खगोल विज्ञान
Orbital mechanics, cosmology, planetary science, astrophotography, and space exploration calculators.
कक्षीय अवधि कैलकुलेटर
Calculate the orbital period of a body circling a central mass using Kepler's relation T = 2pi * sqrt(a^3 / (G * M)).
कक्षीय वेग कैलकुलेटर
Determine the orbital speed of a body in a circular orbit using v = sqrt(G * M / r).
पलायन वेग कैलकुलेटर
Calculate the minimum speed needed to escape a celestial body's gravitational pull using v_esc = sqrt(2 G M / r).
गुरुत्वाकर्षण त्वरण कैलकुलेटर
Compute the surface gravitational acceleration of a celestial body from its mass and radius using g = G M / r^2.
केप्लर का तीसरा नियम कैलकुलेटर
Relate orbital period and semi-major axis for bodies orbiting the Sun using T^2 = a^3 (years and AU).
होहमैन ट्रांसफ़र कैलकुलेटर
Compute the two delta-v burns and transfer time for a Hohmann transfer orbit between two circular orbits.
डेल्टा-V कैलकुलेटर
Compute the delta-v available from a rocket stage using the Tsiolkovsky equation: dv = v_e * ln(m0 / mf).
विशिष्ट कक्षीय ऊर्जा कैलकुलेटर
Find the specific mechanical energy of an orbit: epsilon = -G M / (2a).
हिल गोला कैलकुलेटर
Estimate the Hill sphere radius within which a body's gravity dominates: r_H = a * (m / (3M))^(1/3).
रोश सीमा कैलकुलेटर
Calculate the Roche limit, the minimum distance at which a self-gravitating satellite can orbit without tidal disruption.
सिनोडिक अवधि कैलकुलेटर
Calculate the synodic period between two orbiting bodies: the time between successive conjunctions as seen from one body.
नाक्षत्र से सिनोडिक कनवर्टर
Convert a planet's sidereal period to its synodic period relative to Earth.
उपग्रह गति कैलकुलेटर
Determine the speed and period of a satellite in circular orbit at a given altitude above Earth.
भूस्थिर कक्षा कैलकुलेटर
Compute the geostationary orbit altitude and speed for any planet given its mass and rotation period.
कक्षीय उत्केंद्रता कैलकुलेटर
Compute the eccentricity of an orbit from its periapsis and apoapsis distances: e = (r_a - r_p) / (r_a + r_p).
प्रकाश-वर्ष से किलोमीटर कनवर्टर
Convert astronomical distances between light-years and kilometres. One light-year is the distance light travels in one Julian year.
पारसेक से प्रकाश-वर्ष कनवर्टर
Convert distances between parsecs and light-years. One parsec is the distance at which 1 AU subtends 1 arcsecond of parallax.
लंबन दूरी कैलकुलेटर
Calculate the distance to a star from its parallax angle: d(pc) = 1/p(arcsec).
खगोलीय इकाई कनवर्टर
Convert between Astronomical Units (AU) and kilometres, miles, and light-minutes.
लाल विचलन वेग कैलकुलेटर
Estimate a galaxy's recession velocity from its cosmological redshift using the classical approximation v = z * c.
हबल दूरी कैलकुलेटर
Estimate the distance to a galaxy from its recession velocity using Hubble's law: d = v / H0.
लुकबैक समय कैलकुलेटर
Estimate the lookback time (how far back in time you are seeing) from distance in megaparsecs, using t = d / c.
कोणीय आकार कैलकुलेटर
Compute the angular size of an object from its physical diameter and distance: theta = 2 arctan(d / (2D)), approximated as theta = d / D (radians) for small angles.
दृश्य परिमाण कैलकुलेटर
Determine a star's apparent magnitude from its absolute magnitude and distance using the distance modulus: m = M + 5 log10(d/10).
निरपेक्ष परिमाण कैलकुलेटर
Find a star's absolute magnitude from its apparent magnitude and distance: M = m - 5 log10(d/10).
दूरी मॉड्यूलस कैलकुलेटर
Calculate the distance to a star from the difference between apparent and absolute magnitudes: d = 10^((m - M + 5) / 5).
प्रकाशमानता कैलकुलेटर
Calculate the luminosity of a star from its flux and distance using L = 4 pi d^2 F.
तारकीय फ्लक्स कैलकुलेटर
Calculate the observed flux from a star of known luminosity at a given distance: F = L / (4 pi d^2).
