A presentation I gave to the Brighton Astronomy Society in Jan 2016 - http://brightonastro.com/ , https://www.facebook.com/brightonastro/
Annoyingly that's removed the videos from the slides, so here are links to those:
https://www.youtube.com/watch?v=e-P5IFTqB98&t=18s
(This Youtube channel "In a nutshell" is absolutely fantastic by the way and I highly recommend a look through their other videos!)
https://www.youtube.com/watch?v=duoHtJpo4GY
https://vimeo.com/8723702
I've also made my notes from preparing the slides available here as well:
https://docs.google.com/document/d/1gqgsAbvoCB_7-_gPToqOuSixc02YnU-ajf-uT60R1vc/edit?usp=sharing
-- there are LOTS of further links to interesting videos in there as well, that I didn't use on the night so worth a scan through.
Any further questions, feel free to ask in comments on here
Hey I'm DIVYA SHREE NANDINI. I'm here with my new presentation on Black Hole. I'm sure you'll find it interesting. well first thing what is black hole- "Black hole, cosmic body of extremely intense gravity from which nothing, not even light, can escape. A black hole can be formed by the death of a massive star. When such a star has exhausted the internal thermonuclear fuels in its core at the end of its life, the core becomes unstable and gravitationally collapses inward upon itself, and the star’s outer layers are blown away. The crushing weight of constituent matter falling in from all sides compresses the dying star to a point of zero volume and infinite density called the singularity." wanna know more about it then come with me. :)
Hey I'm DIVYA SHREE NANDINI. I'm here with my new presentation on Black Hole. I'm sure you'll find it interesting. well first thing what is black hole- "Black hole, cosmic body of extremely intense gravity from which nothing, not even light, can escape. A black hole can be formed by the death of a massive star. When such a star has exhausted the internal thermonuclear fuels in its core at the end of its life, the core becomes unstable and gravitationally collapses inward upon itself, and the star’s outer layers are blown away. The crushing weight of constituent matter falling in from all sides compresses the dying star to a point of zero volume and infinite density called the singularity." wanna know more about it then come with me. :)
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
This is a presentation on Black Holes.
This covers following data about Black Hole->
>>What is Black Hole.
>>History.
>>Parts of Black Hole.
>>Classification.
>>Closest Black Hole.
>>Largest Black Hole.
It is said that fact is sometimes stranger than fiction, and nowhere is this more true than in the case of black holes. Black holes are stranger than anything dreamt up by science fiction writers, but they are firmly matters of science ~fact.
search on NASA site also go through the latest news related to black holes before presenting your seminar.
many queries are asked related to black holes.
present the astronomical data's for Good delivery of seminar.In the 18th century John Michell and Pierre-Simon Laplace first mentioned about the objects with a huge gravitation, from which even light cannot escape.
In 1915 Albert Einstein developed the theory of general relativity.
Karl Schwarzschild finds black holes as a solution to Einstein’s equations (1916)
Robert Oppenheimer and Hartland Snyder predict that massive stars can collapse into black holes (1939)
A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull.”
Black holes are exotic structures whose gravitational fields are so powerful that they trap everything, even light. They were first postulated by Albert Einstein's theory of general relativity.”
This can happen when a star is dying.
Though they are black they are invisible to us.
The density of a black hole is so great it would be like taking the whole Earth and crushing into a volume smaller than a 1” marble!.
Stellar-mass: 3 to 20 times the mass of our Sun
Supermassive: Black holes with millions to billions of times the mass of our Sun
Mid-mass: In between stellar-mass and supermassive.
Detail about Black holes. It's definition, components and then history of black hole and General theory of relativity.
Life cycle of a star and formation of black hole in space.
Different types of choice after star's life end.
Different types of Black hole on basis on mass of Parent star. and classification of black holes on basis of charge and rotational motion of black holes. Quantum theory of physics.
Study of Black holes using Quantum mechanics by Steaphen Hawking.
Current research on black holes.
