THE coming week is a great time to look for planets. A new moon on 28 October means no moonlight and, with the exception of Neptune , every planet is visible at some point in the coming days. Even distant Uranus, which at 8 pm GMT on 27 October will be a mere 2.8 billion kilometres away.
Venus is the easiest to find, with an apparent magnitude of -4.6. In the magnitude scale, objects with lower numbers are brighter! Spot six planets in the sky this week: Mercury, Mars ...www.reddit.com /.../comments/dmdx7n/ ..._mercury Spot six planets in the sky this week : Mercury, Mars, Uranus and more. Close ...!! It is close to the sun, …
Quite a lot has been going on:
'Planet Nine' may actually be a black hole | Science | AAAS
For nearly 5 years, growing numbers of scientists have blamed the weird orbits of distant solar system objects on the gravitational effects of an as-yet-undiscovered "Planet Nine" that lies in the icy realm far beyond Neptune! Flipboard: Spot six planets in the sky this week: Mercury ...flipboard.com/article/ ...mars-uranus...Spot six planets in the sky this week : Mercury, Mars, Uranus and more | New Scientist. newscientist.com - By Abigail Beall. THE coming week is a great time to look for planets . A new moon on 28 October means no moonlight and, with the exception of Neptune, every planet is …!! But a pair of physicists is now floating an intriguing idea that could offer a new way to search for the object: What if that supposed planet is actually a small black hole?
Previous studies have suggested Planet Nine, which some astronomers refer to as "Planet X," has a mass between five and 15 times that of Earth and lies between 45 billion and 150 billion kilometers from the sun. At such a distance, an object would receive very little light from the sun, making it hard to see with telescopes.
To detect objects of that mass, whether planets or black holes, astronomers can look for weird blobs of light formed when light "bends" around the object's gravitational field on its journey through the galaxy (simulated image above). Those anomalies would come and go as objects move in front of a distant star and continue in their orbit.
Clan reunions and green planets
Astronomers discover a gigantic planet that should not exist - CNET
The confusion is around GJ 3512b and how large it is compared to the star it orbits, an M-type red dwarf. This kind of star is quite small, traditionally one-fifth the size of the sun and up to 50 times dimmer! Sky at a Glance | Recent Astronomy News & Night Sky Events www. sky ...a-glance See this week 's sky at a glance with observing tips and maps to guide you to the night sky . Don't miss out on comets, meteors, eclipses, and more!!! For comparison, our sun weighs roughly 333,000 times more than Earth, while GJ 3512b's star only weighs 270 times more. Jupiter, the largest planet in our solar system, weighs around 1,047 times less than the sun.
Planet GJ 3512b is around half the size of Jupiter, but even then, it's only around 250 times less massive than its star. This is weird! The Sky this Week | Astronomy.com www. astronomy .com/observing/ sky - this-week The Sky This Week from October 18 to 27 Hubble reveals that galaxies without dark matter really exist Ancient Middle Eastern astrologers recorded the oldest-known evidence of aurorae!! According to existing models, that makes GJ 3512b way too big to be orbiting an M-type red dwarf of this size.
Originally published 7:05 p.m. PT.
Correction, 10:55 p.m. PT: An earlier version of this article misstated the size of GJ 3512b's star. The star weighs 270 times more than the planet.
Not to change the topic here:
What moons in other solar systems reveal about planets like Neptune and Jupiter
Bradley Hansen does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
* * *
What is the difference between a planet-satellite system as we have with the Earth and Moon, versus a binary planet – two planets orbiting each other in a cosmic do-si-do?
In 2018, two astronomers from Columbia University reported the first tentative observation of an exomoon – a satellite orbiting a planet that itself orbits another star. One curious feature was that this exomoon Kepler-1625b-i was much more massive than any moon found in our solar system! October guide to the bright planets | Astronomy Essentials ...earthsky.org ...planets October guide to the bright planets Posted by Bruce McClure and Deborah Byrd in Astronomy Essentials | September 30, 2019 Only 2 of the 5 bright planets are easy to see in October 2019, but 2 ...!! It has a mass similar to Neptune and orbits a planet similar in size to Jupiter.
Astronomers expect moons of planets like Jupiter and Saturn to have masses only a few percent of Earth. But this new exomoon was almost a thousand times larger than the corresponding bodies of our solar system – moons like Ganymede and Titan which orbit Jupiter and Saturn, respectively. It is very difficult to explain the formation of such a large satellite using current models of moon formation.
Impact Bombardment Chronology of the Terrestrial Planets From 4.5 Ga to 3.5 Ga - Astrobiology
Subsequent to the Moon's formation, late accretion to the terrestrial planets modified their silicate crusts and mantles.
The background mass addition from small leftover planetesimals to Earth and Mars is far less than independent estimates based on their mantle abundances of highly-siderophile elements. This supports the theory that both planets were struck by single large bodies that delivered most of their mass augmentation since primary accretion. We present fits to the impact chronologies valid from 4500 Ma to ca. 3700 Ma.
The lunar timeline thus obtained is at odds with both the calibrated Neukum (Neukum et al., 2001) and Werner (Werner et al., 2014; Werner, 2019) chronologies. For Mars, the match with its calibrated Werner chronology is no better; by increasing the mass of the E-belt by a factor of four the dynamical lunar and martian chronologies are in line with that of Werner (2019) and match constraints from the current population of Hungaria asteroids. Yet, neither of our dynamical timelines fit well with that of Neukum. The dynamical lunar and martian chronologies are also different from each other. Consequently, the usual extrapolation of such chronologies from one planetary body to the other is technically inappropriate.
No comments:
Post a Comment