व्युत्क्रम वर्ग चमक कैलकुलेटर
Compare the brightness of an object at two different distances using the inverse square law: F2/F1 = (d1/d2)^2.
ब्रह्मांडीय दूरी सीढ़ी कैलकुलेटर
Enter a distance in parsecs and see which measurement methods are appropriate at that scale, plus conversions to multiple units.
तारकीय प्रकाशमानता कैलकुलेटर
Calculate a star's luminosity from its absolute magnitude: L/L_sun = 10^((M_sun - M_star) / 2.5).
हर्ट्ज़स्प्रंग-रसेल एस्टीमेटर
Estimate a main-sequence star's luminosity and radius from its effective temperature using empirical scaling relations.
मुख्य अनुक्रम जीवनकाल कैलकुलेटर
Estimate how long a star spends on the main sequence: t = t_sun * (M/M_sun) / (L/L_sun), approximated as t ≈ 10^10 * (M/M_sun)^(-2.5) years.
श्वार्ज़्सचाइल्ड त्रिज्या कैलकुलेटर
Calculate the Schwarzschild radius (event horizon) of a black hole: r_s = 2 G M / c^2.
चंद्रशेखर सीमा कैलकुलेटर
Compute the Chandrasekhar mass limit for a white dwarf with a given mean molecular weight per electron: M_Ch = 5.83 / mu_e^2 solar masses.
न्यूट्रॉन तारा घनत्व कैलकुलेटर
Estimate the average density of a neutron star from its mass and radius: rho = 3M / (4 pi r^3).
श्वेत वामन त्रिज्या कैलकुलेटर
Estimate the radius of a white dwarf using the mass-radius relation: R/R_sun ~ 0.0126 * (M/M_sun)^(-1/3) for non-relativistic degeneracy.
तारकीय तापमान कैलकुलेटर
Estimate a star's surface temperature from its B-V colour index using the Ballesteros formula: T = 4600 * (1/(0.92*(B-V)+1.7) + 1/(0.92*(B-V)+0.62)).
वीन शिखर तरंगदैर्ध्य कैलकुलेटर
Find the peak emission wavelength of a blackbody from its temperature using Wien's displacement law: lambda_max = b / T.
स्टीफ़न-बोल्ट्ज़मैन प्रकाशमानता कैलकुलेटर
Calculate a star's luminosity from its radius and surface temperature: L = 4 pi R^2 sigma T^4.
एडिंगटन प्रकाशमानता कैलकुलेटर
Compute the Eddington luminosity, the maximum luminosity a body can achieve when radiation pressure balances gravity: L_Edd = 4 pi G M c / kappa.
द्रव्यमान-प्रकाशमानता संबंध कैलकुलेटर
Estimate a main-sequence star's luminosity from its mass using the empirical relation L/L_sun ~ (M/M_sun)^3.5.
वर्णक्रमीय वर्ग एस्टीमेटर
Estimate which spectral class (O, B, A, F, G, K, M) a star belongs to based on its effective temperature.
तारे का रंग-तापमान कैलकुलेटर
Convert between a star's colour temperature in Kelvin and its peak emission wavelength, plus approximate visible colour description.
नाभिकीय संलयन ऊर्जा कैलकुलेटर
Calculate the energy released by converting a given mass of hydrogen to helium via stellar fusion (0.7% mass-energy conversion): E = 0.007 m c^2.
ग्रह गुरुत्वाकर्षण कैलकुलेटर
Calculate the surface gravity of a planet relative to Earth from its mass and radius ratios: g = g_Earth * (M/M_Earth) / (R/R_Earth)^2.
ग्रह वज़न कैलकुलेटर
Find what you would weigh on another planet by scaling your Earth weight by the surface gravity ratio.
सौर मध्याह्न कैलकुलेटर
Estimate the local solar noon time from your longitude and the standard meridian of your time zone.
दिन की अवधि कैलकुलेटर
Estimate the number of daylight hours from your latitude and the Sun's declination using the hour-angle formula.
चंद्र कला कैलकुलेटर
Estimate the Moon's illumination fraction and phase from the number of days since the last known new moon.
दूरबीन आवर्धन कैलकुलेटर
Calculate the magnification of a telescope from the focal lengths of the objective and eyepiece: M = f_obj / f_eye.
दूरबीन विभेदन कैलकुलेटर
Compute the angular resolution (Dawes limit) of a telescope from its aperture: theta = 116 / D (arcseconds, D in mm).
दूरबीन फ़ोकल अनुपात कैलकुलेटर
Calculate the focal ratio (f-number) of a telescope: f/# = focal_length / aperture.