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
This is a presentation on Black Holes.
This covers following data about Black Hole->
>>What is Black Hole.
>>History.
>>Parts of Black Hole.
>>Classification.
>>Closest Black Hole.
>>Largest Black Hole.
It is said that fact is sometimes stranger than fiction, and nowhere is this more true than in the case of black holes. Black holes are stranger than anything dreamt up by science fiction writers, but they are firmly matters of science ~fact.
search on NASA site also go through the latest news related to black holes before presenting your seminar.
many queries are asked related to black holes.
present the astronomical data's for Good delivery of seminar.In the 18th century John Michell and Pierre-Simon Laplace first mentioned about the objects with a huge gravitation, from which even light cannot escape.
In 1915 Albert Einstein developed the theory of general relativity.
Karl Schwarzschild finds black holes as a solution to Einstein’s equations (1916)
Robert Oppenheimer and Hartland Snyder predict that massive stars can collapse into black holes (1939)
A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull.”
Black holes are exotic structures whose gravitational fields are so powerful that they trap everything, even light. They were first postulated by Albert Einstein's theory of general relativity.”
This can happen when a star is dying.
Though they are black they are invisible to us.
The density of a black hole is so great it would be like taking the whole Earth and crushing into a volume smaller than a 1” marble!.
Stellar-mass: 3 to 20 times the mass of our Sun
Supermassive: Black holes with millions to billions of times the mass of our Sun
Mid-mass: In between stellar-mass and supermassive.
Detail about Black holes. It's definition, components and then history of black hole and General theory of relativity.
Life cycle of a star and formation of black hole in space.
Different types of choice after star's life end.
Different types of Black hole on basis on mass of Parent star. and classification of black holes on basis of charge and rotational motion of black holes. Quantum theory of physics.
Study of Black holes using Quantum mechanics by Steaphen Hawking.
Current research on black holes.
Astronomy - White Dwarfs_Neutron Stars_Black Holes.pptxcstrohsnitter1
Basic overview of what happens when stars die. This presentation covers white dwarfs, electron degeneracy pressure, neutron stars, neutron degeneracy pressure, black holes, event horizons and singularities
Brighton Astro - Neutron Star PresentationGareth Jenkins
Presentation from 28th March 2017 to Brighton Astro group. Slideshare removes embedded videos, so two in here are the following:
https://www.youtube.com/watch?v=e-P5IFTqB98&t=18s
https://www.youtube.com/watch?v=NhOVDDiSvMM
Astronomy - State of the Art - GalaxiesChris Impey
Astronomy - State of the Art is a course covering the hottest topics in astronomy. In this section, the properties of galaxies are discussed, including supermassive black holes and dark matter.
Big Bang Theory & Other Recent Sciences || 2014 - Dr. Mahbub Khaniqra tube
RECENT SCIENCES
Big Bang, Dark Matter, Dark Energy, Black Hole, Neutrino, God Particle, Higgs Field, Graviton, Expansion of Universe, and Search for Life elsewhere in the Cosmos
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
9. SMALLER STARS (LIKE OUR SUN)
( Don’t worry, we have around 5
billions years left yet … )
10.
11. CHANDRASEKHAR LIMIT
• Discovered by Subrahmanyan Chandrasekhar
• Awarded Nobel Prize for Physics 1983
• Maximum mass of stable white dwarf
• 1.4 x mass of our Sun
• Above that – Neutron star or Black Hole
12. TOLMAN–OPPENHEIMER–VOLKOFF LIMIT
• Calculated in 1939, derived from similar
equations to the Chandrasekhar limit
• Maximum mass of neutron star
• 2 - 3 x mass of our Sun ( from core remnant )
