received about 50 reports about a fireball seen over the Southeast late Thursday night. This map shows places that reported seeing the fireball.
AMS said the fireball was seen shortly after 10 p.m. in North Carolina, South Carolina, Alabama, Tennessee, Georgia, Virginia and Kentucky and Tennessee.
Because there was nothing other than the fireball reported in the area at the time of the boom, speculation is that the boom was likely a meteor breaking up in the atmosphere.
Click here to see the AMS report.
Comment: It is well worth remembering what can come out of the sky, without any warning at all, like the Chelyabinsk meteor fireball.
Even NASA's own space data supports citizens' recent observations, namely the inconvenient fact that meteor fireballs are increasing dramatically.