दृश्य क्षेत्र कैलकुलेटर
Calculate the true field of view of a telescope and eyepiece combination: TFOV = AFOV / Magnification.
सीमांत परिमाण कैलकुलेटर
Estimate the faintest star visible through a telescope: m_lim = 2 + 5 log10(D) where D is aperture in mm.
दूरबीन प्रकाश संग्रहण कैलकुलेटर
Compare the light-gathering power of a telescope to the naked eye: LGP = (D / d_eye)^2.
दूरबीन एग्ज़िट प्यूपिल कैलकुलेटर
Calculate the exit pupil of binoculars or a telescope eyepiece: exit_pupil = aperture / magnification.
कैमरा एक्सपोज़र नियम कैलकुलेटर
Calculate the maximum untracked exposure time before stars trail using the NPF rule or simplified 500 rule: t = 500 / (focal_length).
क्षुद्रग्रह टकराव ऊर्जा कैलकुलेटर
Estimate the kinetic energy of an asteroid impact from its diameter, density, and velocity: KE = 0.5 * (pi/6) * d^3 * rho * v^2.
ड्रेक समीकरण कैलकुलेटर
Estimate the number of detectable civilisations in the Milky Way using the Drake equation: N = R* * fp * ne * fl * fi * fc * L.
ब्रह्मांडीय विस्तार दर कैलकुलेटर
Estimate the recession velocity of a distant galaxy from the Hubble-Lemaitre law v = H0 * d, where H0 is the Hubble constant.
श्याम ऊर्जा घनत्व कैलकुलेटर
Compute the dark-energy density of the universe from the cosmological constant and the speed of light using rho_Lambda = Lambda * c^2 / (8 * pi * G).
पदार्थ घनत्व पैरामीटर कैलकुलेटर
Calculate the matter density parameter Omega_m = rho_m / rho_crit, indicating what fraction of the critical density is made up of matter.
क्रांतिक घनत्व कैलकुलेटर
Compute the critical density of the universe rho_crit = 3 H0^2 / (8 pi G), the density needed for a flat geometry.
मंदन पैरामीटर कैलकुलेटर
Estimate the deceleration parameter q0 = Omega_m / 2 - Omega_Lambda, which indicates whether the expansion of the universe is accelerating or decelerating.
सह-चलित दूरी कैलकुलेटर
Approximate the comoving distance to a galaxy at low redshift using d = c * z / H0, the linearised Hubble relation.
उचित दूरी कैलकुलेटर
Convert comoving distance to the physical (proper) distance at a given epoch using d_proper = a(t) * d_comoving, where a is the scale factor.
ब्रह्मांडीय आयु कैलकुलेटर
Estimate the age of the universe as t ≈ 1 / H0 (the Hubble time), providing a rough upper bound for a matter-only universe.
बैरियन घनत्व कैलकुलेटर
Compute the baryon (ordinary matter) density parameter Omega_b from the baryon density and the critical density.
हबल समय कैलकुलेटर
Calculate the Hubble time t_H = 1/H0, the characteristic timescale of cosmic expansion, in seconds and gigayears.
ग्रह कक्षीय अवधि कैलकुलेटर
Find the orbital period of a planet using Kepler's third law in a simplified form: T = sqrt(a^3) years, where a is the semi-major axis in AU.
ग्रह सतह तापमान कैलकुलेटर
Estimate the effective surface temperature of a planet using Stefan-Boltzmann balance: T = ((L * (1 - A)) / (16 * pi * sigma * d^2))^0.25.
वायुमंडलीय स्केल ऊंचाई कैलकुलेटर
Calculate the atmospheric scale height H = k_B * T / (m * g), the altitude over which pressure drops by a factor of e.
ज्वारीय बल कैलकुलेटर
Compute the differential tidal acceleration across an object of size dr due to a mass M at distance d: a_tidal = 2 G M dr / d^3.
ग्रह ऐल्बीडो कैलकुलेटर
Determine a planet's bond albedo from the reflected and incident flux: A = F_reflected / F_incident.
ग्रह साम्यावस्था तापमान कैलकुलेटर
Compute the radiative equilibrium temperature of a planet from stellar properties and albedo: T_eq = T_star * sqrt(R_star / (2 * d)) * pow(1 - A, 0.25).
ग्रहीय चुंबकीय क्षेत्र शक्ति कैलकुलेटर
Estimate a planet's dipole magnetic field strength at the surface using the dipole approximation B = (mu0 / 4pi) * M_dipole / R^3.