• Original star mass 15 – 20 solar masses
• Above that – Black Hole
13. ALL ABOUT MASS OF CORE REMNANT
< 1.4 Solar Masses = White dwarf
1.4 - ~3 Solar Masses = Neutron star
> 3 Solar Masses = Black hole
14. MASS OF ORIGINAL STAR
< 10 Solar masses = White dwarf
10 – 29 Solar masses = Neutron star
> 29 Solar masses = Black hole
15. SOME OTHER SCENARIOS….
• Some stars may just vanish to black hole instantly
• Some huge stars blow up entirely, leaving NOTHING
• Some may form Quark Stars
16. NEUTRON STAR
• All empty space of atoms squeezed away
• Density of an atom core
• Tight structure of neutrons
• Matchbox of material = 13m tonnes
• Cube of Earth 135m square
17. BLACK HOLE
• Core completely collapses in on itself
• Mass compacts down to singularity
• Infinite density
• 1 dimension only
• More on this soon…
• Event Horizon – giving black hole its name
19. NON ROTATING BLACK HOLE
• “Schwarzschild Black Hole”
• No spin, no electric charge
20. SINGULARITY
• Infinite density
• 1 dimension – no real “size”
• Space-time curves infinitely
• Physics (esp relativity) breaks down entirely
• Combined quantum & relatively MAY explain one day
• No information can ever escape from singularity
21. EVENT HORIZON
• Shwarzschild radius – light can’t escape
• = Event Horizon
• No information can ever escape
• ( Except Hawking radiation! )
• Past this boundary, space time curves inwards
ONLY
28. • Inner / outer horizon
• Static Limit
• ”Location at which space-time is flowing at
the speed of light, making stationary
particles that would be travelling at the
speed of light”
• Ergosphere – region between the two
ROTATING BLACK HOLE
30. • Strong gravity bends light
• Large scales, gravitational
lensing of distant galaxies
• Similar around black holes
• Interstellar
GRAVITATIONAL LIGHT DISTORTION
31. • Too close to event horizon, yes
• At more distance, same pull as
original star
• Replacing Sun with black hole
NOT VORACIOUS VACUUM CLEANERS!
32. • Micro
• Solar Mass
• Intermediate Mass
• Super Massive
TYPES OF BLACK HOLE
33. • Micro:
TYPES OF BLACK HOLE
• Theoretical, never observed
• May have been created shortly after Big Bang
• May be created in particle accelerators
• Exist for 10th of trillionth of trillionth seconds
34. • Solar Mass:
TYPES OF BLACK HOLE
• Ghost of massive stars
• Size range approx 5 – 64 solar masses
• ~ 100m within our galaxy, mostly invisible
• Observable when in binary pair with star
• Nearest 1600 light years away
41. • 2 ly = 51Bn Km
• Nearest star is 37 tr Km
• Fits in 730 times!
MILKY WAY CENTRE – SAGITTARIUS A*
42. • Event horizon estimate 44 M km
• 75% of distance of Mercury to Sun
• Mass 4m Solar masses
• Event Horizon Telescope – imminent!!
MILKY WAY CENTRE – SAGITTARIUS A*
43. • Avg – 0.1% mass of galaxy
• Largest in relation to galaxy 4% – 14%!
SUPERMASSIVE BLACK HOLES
44.
45.
46.
47. • Scientists not yet sure
• Early galaxy gas clouds collapse
• Stellar black hole eats and enlarge
• Clusters of stellar holes combine
• Merging of galaxies combines cores
• Mystery how so big so early!
HOW FORMED?
48. • Ancient and distant
• 12 billion light years away
• Universe 1.8 bn years old
• But ENORMOUSLY bright!
• Dust/Gas rich early galaxies,
accretion disks
• > 200,000 known
• Blasars are where jets point
at us!
QUASARS & BLASARS
49. GRAVITATIONAL WAVES
• Orbiting and merging of
black holes
• Proposed by Einsten 1916
• Detected LIGO 2015
• Two 30 solar mass black
holes merging
50. GRAVITATIONAL WAVES
• eLISA – coming 2030!
maybe…..
• Pathfinder sent 2015
• Detect supermassive BH
mergers in early Universe
• Observe 25k compact
binaries in Milky Way