ऊंचाई पर वायुमंडलीय दबाव कैलकुलेटर
Calculate the atmospheric pressure at a given altitude using the barometric formula P = P0 * exp(-h / H), where H is the scale height.
ग्रह घनत्व कैलकुलेटर
Calculate the mean bulk density of a planet from its mass and radius: rho = 3 M / (4 pi R^3).
ग्रह पलायन वेग कैलकुलेटर
Compute the escape velocity from a planet's surface using v_esc = sqrt(2 G M / R).
कैमरा सेंसर FOV कैलकुलेटर
Calculate the field of view of a camera sensor attached to a telescope: FOV = 2 * atan(sensor_size / (2 * focal_length)) converted to degrees.
पिक्सेल स्केल कैलकुलेटर
Determine the angular size each pixel subtends on the sky: pixel_scale = 206.265 * pixel_size / focal_length arcseconds per pixel.
छवि रिज़ॉल्यूशन कैलकुलेटर
Calculate the angular resolution of a telescope from its aperture using the Dawes limit: theta = 116 / D arcseconds, where D is in mm.
तारों के लिए एक्सपोज़र समय कैलकुलेटर
Calculate the maximum exposure time before stars trail using the NPF rule: t = (35 * N + 30 * p) / (f * cos(dec)), with declination correction.
स्टैकिंग सिग्नल-टू-नॉइज़ कैलकुलेटर
Estimate the signal-to-noise improvement from stacking multiple exposures: SNR_total = SNR_single * sqrt(n).
प्रकाश प्रदूषण प्रभाव कैलकुलेटर
Estimate how light pollution reduces contrast by computing the sky-brightness ratio: contrast_loss = sky_brightness / (sky_brightness + object_brightness).
फ़ोकल रिड्यूसर प्रभाव कैलकुलेटर
Calculate the effective focal length and f-ratio after adding a focal reducer: f_eff = f * reduction_factor, N_eff = N * reduction_factor.
बार्लो आवर्धन कैलकुलेटर
Calculate the effective focal length and f-ratio after adding a Barlow lens: f_eff = f * barlow_factor.
CCD क्वांटम दक्षता कैलकुलेटर
Calculate the number of photoelectrons generated by a CCD sensor: electrons = photon_flux * area * QE * exposure_time.
ट्रैकिंग त्रुटि सहनशीलता कैलकुलेटर
Determine the maximum acceptable periodic error of a mount: PE_max = pixel_scale * acceptable_drift_px, in arcseconds.
रॉकेट डेल्टा-V कैलकुलेटर
Calculate the total delta-v a rocket can achieve from the Tsiolkovsky equation: dv = ve * ln(m0 / mf).
त्सिओल्कोव्स्की समीकरण कैलकुलेटर
Compute the required mass ratio for a given delta-v and exhaust velocity: m0/mf = exp(dv / ve).
विशिष्ट आवेग कैलकुलेटर
Calculate the specific impulse of a rocket engine: Isp = ve / g0, the exhaust velocity normalised by standard gravity.
प्रणोद-भार अनुपात कैलकुलेटर
Calculate the thrust-to-weight ratio of a rocket: TWR = thrust / (mass * g), determining if it can lift off.
कक्षीय पैंतरा लागत कैलकुलेटर
Calculate the delta-v for a Hohmann transfer between two circular orbits: dv = sqrt(GM/r1) * (sqrt(2r2/(r1+r2)) - 1) + sqrt(GM/r2) * (1 - sqrt(2r1/(r1+r2))).
गुरुत्वीय सहायता गति कैलकुलेटर
Estimate the maximum speed change from a gravity assist: dv_max = 2 * v_planet * sin(theta/2), where theta is the bending angle.
पुनः प्रवेश तापन कैलकुलेटर
Estimate the stagnation-point heat flux during atmospheric reentry using q = k * sqrt(rho / r_nose) * v^3, the Sutton-Graves correlation.
सौर पाल त्वरण कैलकुलेटर
Calculate the acceleration of a solar sail from radiation pressure: a = 2 * S * A_sail / (c * m * d^2), where S is solar flux at 1 AU.
मिशन ईंधन द्रव्यमान कैलकुलेटर
Calculate the fuel mass required for a mission: m_fuel = m_dry * (exp(dv / ve) - 1).
अंतरतारकीय यात्रा समय कैलकुलेटर
Estimate the travel time to a star at constant velocity: t = d / v, where d is the distance in light-years.